Update ci.yml

Update documentation
Move nontype.hpp to detail
2026-01-19 16:12:15 +00:00 · 2026-01-16 02:16:52 +02:00 · 2025-11-18 14:33:45 +02:00 · 2025-11-18 14:33:45 +02:00 · 2025-11-18 12:06:25 +02:00 · 2025-11-03 18:54:47 +02:00
102 changed files with 12051 additions and 80 deletions
--- a/.drone.jsonnet
+++ b/.drone.jsonnet
@@ -0,0 +1,295 @@
+# Copyright 2022 Peter Dimov
+# Distributed under the Boost Software License, Version 1.0.
+# https://www.boost.org/LICENSE_1_0.txt
+
+local library = "compat";
+
+local triggers =
+{
+    branch: [ "master", "develop", "feature/*" ]
+};
+
+local ubsan = { UBSAN: '1', UBSAN_OPTIONS: 'print_stacktrace=1' };
+local asan = { ASAN: '1' };
+
+local linux_pipeline(name, image, environment, packages = "", sources = [], arch = "amd64") =
+{
+    name: name,
+    kind: "pipeline",
+    type: "docker",
+    trigger: triggers,
+    platform:
+    {
+        os: "linux",
+        arch: arch
+    },
+    steps:
+    [
+        {
+            name: "everything",
+            image: image,
+            environment: environment,
+            commands:
+            [
+                'set -e',
+                'uname -a',
+                'echo $DRONE_STAGE_MACHINE',
+            ] +
+            (if sources != [] then [ ('apt-add-repository "' + source + '"') for source in sources ] else []) +
+            (if packages != "" then [ 'apt-get update', 'apt-get -y install ' + packages ] else []) +
+            [
+                'export LIBRARY=' + library,
+                './.drone/drone.sh',
+            ]
+        }
+    ]
+};
+
+local macos_pipeline(name, environment, xcode_version = "12.2", osx_version = "catalina", arch = "amd64") =
+{
+    name: name,
+    kind: "pipeline",
+    type: "exec",
+    trigger: triggers,
+    platform: {
+        "os": "darwin",
+        "arch": arch
+    },
+    node: {
+        "os": osx_version
+    },
+    steps: [
+        {
+            name: "everything",
+            environment: environment + { "DEVELOPER_DIR": "/Applications/Xcode-" + xcode_version + ".app/Contents/Developer" },
+            commands:
+            [
+                'export LIBRARY=' + library,
+                './.drone/drone.sh',
+            ]
+        }
+    ]
+};
+
+local windows_pipeline(name, image, environment, arch = "amd64") =
+{
+    name: name,
+    kind: "pipeline",
+    type: "docker",
+    trigger: triggers,
+    platform:
+    {
+        os: "windows",
+        arch: arch
+    },
+    "steps":
+    [
+        {
+            name: "everything",
+            image: image,
+            environment: environment,
+            commands:
+            [
+                'cmd /C .drone\\\\drone.bat ' + library,
+            ]
+        }
+    ]
+};
+
+[
+    linux_pipeline(
+        "Linux 16.04 GCC 4.8 32/64",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-4.8', CXXSTD: '11', ADDRMD: '32,64' },
+        "g++-4.8-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 16.04 GCC 4.9 32/64",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-4.9', CXXSTD: '11', ADDRMD: '32,64' },
+        "g++-4.9-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 16.04 GCC 5* 32/64",
+        "cppalliance/droneubuntu1604:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '11,14', ADDRMD: '32,64' },
+    ),
+
+    linux_pipeline(
+        "Linux 18.04 GCC 7* 32/64",
+        "cppalliance/droneubuntu1804:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '11,14,17', ADDRMD: '32,64' },
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 GCC 9* ARM64 UBSAN",
+        "cppalliance/droneubuntu2004:multiarch",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '11,14,17,2a' } + ubsan,
+        arch="arm64",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 GCC 9* ARM64 ASAN",
+        "cppalliance/droneubuntu2004:multiarch",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '11,14,17,2a' } + asan,
+        arch="arm64",
+    ),
+
+    linux_pipeline(
+        "Linux 20.04 GCC 9* S390x UBSAN",
+        "cppalliance/droneubuntu2004:multiarch",
+        { TOOLSET: 'gcc', COMPILER: 'g++', CXXSTD: '11,14,17,2a' } + ubsan,
+        arch="s390x",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 GCC 12 32/64",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-12', CXXSTD: '11,14,17,20', ADDRMD: '32,64' },
+        "g++-12-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 GCC 13 32/64",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-13', CXXSTD: '11,14,17,20,2b', ADDRMD: '32,64' },
+        "g++-13-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 GCC 14 32/64 ASAN",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-14', CXXSTD: '11,14,17,20,2b', ADDRMD: '32,64' } + asan,
+        "g++-14-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 GCC 14 32/64 UBSAN",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-14', CXXSTD: '11,14,17,20,2b', ADDRMD: '32,64' } + ubsan,
+        "g++-14-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 25.10 GCC 15 32/64",
+        "cppalliance/droneubuntu2510:1",
+        { TOOLSET: 'gcc', COMPILER: 'g++-15', CXXSTD: '11,14,17,20,23,2c', ADDRMD: '32,64' },
+        "g++-15-multilib",
+    ),
+
+    linux_pipeline(
+        "Linux 22.04 Clang 15",
+        "cppalliance/droneubuntu2204:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-15', CXXSTD: '11,14,17,20,2b' },
+        "clang-15",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 Clang 16",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-16', CXXSTD: '11,14,17,20,2b' },
+        "clang-16",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 Clang 17",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-17', CXXSTD: '11,14,17,20,2b' },
+        "clang-17",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 Clang 18",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-18', CXXSTD: '11,14,17,20,2b' },
+        "clang-18",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 Clang 19",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-19', CXXSTD: '11,14,17,20,2b' },
+        "clang-19",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 Clang 20 UBSAN",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-20', CXXSTD: '11,14,17,20,23,2c' } + ubsan,
+        "clang-20",
+    ),
+
+    linux_pipeline(
+        "Linux 24.04 Clang 20 ASAN",
+        "cppalliance/droneubuntu2404:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-20', CXXSTD: '11,14,17,20,23,2c' } + asan,
+        "clang-20",
+    ),
+
+    linux_pipeline(
+        "Linux 25.10 Clang 21",
+        "cppalliance/droneubuntu2510:1",
+        { TOOLSET: 'clang', COMPILER: 'clang++-21', CXXSTD: '11,14,17,20,23,2c' },
+        "clang-21",
+    ),
+
+    macos_pipeline(
+        "MacOS 10.15 Xcode 12.2 UBSAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '11,14,1z' } + ubsan,
+    ),
+
+    macos_pipeline(
+        "MacOS 10.15 Xcode 12.2 ASAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '11,14,1z' } + asan,
+    ),
+
+    macos_pipeline(
+        "MacOS 12.4 Xcode 13.4.1 UBSAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '11,14,17,20,2b' } + ubsan,
+        xcode_version = "13.4.1", osx_version = "monterey", arch = "arm64",
+    ),
+
+    macos_pipeline(
+        "MacOS 12.4 Xcode 13.4.1 ASAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '11,14,17,20,2b' } + asan,
+        xcode_version = "13.4.1", osx_version = "monterey", arch = "arm64",
+    ),
+
+    macos_pipeline(
+        "MacOS 14 Xcode 16.2.0 UBSAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,17,20,2b' } + ubsan,
+        xcode_version = "16.2.0", osx_version = "sonoma", arch = "arm64",
+    ),
+
+    macos_pipeline(
+        "MacOS 14 Xcode 16.2.0 ASAN",
+        { TOOLSET: 'clang', COMPILER: 'clang++', CXXSTD: '03,11,14,17,20,2b' } + asan,
+        xcode_version = "16.2.0", osx_version = "sonoma", arch = "arm64",
+    ),
+
+    windows_pipeline(
+        "Windows VS2015 msvc-14.0",
+        "cppalliance/dronevs2015",
+        { TOOLSET: 'msvc-14.0', CXXSTD: '14,latest', B2_DONT_EMBED_MANIFEST: '1' },
+    ),
+
+    windows_pipeline(
+        "Windows VS2017 msvc-14.1",
+        "cppalliance/dronevs2017",
+        { TOOLSET: 'msvc-14.1', CXXSTD: '14,17,latest' },
+    ),
+
+    windows_pipeline(
+        "Windows VS2019 msvc-14.2",
+        "cppalliance/dronevs2019",
+        { TOOLSET: 'msvc-14.2', CXXSTD: '14,17,20,latest' },
+    ),
+
+    windows_pipeline(
+        "Windows VS2022 msvc-14.3",
+        "cppalliance/dronevs2022:1",
+        { TOOLSET: 'msvc-14.3', CXXSTD: '14,17,20,latest' },
+    ),
+]
--- a/.drone/drone.bat
+++ b/.drone/drone.bat
@@ -0,0 +1,25 @@
+@REM Copyright 2022 Peter Dimov
+@REM Distributed under the Boost Software License, Version 1.0.
+@REM https://www.boost.org/LICENSE_1_0.txt
+
+@ECHO ON
+
+set LIBRARY=%1
+set DRONE_BUILD_DIR=%CD%
+
+echo %DRONE_STAGE_MACHINE%
+
+set BOOST_BRANCH=develop
+if "%DRONE_BRANCH%" == "master" set BOOST_BRANCH=master
+cd ..
+git clone -b %BOOST_BRANCH% --depth 1 https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/boostdep
+xcopy /s /e /q %DRONE_BUILD_DIR% libs\%LIBRARY%\
+python tools/boostdep/depinst/depinst.py %LIBRARY%
+cmd /c bootstrap
+b2 -d0 headers
+
+if not "%CXXSTD%" == "" set CXXSTD=cxxstd=%CXXSTD%
+if not "%ADDRMD%" == "" set ADDRMD=address-model=%ADDRMD%
+b2 -j3 libs/%LIBRARY%/test toolset=%TOOLSET% %CXXSTD% %ADDRMD% variant=debug,release embed-manifest-via=linker
--- a/.drone/drone.sh
+++ b/.drone/drone.sh
@@ -0,0 +1,31 @@
+#!/bin/bash
+
+# Copyright 2022 Peter Dimov
+# Distributed under the Boost Software License, Version 1.0.
+# https://www.boost.org/LICENSE_1_0.txt
+
+set -ex
+export PATH=~/.local/bin:/usr/local/bin:$PATH
+
+uname -a
+echo $DRONE_STAGE_MACHINE
+command -v lscpu && lscpu
+
+DRONE_BUILD_DIR=$(pwd)
+
+BOOST_BRANCH=develop
+if [ "$DRONE_BRANCH" = "master" ]; then BOOST_BRANCH=master; fi
+
+cd ..
+git clone -b $BOOST_BRANCH --depth 1 https://github.com/boostorg/boost.git boost-root
+cd boost-root
+git submodule update --init tools/boostdep
+cp -r $DRONE_BUILD_DIR/* libs/$LIBRARY
+python tools/boostdep/depinst/depinst.py $LIBRARY
+CXXFLAGS= ./bootstrap.sh
+./b2 -d0 headers
+
+echo "using $TOOLSET : : $COMPILER ;" > ~/user-config.jam
+./b2 -j2 libs/$LIBRARY/test toolset=$TOOLSET cxxstd=$CXXSTD variant=debug,release \
+  ${ADDRMD:+address-model=$ADDRMD} ${CXXFLAGS:+cxxflags=$CXXFLAGS} ${LINKFLAGS:+linkflags=$LINKFLAGS} \
+  ${UBSAN:+undefined-sanitizer=norecover debug-symbols=on} ${ASAN:+address-sanitizer=norecover debug-symbols=on}
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,146 +19,216 @@ jobs:
        include:
          - toolset: gcc-4.8
            cxxstd: "03,11"
-            os: ubuntu-latest
            container: ubuntu:18.04
+            os: ubuntu-latest
            install: g++-4.8
+          - toolset: gcc-4.9
+            cxxstd: "03,11"
+            container: ubuntu:16.04
+            os: ubuntu-latest
+            install: g++-4.9
          - toolset: gcc-5
            cxxstd: "03,11,14,1z"
-            os: ubuntu-latest
            container: ubuntu:18.04
+            os: ubuntu-latest
            install: g++-5
          - toolset: gcc-6
            cxxstd: "03,11,14,1z"
-            os: ubuntu-latest
            container: ubuntu:18.04
+            os: ubuntu-latest
            install: g++-6
          - toolset: gcc-7
            cxxstd: "03,11,14,17"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: g++-7
          - toolset: gcc-8
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: g++-8
          - toolset: gcc-9
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
          - toolset: gcc-10
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: g++-10
          - toolset: gcc-11
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
-            install: g++-11
+            os: ubuntu-22.04
          - toolset: gcc-12
            cxxstd: "03,11,14,17,20,2b"
            os: ubuntu-22.04
            install: g++-12
          - toolset: gcc-13
            cxxstd: "03,11,14,17,20,2b"
+            container: ubuntu:24.04
            os: ubuntu-latest
-            container: ubuntu:23.04
            install: g++-13
+          - toolset: gcc-14
+            cxxstd: "03,11,14,17,20,2b"
+            container: ubuntu:24.04
+            os: ubuntu-latest
+            install: g++-14
+          - toolset: gcc-15
+            cxxstd: "03,11,14,17,20,23,2c"
+            container: ubuntu:25.04
+            os: ubuntu-latest
+            install: g++-15
          - toolset: clang
            compiler: clang++-3.9
            cxxstd: "03,11,14"
-            os: ubuntu-latest
            container: ubuntu:18.04
+            os: ubuntu-latest
            install: clang-3.9
          - toolset: clang
            compiler: clang++-4.0
            cxxstd: "03,11,14"
-            os: ubuntu-latest
            container: ubuntu:18.04
+            os: ubuntu-latest
            install: clang-4.0
          - toolset: clang
            compiler: clang++-5.0
            cxxstd: "03,11,14,1z"
-            os: ubuntu-latest
            container: ubuntu:18.04
+            os: ubuntu-latest
            install: clang-5.0
          - toolset: clang
            compiler: clang++-6.0
            cxxstd: "03,11,14,17"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-6.0
          - toolset: clang
            compiler: clang++-7
            cxxstd: "03,11,14,17"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-7
          - toolset: clang
            compiler: clang++-8
            cxxstd: "03,11,14,17"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-8
          - toolset: clang
            compiler: clang++-9
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-9
          - toolset: clang
            compiler: clang++-10
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-10
          - toolset: clang
            compiler: clang++-11
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-11
          - toolset: clang
            compiler: clang++-12
            cxxstd: "03,11,14,17,2a"
-            os: ubuntu-20.04
+            container: ubuntu:20.04
+            os: ubuntu-latest
            install: clang-12
          - toolset: clang
            compiler: clang++-13
            cxxstd: "03,11,14,17,20,2b"
-            os: ubuntu-22.04
+            container: ubuntu:22.04
+            os: ubuntu-latest
            install: clang-13
          - toolset: clang
            compiler: clang++-14
            cxxstd: "03,11,14,17,20,2b"
-            os: ubuntu-22.04
+            container: ubuntu:22.04
+            os: ubuntu-latest
            install: clang-14
          - toolset: clang
            compiler: clang++-15
            cxxstd: "03,11,14,17,20,2b"
-            os: ubuntu-22.04
+            container: ubuntu:22.04
+            os: ubuntu-latest
            install: clang-15
          - toolset: clang
            compiler: clang++-16
            cxxstd: "03,11,14,17,20,2b"
+            container: ubuntu:24.04
            os: ubuntu-latest
-            container: ubuntu:23.04
            install: clang-16
          - toolset: clang
-            cxxstd: "03,11,14,17,2a"
-            os: macos-11
+            compiler: clang++-17
+            cxxstd: "03,11,14,17,20,2b"
+            container: ubuntu:24.04
+            os: ubuntu-latest
+            install: clang-17
+          - toolset: clang
+            compiler: clang++-18
+            cxxstd: "03,11,14,17,20,2b"
+            container: ubuntu:24.04
+            os: ubuntu-latest
+            install: clang-18
+          - toolset: clang
+            compiler: clang++-19
+            cxxstd: "03,11,14,17,20,2b"
+            container: ubuntu:24.04
+            os: ubuntu-latest
+            install: clang-19
+          - toolset: clang
+            compiler: clang++-20
+            cxxstd: "03,11,14,17,20,23,2c"
+            container: ubuntu:24.04
+            os: ubuntu-latest
+            install: clang-20
+          - toolset: clang
+            compiler: clang++-21
+            cxxstd: "03,11,14,17,20,23,2c"
+            container: ubuntu:25.10
+            os: ubuntu-latest
+            install: clang-21
          - toolset: clang
            cxxstd: "03,11,14,17,20,2b"
-            os: macos-12
+            os: macos-14
          - toolset: clang
-            cxxstd: "03,11,14,17,20,2b"
-            os: macos-13
+            cxxstd: "03,11,14,17,20,23,2c"
+            os: macos-15
+          - toolset: clang
+            cxxstd: "03,11,14,17,20,23,2c"
+            os: macos-26

    runs-on: ${{matrix.os}}
-    container: ${{matrix.container}}
+
+    container:
+      image: ${{matrix.container}}
+      volumes:
+        - /node20217:/node20217:rw,rshared
+        - ${{ startsWith(matrix.container, 'ubuntu:1') && '/node20217:/__e/node20:ro,rshared' || ' ' }}

    defaults:
      run:
        shell: bash

    steps:
-      - uses: actions/checkout@v3
-
      - name: Setup container environment
        if: matrix.container
        run: |
          apt-get update
-          apt-get -y install sudo python3 git g++
+          apt-get -y install sudo python3 git g++ curl xz-utils
+
+      - name: Install nodejs20glibc2.17
+        if: ${{ startsWith( matrix.container, 'ubuntu:1' ) }}
+        run: |
+          curl -LO https://archives.boost.io/misc/node/node-v20.9.0-linux-x64-glibc-217.tar.xz
+          tar -xf node-v20.9.0-linux-x64-glibc-217.tar.xz --strip-components 1 -C /node20217
+          ldd /__e/node20/bin/node
+
+      - uses: actions/checkout@v4

      - name: Install packages
        if: matrix.install
@@ -185,7 +255,7 @@ jobs:
          mkdir -p libs/$LIBRARY
          cp -r $GITHUB_WORKSPACE/* libs/$LIBRARY
          git submodule update --init tools/boostdep
-          python3 tools/boostdep/depinst/depinst.py --git_args "--jobs 3" $LIBRARY
+          python3 tools/boostdep/depinst/depinst.py $LIBRARY
          ./bootstrap.sh
          ./b2 -d0 headers

@@ -204,14 +274,6 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - toolset: msvc-14.0
-            cxxstd: "14,latest"
-            addrmd: 32,64
-            os: windows-2019
-          - toolset: msvc-14.2
-            cxxstd: "14,17,20,latest"
-            addrmd: 32,64
-            os: windows-2019
          - toolset: msvc-14.3
            cxxstd: "14,17,20,latest"
            addrmd: 32,64
@@ -223,12 +285,12 @@ jobs:
          - toolset: gcc
            cxxstd: "03,11,14,17,2a"
            addrmd: 64
-            os: windows-2019
+            os: windows-2022

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Setup Boost
        shell: cmd
@@ -263,16 +325,16 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - os: ubuntu-20.04
          - os: ubuntu-22.04
-          - os: macos-11
-          - os: macos-12
-          - os: macos-13
+          - os: ubuntu-24.04
+          - os: macos-14
+          - os: macos-15
+          - os: macos-26

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Install packages
        if: matrix.install
@@ -312,16 +374,16 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - os: ubuntu-20.04
          - os: ubuntu-22.04
-          - os: macos-11
-          - os: macos-12
-          - os: macos-13
+          - os: ubuntu-24.04
+          - os: macos-14
+          - os: macos-15
+          - os: macos-26

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Install packages
        if: matrix.install
@@ -371,16 +433,16 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - os: ubuntu-20.04
          - os: ubuntu-22.04
-          - os: macos-11
-          - os: macos-12
-          - os: macos-13
+          - os: ubuntu-24.04
+          - os: macos-14
+          - os: macos-15
+          - os: macos-26

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Install packages
        if: matrix.install
@@ -428,13 +490,12 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - os: windows-2019
-          - os: windows-2022
+          - os: windows-latest

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Setup Boost
        shell: cmd
@@ -477,13 +538,12 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - os: windows-2019
-          - os: windows-2022
+          - os: windows-latest

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Setup Boost
        shell: cmd
@@ -544,13 +604,12 @@ jobs:
      fail-fast: false
      matrix:
        include:
-          - os: windows-2019
-          - os: windows-2022
+          - os: windows-latest

    runs-on: ${{matrix.os}}

    steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4

      - name: Setup Boost
        shell: cmd
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1,5 @@
+/__build__
+/toolchain.cmake
+/compile_commands.json
+/.cache
+/.vscode
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,6 +15,8 @@ target_include_directories(boost_compat INTERFACE include)
 target_link_libraries(boost_compat
  INTERFACE
    Boost::assert
+    Boost::config
+    Boost::throw_exception
 )

 target_compile_features(boost_compat INTERFACE cxx_std_11)
--- a/build.jam
+++ b/build.jam
@@ -0,0 +1,22 @@
+# Copyright 2024 René Ferdinand Rivera Morell
+# Copyright 2024 Peter Dimov
+# Distributed under the Boost Software License, Version 1.0.
+# https://www.boost.org/LICENSE_1_0.txt
+
+require-b2 5.2 ;
+
+constant boost_dependencies :
+    /boost/assert//boost_assert
+    /boost/config//boost_config
+    /boost/throw_exception//boost_throw_exception
+    ;
+
+project /boost/compat ;
+
+explicit
+    [ alias boost_compat : : : : <include>include <library>$(boost_dependencies) ]
+    [ alias all : boost_compat test ]
+    ;
+
+call-if : boost-library compat
+    ;
--- a/doc/compat.adoc
+++ b/doc/compat.adoc
@@ -17,8 +17,7 @@ https://www.boost.org/LICENSE_1_0.txt

 include::compat/overview.adoc[]
 include::compat/changelog.adoc[]
-include::compat/latch.adoc[]
-include::compat/shared_lock.adoc[]
+include::compat/reference.adoc[]
 include::compat/copyright.adoc[]

 :leveloffset: -1
--- a/doc/compat/bind_back.adoc
+++ b/doc/compat/bind_back.adoc
@@ -0,0 +1,58 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#bind_back]
+# <boost/compat/bind_back.hpp>
+:idprefix: ref_bind_back_
+
+## Description
+
+The header `<boost/compat/bind_back.hpp>` implements the {cpp}20 function
+`std::bind_back`.
+
+`bind_back` is a limited variant of `std::bind`. It only supports binding
+the last several parameters of a function object to specific argument values.
+
+## Example
+
+```
+struct X
+{
+    void f(int a, int b) const noexcept;
+};
+
+int main()
+{
+    auto fn = boost::compat::bind_back(&X::f, 1, 2);
+
+    X x;
+    fn(x); // calls x.f(1, 2)
+}
+```
+
+## Synopsis
+
+```
+namespace boost
+{
+namespace compat
+{
+
+template<class F, class... A> auto bind_back(F&& f, A&&... a);
+
+} // namespace compat
+} // namespace boost
+```
+
+## bind_back
+
+```
+template<class F, class... A> auto bind_back( F&& f, A&&... a );
+```
+
+[horizontal]
+Returns:;; A function object `fn` such that `fn(b...)` is equivalent to
+  `invoke(f, b..., a...)`.
--- a/doc/compat/bind_front.adoc
+++ b/doc/compat/bind_front.adoc
@@ -0,0 +1,58 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#bind_front]
+# <boost/compat/bind_front.hpp>
+:idprefix: ref_bind_front_
+
+## Description
+
+The header `<boost/compat/bind_front.hpp>` implements the {cpp}20 function
+`std::bind_front`.
+
+`bind_front` is a limited variant of `std::bind`. It only supports binding
+the first several parameters of a function object to specific argument values.
+
+## Example
+
+```
+struct X
+{
+    void f(int a, int b) const noexcept;
+};
+
+int main()
+{
+    X x;
+    auto fn = boost::compat::bind_front(&X::f, &x);
+
+    fn(1, 2); // calls x.f(1, 2)
+}
+```
+
+## Synopsis
+
+```
+namespace boost
+{
+namespace compat
+{
+
+template<class F, class... A> auto bind_front(F&& f, A&&... a);
+
+} // namespace compat
+} // namespace boost
+```
+
+## bind_front
+
+```
+template<class F, class... A> auto bind_front(F&& f, A&&... a);
+```
+
+[horizontal]
+Returns:;; A function object `fn` such that `fn(b...)` is equivalent to
+  `invoke(f, a..., b...)`.
--- a/doc/compat/changelog.adoc
+++ b/doc/compat/changelog.adoc
@@ -8,6 +8,23 @@ https://www.boost.org/LICENSE_1_0.txt
 # Revision History
 :idprefix: changelog_

+## Changes in 1.90.0
+
+* Added `to_underlying.hpp` (contributed by Braden Ganetsky.)
+
+## Changes in 1.89.0
+
+* Added `move_only_function.hpp`.
+
+## Changes in 1.87.0
+
+* Added `to_array.hpp` (contributed by Ruben Perez Hidalgo.)
+
+## Changes in 1.86.0
+
+* Added `bind_front.hpp`, `bind_back.hpp`, `invoke.hpp`, `mem_fn.hpp`, `integer_sequence.hpp` and `type_traits.hpp`.
+* Added `function_ref.hpp`.
+
 ## Changes in 1.83.0

 * Added `latch.hpp`, an implementation of `std::latch` (contributed by Christian Mazakas.)
--- a/doc/compat/copyright.adoc
+++ b/doc/compat/copyright.adoc
@@ -8,6 +8,6 @@ https://www.boost.org/LICENSE_1_0.txt
 # Copyright and License
 :idprefix:

-This documentation is copyright 2023 Peter Dimov and contributors and is
-distributed under the
+This documentation is copyright 2023, 2024 Peter Dimov and
+contributors and is distributed under the
 http://www.boost.org/LICENSE_1_0.txt[Boost Software License, Version 1.0].
--- a/doc/compat/function_ref.adoc
+++ b/doc/compat/function_ref.adoc
@@ -0,0 +1,205 @@
+////
+Copyright 2024 Christian Mazakas
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#function_ref]
+# <boost/compat/function_ref.hpp>
+:idprefix: ref_function_ref_
+
+## Description
+
+The header `<boost/compat/function_ref.hpp>` implements the {cpp}26 class
+`std::function_ref`.
+
+`function_ref` is a lightweight polymorphic function wrapper that only stores a pointer to the supplied https://en.cppreference.com/w/cpp/named_req/Callable[Callable] object and a pointer to an unspecified function, meaning it does not participate in ownership of the Callable and does not allocate. All specializations of `function_ref` satisfy https://en.cppreference.com/w/cpp/named_req/TriviallyCopyable[TriviallyCopyable].
+
+`function_ref` supports every combination of `const` and `noexcept` and is useful for writing higher-order functions as
+it can avoid a template parameter or an allocation (as `std::function` is known for).
+
+Since `nontype_t` requires {cpp}17 as it has a template parameter of type `auto`, the constructors taking `nontype_t<f>` are only available under {cpp}17 or later.
+
+## Example
+
+```cpp
+int add(int x, int y) noexcept { return x * 10 + y; }
+
+auto add2 = [](int x, int y) { return x * 100 + y; };
+
+std::vector<boost::compat::function_ref<int(int, int)>> fns;
+fns.push_back({add});
+fns.push_back({add2});
+
+for (auto fn : fns) {
+  std::cout << fn(1, 2) << std::endl;
+}
+```
+
+## Synopsis
+
+```cpp
+namespace boost
+{
+namespace compat
+{
+
+template <class... S>
+struct function_ref;
+
+// cv is either `const` or empty
+// noex is either `true` or `false`
+template<class R, class... ArgTypes>
+class function_ref<R(ArgTypes...) cv noexcept(noex)>
+{
+public:
+
+    template<class F> function_ref(F*) noexcept;
+    template<class F> function_ref(F&&) noexcept;
+
+    template<auto f> function_ref(nontype_t<f>) noexcept;
+    template<auto f, class U> function_ref(nontype_t<f>, U&&) noexcept;
+    template<auto f, class T> function_ref(nontype_t<f>, cv T*) noexcept;
+
+    function_ref(const function_ref&) noexcept = default;
+    function_ref& operator=(const function_ref&) noexcept = default;
+    template<class T> function_ref& operator=(T) = delete;
+
+    R operator()(ArgTypes...) const noexcept(noex);
+};
+
+} // namespace compat
+} // namespace boost
+```
+
+## Constructors
+
+### Function Pointer Constructor
+
+```cpp
+template<class F> function_ref(F* fn) noexcept;
+```
+
+[horizontal]
+Preconditions:: `fn` != `nullptr`.
+Effects::
+Constructs a `function_ref` which uses the supplied function pointer as its Callable. +
+
+Calling the `function_ref` is expression-equivalent to `invoke_r<R>(f, call-args...)`.
+
+
+### Object Constructor
+
+```cpp
+template<class F> function_ref(F&& fn) noexcept;
+```
+
+[horizontal]
+Effects:;; Constructs a `function_ref` that stores the address of the supplied Callable object `fn`. This overload only
+participates in resolution when `fn` is not a pointer-to-member or pointer-to-member-function. +
+
+Calling the `function_ref` is expression-equivalent to `invoke_r<R>(static_cast<cv T&>(f), call-args...)`.
+
+### Pointer to Member Function Constructor
+
+```cpp
+template<auto f> function_ref(nontype_t<f>) noexcept;
+```
+
+[horizontal]
+Effects:;; Constructs a `function_ref` using the supplied pointer to member function. This overload only participates
+in resolution when `f` is a pointer to member or pointer to member function. +
+
+Calling the `function_ref` is expression-equivalent to `invoke_r<R>(f, call-args)`.
+Example:;;
+
+--
+```cpp
+struct point { int x = 1, y = 2; };
+
+point p;
+compat::function_ref<int(point const&)> f(compat::nontype<&point::x>);
+
+BOOST_TEST_EQ(f(p), 1);
+```
+--
+
+### Bound Object Constructor
+
+```cpp
+template<auto f, class U> function_ref(nontype_t<f>, U&&) noexcept;
+```
+
+[horizontal]
+Effects:;; Constructs a `function_ref` using the supplied pointer to member or pointer to member function and a reference
+to an object to bind it to. +
+
+This overload only participates in resolution if `is_rvalue_reference_v<U&&>` is false.
+Example:;;
+
+--
+```cpp
+struct point { int x = 1, y = 2; };
+
+point p;
+compat::function_ref<int()> f(compat::nontype<&point::x>, p);
+
+BOOST_TEST_EQ(f(), 1);
+```
+--
+
+### Bound Pointer Constructor
+
+```cpp
+template<auto f, class T> function_ref(nontype_t<f>, cv T*) noexcept;
+```
+
+[horizontal]
+Effects:;; Constructs a `function_ref` using the supplied pointer to member or pointer to member function and a pointer
+to an object.
+Example:;;
+
+--
+```cpp
+struct point { int x = 1, y = 2; };
+
+point p;
+compat::function_ref<int()> f(compat::nontype<&point::x>, &p);
+
+BOOST_TEST_EQ(f(), 1);
+```
+--
+
+### Copy Constructor
+
+```cpp
+function_ref(const function_ref&) noexcept = default;
+```
+
+[horizontal]
+Effects:;; `function_ref` is a TriviallyCopyable type.
+
+## Member Functions
+
+### call operator
+
+```cpp
+R operator()(ArgTypes...) const noexcept(noex);
+```
+
+[horizontal]
+Effects:;; Invokes the underlying Callable object by forwarding the supplied arguments.
+
+## Assignment
+
+### Copy Assignment
+
+```cpp
+function_ref& operator=(const function_ref&) noexcept = default;
+template<class T> function_ref& operator=(T) = delete;
+```
+
+[horizontal]
+Effects:;; `operator=(T)` participates in overload resolution if:
+* `T` is not the same as `function_ref`
+* `is_pointer_v<T>` is `false`.
--- a/doc/compat/integer_sequence.adoc
+++ b/doc/compat/integer_sequence.adoc
@@ -0,0 +1,69 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#integer_sequence]
+# <boost/compat/integer_sequence.hpp>
+:idprefix: ref_integer_sequence_
+
+## Description
+
+The header `<boost/compat/integer_sequence.hpp>` implements the {cpp}14 utilities
+`std::integer_sequence`, `std::index_sequence`, `std::make_integer_sequence`,
+`std::make_index_sequence`, and `std::index_sequence_for`.
+
+## Synopsis
+
+```
+namespace boost
+{
+namespace compat
+{
+
+template<class T, T... I> struct integer_sequence;
+
+template<class T, T N> using make_integer_sequence = /*...*/;
+
+template<std::size_t... I> using index_sequence = /*...*/;
+
+template<std::size_t N> using make_index_sequence = /*...*/;
+
+template<class... T> using index_sequence_for = /*...*/;
+
+} // namespace compat
+} // namespace boost
+```
+
+## integer_sequence
+
+```
+template<class T, T... I> struct integer_sequence {};
+```
+
+## make_integer_sequence
+
+```
+template<class T, T N> using make_integer_sequence = /*...*/;
+```
+
+`make_integer_sequence<T, N>` is an alias for `integer_sequence<T, 0, 1, 2, ..., N-1>`.
+
+## index_sequence
+
+```
+template<std::size_t... I> using index_sequence = integer_sequence<std::size_t, I...>;
+```
+
+## make_index_sequence
+
+```
+template<std::size_t N> using make_index_sequence = make_integer_sequence<std::size_t, N>;
+```
+
+## index_sequence_for
+
+```
+template<class... T> using index_sequence_for = make_integer_sequence<std::size_t, sizeof...(T)>;
+```
--- a/doc/compat/invoke.adoc
+++ b/doc/compat/invoke.adoc
@@ -0,0 +1,130 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#invoke]
+# <boost/compat/invoke.hpp>
+:idprefix: ref_invoke_
+
+## Description
+
+The header `<boost/compat/invoke.hpp>` implements the {cpp}17 function
+`std::invoke`, the {cpp}23 function `std::invoke_r`, and the associated
+utilities `invoke_result_t`, `is_invocable`, `is_invocable_r`,
+`is_nothrow_invocable`, and `is_nothrow_invocable_r`.
+
+`invoke(f, a...)` generally returns `f(a...)`, but when `f` is a pointer to
+member, it invokes it as if by returning `mem_fn(f)(a...)`. This allows
+functions, function objects, and pointers to members to be treated uniformly
+by components such as `bind_front`.
+
+`invoke_r<R>(f, a...)` returns `invoke(f, a...)`, converted to `R`.
+
+## Example
+
+```
+struct X
+{
+    void f(int a, int b) const noexcept;
+};
+
+int main()
+{
+    X x;
+    boost::compat::invoke(&X::f, x, 1, 2); // calls x.f(1, 2)
+}
+```
+
+## Synopsis
+
+```
+namespace boost
+{
+namespace compat
+{
+
+template<class F, class... A> auto invoke(F&& f, A&&... a);
+
+template<class F, class... A> using invoke_result_t = /*...*/;
+
+template<class F, class... A> struct is_invocable;
+
+template<class F, class... A> struct is_nothrow_invocable;
+
+template<class R, class F, class... A> R invoke_r(F&& f, A&&... a);
+
+template<class R, class F, class... A> struct is_invocable_r;
+
+template<class R, class F, class... A> struct is_nothrow_invocable_r;
+
+} // namespace compat
+} // namespace boost
+```
+
+## invoke
+
+```
+template<class F, class... A> auto invoke(F&& f, A&&... a) noexcept(/*...*/) -> /*...*/;
+```
+
+[horizontal]
+Returns:;;
+  * `std::forward<F>(f)(std::forward<A>(a)...)`, when `f` is not a pointer to member;
+  * `mem_fn(f)(std::forward<A>(a)...)`, otherwise.
+Constraints:;; the return expression must be valid.
+Remarks:;; The return type is `decltype(r)`, and the `noexcept` clause is `noexcept(noexcept(r))`, where `r` is the return expression.
+
+## invoke_result_t
+
+```
+template<class F, class... A> using invoke_result_t =
+  decltype( invoke(std::declval<F>(), std::declval<A>()...) );
+```
+
+## is_invocable
+
+```
+template<class F, class... A> struct is_invocable: public /*...*/;
+```
+
+The base class of `is_invocable<F, A...>` is `std::true_type` when `invoke(std::declval<F>(), std::declval<A>()...)` is a valid expression, `std::false_type` otherwise.
+
+## is_nothrow_invocable
+
+```
+template<class F, class... A> struct is_nothrow_invocable: public /*...*/;
+```
+
+The base class of `is_nothrow_invocable<F, A...>` is `std::false_type` when `is_invocable<F, A...>::value` is `false`, `std::integral_constant<bool, noexcept(invoke(std::declval<F>(), std::declval<A>()...))>` otherwise.
+
+## invoke_r
+
+```
+template<class R, class F, class... A> R invoke_r(F&& f, A&&... a) noexcept(/*...*/);
+```
+
+[horizontal]
+Returns:;;
+  * `static_cast<R>(invoke(std::forward<F>(f), std::forward<A>(a)...))`, when `R` is (possibly cv-qualified) `void`;
+  * `invoke(std::forward<F>(f), std::forward<A>(a)...)`, implicitly converted to `R`, otherwise.
+Constraints:;; `is_invocable<F, A...>::value` must be `true` and, if `R` is not cv `void`, `std::is_convertible<invoke_result_t<F, A...>, R>::value` must be `true`.
+Remarks:;; The `noexcept` clause is `noexcept(noexcept(static_cast<R>(invoke(std::forward<F>(f), std::forward<A>(a)...))))`.
+
+## is_invocable_r
+
+```
+template<class R, class F, class... A> struct is_invocable: public /*...*/;
+```
+
+The base class of `is_invocable_r<R, F, A...>` is `std::true_type` when `invoke_r<R>(std::declval<F>(), std::declval<A>()...)` is a valid expression, `std::false_type` otherwise.
+
+## is_nothrow_invocable_r
+
+```
+template<class R, class F, class... A> struct is_nothrow_invocable: public /*...*/;
+```
+
+The base class of `is_nothrow_invocable<R, F, A...>` is `std::false_type` when `is_invocable_r<R, F, A...>::value` is `false`, `std::integral_constant<bool, noexcept(invoke_r<R>(std::declval<F>(), std::declval<A>()...))>` otherwise.
+
--- a/doc/compat/latch.adoc
+++ b/doc/compat/latch.adoc
@@ -6,7 +6,7 @@ https://www.boost.org/LICENSE_1_0.txt

 [#latch]
 # <boost/compat/latch.hpp>
-:idprefix: latch_
+:idprefix: ref_latch_

 ## Description

--- a/doc/compat/mem_fn.adoc
+++ b/doc/compat/mem_fn.adoc
@@ -0,0 +1,67 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#mem_fn]
+# <boost/compat/mem_fn.hpp>
+:idprefix: ref_mem_fn_
+
+## Description
+
+The header `<boost/compat/mem_fn.hpp>` implements the {cpp}11 function
+`std::mem_fn`.
+
+`mem_fn(pm)`, where `pm` is a pointer to member, returns a function object
+that can be used to invoke the member function, or obtain a reference to the
+data member, using a function call syntax.
+
+Even though `std::mem_fn` is {cpp}11, later standards place stricter
+requirements on the returned function object (it needs to be SFINAE friendly
+and propagate `noexcept` correctly.) `boost::compat::mem_fn` implements
+these stricter requirements.
+
+## Example
+
+```
+struct X
+{
+    void f(int a, int b) const noexcept;
+};
+
+int main()
+{
+    auto fn = boost::compat::mem_fn(&X::f);
+
+    X x;
+    fn(x, 1, 2); // calls x.f(1, 2)
+}
+```
+
+## Synopsis
+
+```
+namespace boost
+{
+namespace compat
+{
+
+template<class M, class T> auto mem_fn(M T::* pm) noexcept;
+
+} // namespace compat
+} // namespace boost
+```
+
+## mem_fn
+
+```
+template<class M, class T> auto mem_fn(M T::* pm) noexcept;
+```
+
+[horizontal]
+Returns:;; A function object `fn` such that:
+  * `fn(x, a...)` is equivalent to `(x.*pm)(a...)`, when `M` is a function type and the type of `X` is `T` or derived from `T`;
+  * `fn(x, a...)` is equivalent to `((*x).*pm)(a...)`, when `M` is a function type and the type of `X` is not `T` or derived from `T`;
+  * `fn(x)` is equivalent to `x.*pm`, when `M` is an object type and the type of `X` is `T` or derived from `T`;
+  * `fn(x)` is equivalent to `(*x).*pm`, when `M` is an object type and the type of `X` is not `T` or derived from `T`.
--- a/doc/compat/move_only_function.adoc
+++ b/doc/compat/move_only_function.adoc
@@ -0,0 +1,252 @@
+////
+Copyright 2025 Christian Mazakas
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#move_only_function]
+# <boost/compat/move_only_function.hpp>
+:idprefix: ref_move_only_function_
+
+## Description
+
+The header `<boost/compat/move_only_function.hpp>` implements the {cpp}23 class https://en.cppreference.com/w/cpp/utility/functional/move_only_function.html[std::move_only_function].
+
+`move_only_function` is a polymorphic wrapper that stores and manages a https://en.cppreference.com/w/cpp/named_req/Callable[Callable], only requiring that the type supports move construction and move assignment.
+This is in contrast to the commonly used `std::function` which requires copyability of the underlying managed object.
+
+`move_only_function` supports every combination of `const`, `noexcept` and reference qualification (none, `&`, `&&`).
+
+## Example
+
+```cpp
+struct moveonly
+{
+    std::unique_ptr<int> p_ = std::make_unique<int>( 1234 );
+    auto operator()( int x ) noexcept { return *p_ + x; }
+};
+
+boost::compat::move_only_function<int( int ) noexcept> f( moveonly{} );
+std::cout << f( 4321 ) << std::endl;
+```
+
+## Synopsis
+
+```cpp
+namespace boost {
+namespace compat {
+
+template<class... S>
+class move_only_function;
+
+template< class T >
+struct in_place_type_t { explicit in_place_type_t() = default; };
+
+template<class R, class ...Args>
+class move_only_function<R( Args... ) /* cv */ /* ref */ noexcept( /* noex */)>
+{
+    move_only_function() noexcept;
+    move_only_function( std::nullptr_t ) noexcept;
+
+    template<class F>
+    move_only_function( F&& f );
+
+    template<class T, class ...CArgs>
+    explicit move_only_function( in_place_type_t<T>, CArgs&& ... args );
+
+    template<class T, class U, class ...CArgs>
+    explicit move_only_function( in_place_type_t<T>,
+                                 std::initializer_list<U> il, CArgs&& ... args );
+
+    move_only_function( move_only_function const& ) = delete;
+    move_only_function( move_only_function&& ) = default;
+
+    ~move_only_function() = default;
+
+    move_only_function& operator=( move_only_function&& rhs );
+    move_only_function& operator=( std::nullptr_t ) noexcept;
+    template<class F> move_only_function& operator=( F&& f );
+
+    friend bool operator==( move_only_function const& fn, std::nullptr_t ) noexcept;
+    friend bool operator!=( move_only_function const& fn, std::nullptr_t ) noexcept;
+
+    void swap( move_only_function& rhs ) noexcept;
+    friend void swap( move_only_function& lhs, move_only_function& rhs ) noexcept;
+
+    explicit operator bool() const noexcept;
+
+    R operator()( Args... args ) /* cv */ /* ref */ noexcept( /* noex */ );
+};
+
+} // namespace compat
+} // namespace boost
+
+```
+
+## Constructors
+
+### Default Constructor
+
+```cpp
+move_only_function() noexcept;
+```
+
+[horizontal]
+Effects::
+Constructs an empty `move_only_function` which manages no object.
+
+### Null Constructor
+
+```cpp
+move_only_function( std::nullptr_t ) noexcept;
+```
+
+[horizontal]
+Effects::
+Explicitly constructs an empty `move_only_function` using a nullptr value. Equivalent to default construction.
+
+### Object Constructor
+
+```cpp
+template<class F>
+move_only_function( F&& f );
+```
+
+[horizontal]
+Effects:;; Given `using VT = decay_t<F>`, directly constructs an instance of `VT` using `forward<F>(f)` and stores it as the target object. +
+
+If `F` is an empty function pointer, pointer-to-member or specialization of `move_only_function` then the constructed `move_only_function` is empty.
+Constraints:;;
+
+--
+* `remove_cv_ref<F>` is not the same type as `move_only_function`
+* `remove_cv_ref<F>` is not a specialization of `in_place_type_t`
+* `VT` must be callable with the provided cvref qualifiers and the provided argument types
+--
+
+### In-Place Constructor
+
+```cpp
+template<class T, class ...CArgs>
+explicit move_only_function( in_place_type_t<T>, CArgs&& ... args );
+```
+
+[horizontal]
+Effects:;; Constructs an object of type `T` using the provided args directly, storing it as the target object.
+Constraints:;;
+
+--
+* `is_constructible_v<T, CArgs...>` must be true
+* `T` must be callable with the provided cvref qualifiers and the provided argument types
+--
+
+### List In-Place Constructor
+
+```cpp
+template<class T, class U, class ...CArgs>
+explicit move_only_function( in_place_type_t<T>,
+                             std::initializer_list<U> il, CArgs&& ... args );
+```
+
+[horizontal]
+Effects:;; Constructs an object of type `T` using the provided initializer_list and args directly, storing it as the target Callable.
+Constraints:;;
+
+--
+* `is_constructible_v<T, std::initializer_list<U>&, CArgs...>` must be true
+* `T` must be callable with the provided cvref qualifiers and the provided argument types
+--
+
+### Move Constructor
+
+```cpp
+move_only_function( move_only_function&& f ) = default;
+```
+
+[horizontal]
+Effects::
+Tranfers ownership of the object managed by `f` to `*this`. After this operation completes, `f` is empty and manages no object.
+
+## Assignment
+
+### Move Assignment
+
+```cpp
+move_only_function& operator=( move_only_function&& rhs );
+```
+
+[horizontal]
+Effects:;; Releases the currently managed object and takes ownership of the object managed by `rhs`, if applicable.
+`rhs` is empty after move.
+
+### Null Assigment
+
+```cpp
+move_only_function& operator=( std::nullptr_t ) noexcept;
+```
+
+[horizontal]
+Effects:;; Releases the currently managed object, if applicable.
+
+### Callable Assignment
+
+```cpp
+template<class F> move_only_function& operator=( F&& f );
+```
+
+[horizontal]
+Effects:;; Releases the currently managed object and then does the equivalent of: `move_only_function(std::forward<F>(f)).swap(*this)`.
+
+## Utility
+
+### Null Equality
+
+```cpp
+friend bool operator==( move_only_function const& fn, std::nullptr_t ) noexcept;
+friend bool operator!=( move_only_function const& fn, std::nullptr_t ) noexcept;
+```
+
+[horizontal]
+Effects:;; Returns whether or not `fn` contains a target object.
+
+### Swap
+
+```cpp
+void swap( move_only_function& rhs ) noexcept;
+friend void swap( move_only_function& lhs, move_only_function& rhs ) noexcept;
+```
+
+[horizontal]
+Effects:;; Exchanges the managed objects.
+
+## Invocation
+
+### Boolean Conversion
+
+```cpp
+explicit operator bool() const noexcept;
+```
+
+[horizontal]
+Effects:;; Returns `true` if `*this` is managing an object, or `false` if `*this` is empty.
+
+### Call Operator
+
+```cpp
+R operator()( Args... args ) /* cv */ /* ref */ noexcept( /* noex */ );
+```
+
+[horizontal]
+Preconditions:;; `*this` currently manages an object.
+Effects:;; Invokes the underlying target object. Equivalent to:
+
+--
+```cpp
+return INVOKE<R>(static_cast<F inv-quals>(f), std::forward<Args>(args)...);
+```
+
+where `f` is the target object, and _inv-quals_ is defined by the standard:
+
+* If _ref_ is empty, let _inv-quals_ be _cv&_,
+* otherwise, let _inv-quals_ be _cv ref_.
+--
--- a/doc/compat/nontype.adoc
+++ b/doc/compat/nontype.adoc
@@ -0,0 +1,58 @@
+////
+Copyright 2025 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#nontype]
+# <boost/compat/nontype.hpp>
+:idprefix: ref_nontype_
+
+## Description
+
+The header `<boost/compat/nontype.hpp>` provides the {cpp}26 variable
+template `std::nontype`.
+
+`nontype` is used for passing function pointers or member function
+pointers to `function_ref`.
+
+Since `nontype_t` and `nontype` have a template parameter of type
+`auto`, they require {cpp}17. When {cpp}17 isn't available, this
+header can still be included, but doesn't define them. (It would
+have caused an error if it did.)
+
+## Example
+
+```
+struct X
+{
+    void f(int a, int b) const noexcept;
+};
+
+int main()
+{
+    X x;
+    auto fnref = function_ref<void(int, int)>(nontype<&X::f>, &x);
+
+    fnref(1, 2); // calls x.f(1, 2)
+}
+```
+
+## Synopsis
+
+```
+namespace boost
+{
+namespace compat
+{
+
+template<auto V> struct nontype_t
+{
+    explicit nontype_t() = default;
+};
+
+template<auto V> inline constexpr nontype_t<V> nontype {};
+
+} // namespace compat
+} // namespace boost
+```
--- a/doc/compat/reference.adoc
+++ b/doc/compat/reference.adoc
@@ -0,0 +1,18 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+include::bind_back.adoc[]
+include::bind_front.adoc[]
+include::function_ref.adoc[]
+include::integer_sequence.adoc[]
+include::invoke.adoc[]
+include::latch.adoc[]
+include::mem_fn.adoc[]
+include::move_only_function.adoc[]
+include::shared_lock.adoc[]
+include::to_array.adoc[]
+include::to_underlying.adoc[]
+include::type_traits.adoc[]
--- a/doc/compat/shared_lock.adoc
+++ b/doc/compat/shared_lock.adoc
@@ -6,7 +6,7 @@ https://www.boost.org/LICENSE_1_0.txt

 [#shared_lock]
 # <boost/compat/shared_lock.hpp>
-:idprefix: shared_lock_
+:idprefix: ref_shared_lock_

 ## Description

@@ -129,7 +129,7 @@ shared_lock( mutex_type& m, std::adopt_lock_t );
 [horizontal]
 Preconditions:;; `m` must be held by a previous call to `m.lock_shared()` or a
 successful call to `m.try_lock_shared()`.
-PostConditions:;; `mutex() == std::addressof(m)` and `owns_lock() == true`.
+Postconditions:;; `mutex() == std::addressof(m)` and `owns_lock() == true`.

 ### Copy Constructor

--- a/doc/compat/to_array.adoc
+++ b/doc/compat/to_array.adoc
@@ -0,0 +1,72 @@
+////
+Copyright 2024 Ruben Perez Hidalgo
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#to_array]
+# <boost/compat/to_array.hpp>
+:idprefix: ref_to_array_
+
+## Description
+
+The header `<boost/compat/to_array.hpp>` implements, in a portable way, the C++20
+`std::to_array` function, present in the `<array>` header.
+
+`to_array` creates a `std::array` from a single-dimensional C array,
+performing an element-wise copy or move.
+
+## Example
+
+```cpp
+int input [] = {1, 2, 3};
+std::array<int, 3> output = boost::compat::to_array(input);
+assert((
+    output == std::array<int, 3>{{1, 2, 3}}
+));
+```
+
+## Synopsis
+
+```cpp
+namespace boost
+{
+namespace compat
+{
+
+template <class T, std::size_t N>
+constexpr std::array<remove_cv_t<T>, N> to_array(T (&a)[N]);
+
+template <class T, std::size_t N>
+constexpr std::array<remove_cv_t<T>, N> to_array(T (&&a)[N]);
+
+} // namespace compat
+} // namespace boost
+```
+
+## to_array
+
+```cpp
+template <class T, std::size_t N>
+constexpr std::array<remove_cv_t<T>, N> to_array(T (&&a)[N]);
+```
+
+[horizontal]
+Effects:;; Creates an array of `N` elements by copying elements in `a`.
+           For every `i` in `0, ..., N-1`, copy-initializes the i-th element
+           in the output array from `a[i]`.
+Type requirements:;; `std::is_constructible_v<remove_cv_t<T>, T&> && !std::is_array_v<T>`.
+                     Otherwise, the overload is ill-formed.
+
+
+```cpp
+template <class T, std::size_t N>
+constexpr std::array<remove_cv_t<T>, N> to_array(T (&a)[N]);
+```
+
+[horizontal]
+Effects:;; Creates an array of `N` elements by moving elements in `a`.
+           For every `i` in `0, ..., N-1`, move-initializes the i-th element
+           in the output array from `std::move(a[i])`.
+Type requirements:;; `std::is_constructible_v<remove_cv_t<T>, T&&> && !std::is_array_v<T>`.
+                     Otherwise, the overload is ill-formed.
--- a/doc/compat/to_underlying.adoc
+++ b/doc/compat/to_underlying.adoc
@@ -0,0 +1,57 @@
+////
+Copyright 2025 Braden Ganetsky
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#to_underlying]
+# <boost/compat/to_underlying.hpp>
+:idprefix: ref_to_underlying_
+
+## Description
+
+The header `<boost/compat/to_underlying.hpp>` implements the {cpp}23 function https://en.cppreference.com/w/cpp/utility/to_underlying.html[std::to_underlying].
+
+`to_underlying` is a terse way of converting a value of enumeration type to its underlying type, avoiding accidental narrowing or widening. This function is ill-formed if the given value is not of enumeration type.
+
+## Example
+
+```cpp
+enum e : std::uint16_t
+{
+    e_value = 5
+};
+auto output = boost::compat::to_underlying(e_value);
+static_assert(std::is_same<decltype(output), std::uint16_t>::value);
+assert((
+    output == 5
+));
+```
+
+## Synopsis
+
+```cpp
+namespace boost
+{
+namespace compat
+{
+
+template <class E>
+constexpr typename std::underlying_type<E>::type to_underlying(E e) noexcept;
+
+} // namespace compat
+} // namespace boost
+```
+
+## to_underlying
+
+```cpp
+template <class E>
+constexpr typename std::underlying_type<E>::type to_underlying(E e) noexcept;
+```
+
+[horizontal]
+Effects:;; Casts the value `e` of enumeration type `E` to its underlying type.
+           Equivalent to `static_cast<typename std::underlying_type<E>::type>(e)`.
+Type requirements:;; `std::is_enum<E>::value`.
+                     Otherwise, the function is ill-formed.
--- a/doc/compat/type_traits.adoc
+++ b/doc/compat/type_traits.adoc
@@ -0,0 +1,45 @@
+////
+Copyright 2024 Peter Dimov
+Distributed under the Boost Software License, Version 1.0.
+https://www.boost.org/LICENSE_1_0.txt
+////
+
+[#type_traits]
+# <boost/compat/type_traits.hpp>
+:idprefix: ref_type_traits_
+
+## Description
+
+The header `<boost/compat/type_traits.hpp>` implements some of the
+post-{cpp}11 additions to the standard header `<type_traits>`.
+
+## Synopsis
+
+```
+#include <type_traits>
+
+namespace boost
+{
+namespace compat
+{
+
+template<class T> using remove_const_t = typename std::remove_const<T>::type;
+
+template<class T> using remove_cv_t = typename std::remove_cv<T>::type;
+
+template<class T> using remove_reference_t = typename std::remove_reference<T>::type;
+
+template<class T> using remove_cvref_t = remove_cv_t<remove_reference_t<T>>;
+
+template<class T> using decay_t = typename std::decay<T>::type;
+
+template<bool B, class T = void> using enable_if_t = typename std::enable_if<B, T>::type;
+
+template<bool B, class T, class F> using conditional_t = typename std::conditional<B, T, F>::type;
+
+template<class... T> using void_t = void;
+
+
+} // namespace compat
+} // namespace boost
+```
--- a/include/boost/compat/bind_back.hpp
+++ b/include/boost/compat/bind_back.hpp
@@ -0,0 +1,72 @@
+#ifndef BOOST_COMPAT_BIND_BACK_HPP_INCLUDED
+#define BOOST_COMPAT_BIND_BACK_HPP_INCLUDED
+
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/compat/type_traits.hpp>
+#include <boost/compat/integer_sequence.hpp>
+#include <boost/compat/detail/returns.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <tuple>
+#include <utility>
+
+namespace boost {
+namespace compat {
+
+namespace detail {
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+# pragma warning(push)
+# pragma warning(disable: 4100) // 'a': unreferenced formal parameter
+#endif
+
+template<class F, class A, class... B, std::size_t... I>
+static constexpr auto invoke_bind_back_( F&& f, A&& a, index_sequence<I...>, B&&... b )
+    BOOST_COMPAT_RETURNS( compat::invoke( std::forward<F>(f), std::forward<B>(b)..., std::get<I>( std::forward<A>(a) )... ) )
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+# pragma warning(pop)
+#endif
+
+template<class F, class... A> class bind_back_
+{
+private:
+
+    F f_;
+    std::tuple<A...> a_;
+
+public:
+
+    template<class F2, class... A2>
+    constexpr bind_back_( F2&& f2, A2&&... a2 ): f_( std::forward<F2>(f2) ), a_( std::forward<A2>(a2)... ) {}
+
+public:
+
+    template<class... B> BOOST_CXX14_CONSTEXPR auto operator()( B&&... b ) &
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_back_( f_, a_, make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+
+    template<class... B> constexpr auto operator()( B&&... b ) const &
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_back_( f_, a_, make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+
+    template<class... B> BOOST_CXX14_CONSTEXPR auto operator()( B&&... b ) &&
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_back_( std::move(f_), std::move(a_), make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+
+    template<class... B> constexpr auto operator()( B&&... b ) const &&
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_back_( std::move(f_), std::move(a_), make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+};
+
+} // namespace detail
+
+template<class F, class... A> constexpr auto bind_back( F&& f, A&&... a ) -> detail::bind_back_< decay_t<F>, decay_t<A>... >
+{
+    return { std::forward<F>(f), std::forward<A>(a)... };
+}
+
+} // namespace compat
+} // namespace boost
+
+#endif // BOOST_COMPAT_BIND_BACK_HPP_INCLUDED
--- a/include/boost/compat/bind_front.hpp
+++ b/include/boost/compat/bind_front.hpp
@@ -0,0 +1,72 @@
+#ifndef BOOST_COMPAT_BIND_FRONT_HPP_INCLUDED
+#define BOOST_COMPAT_BIND_FRONT_HPP_INCLUDED
+
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/compat/type_traits.hpp>
+#include <boost/compat/integer_sequence.hpp>
+#include <boost/compat/detail/returns.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <tuple>
+#include <utility>
+
+namespace boost {
+namespace compat {
+
+namespace detail {
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+# pragma warning(push)
+# pragma warning(disable: 4100) // 'a': unreferenced formal parameter
+#endif
+
+template<class F, class A, class... B, std::size_t... I>
+static constexpr auto invoke_bind_front_( F&& f, A&& a, index_sequence<I...>, B&&... b )
+    BOOST_COMPAT_RETURNS( compat::invoke( std::forward<F>(f), std::get<I>( std::forward<A>(a) )..., std::forward<B>(b)... ) )
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+# pragma warning(pop)
+#endif
+
+template<class F, class... A> class bind_front_
+{
+private:
+
+    F f_;
+    std::tuple<A...> a_;
+
+public:
+
+    template<class F2, class... A2>
+    constexpr bind_front_( F2&& f2, A2&&... a2 ): f_( std::forward<F2>(f2) ), a_( std::forward<A2>(a2)... ) {}
+
+public:
+
+    template<class... B> BOOST_CXX14_CONSTEXPR auto operator()( B&&... b ) &
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_front_( f_, a_, make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+
+    template<class... B> constexpr auto operator()( B&&... b ) const &
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_front_( f_, a_, make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+
+    template<class... B> BOOST_CXX14_CONSTEXPR auto operator()( B&&... b ) &&
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_front_( std::move(f_), std::move(a_), make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+
+    template<class... B> constexpr auto operator()( B&&... b ) const &&
+        BOOST_COMPAT_RETURNS( detail::invoke_bind_front_( std::move(f_), std::move(a_), make_index_sequence<sizeof...(A)>(), std::forward<B>(b)... ) )
+};
+
+} // namespace detail
+
+template<class F, class... A> constexpr auto bind_front( F&& f, A&&... a ) -> detail::bind_front_< decay_t<F>, decay_t<A>... >
+{
+    return { std::forward<F>(f), std::forward<A>(a)... };
+}
+
+} // namespace compat
+} // namespace boost
+
+#endif // BOOST_COMPAT_BIND_FRONT_HPP_INCLUDED
--- a/include/boost/compat/detail/nontype.hpp
+++ b/include/boost/compat/detail/nontype.hpp
@@ -0,0 +1,37 @@
+#ifndef BOOST_COMPAT_NONTYPE_HPP_INCLUDED
+#define BOOST_COMPAT_NONTYPE_HPP_INCLUDED
+
+// Copyright 2024 Christian Mazakas
+// Copyright 2025 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config.hpp>
+
+namespace boost {
+namespace compat {
+
+namespace detail {
+
+template<class V, V v> struct nttp_holder
+{
+};
+
+} // namespace detail
+
+#if defined(__cpp_nontype_template_parameter_auto) && __cpp_nontype_template_parameter_auto >= 201606L
+
+template<auto V> struct nontype_t: public detail::nttp_holder<decltype(V), V>
+{
+    explicit nontype_t() = default;
+};
+
+template<auto V>
+BOOST_INLINE_CONSTEXPR nontype_t<V> nontype {};
+
+#endif
+
+} // namespace compat
+} // namespace boost
+
+#endif // BOOST_COMPAT_NONTYPE_HPP_INCLUDED
--- a/include/boost/compat/detail/returns.hpp
+++ b/include/boost/compat/detail/returns.hpp
@@ -0,0 +1,10 @@
+#ifndef BOOST_COMPAT_DETAIL_RETURNS_HPP_INCLUDED
+#define BOOST_COMPAT_DETAIL_RETURNS_HPP_INCLUDED
+
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#define BOOST_COMPAT_RETURNS(...) noexcept(noexcept(__VA_ARGS__)) -> decltype(__VA_ARGS__) { return __VA_ARGS__; }
+
+#endif // BOOST_COMPAT_DETAIL_RETURNS_HPP_INCLUDED
--- a/include/boost/compat/function_ref.hpp
+++ b/include/boost/compat/function_ref.hpp
@@ -0,0 +1,278 @@
+#ifndef BOOST_COMPAT_FUNCTION_REF_HPP_INCLUDED
+#define BOOST_COMPAT_FUNCTION_REF_HPP_INCLUDED
+
+// Copyright 2024 Christian Mazakas.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/detail/nontype.hpp>
+#include <boost/compat/invoke.hpp>
+#include <boost/compat/type_traits.hpp>
+
+#include <type_traits>
+#include <utility>
+
+namespace boost {
+namespace compat {
+
+template <class... S>
+struct function_ref;
+
+namespace detail {
+
+template <bool NoEx>
+union thunk_storage {
+  void* pobj_;
+  void (*pfn_)() noexcept(NoEx);
+};
+
+template <bool NoEx, class Fp, class R, class... Args>
+struct invoke_function_holder {
+  static R invoke_function(thunk_storage<NoEx> s, Args&&... args) noexcept(NoEx) {
+    auto f = reinterpret_cast<Fp>(s.pfn_);
+    return compat::invoke_r<R>(f, std::forward<Args>(args)...);
+  }
+};
+
+template <bool Const, bool NoEx, class F, class R, class... Args>
+struct invoke_object_holder {
+  static R invoke_object(thunk_storage<NoEx> s, Args&&... args) noexcept(NoEx) {
+    using T = remove_reference_t<F>;
+    using cv_T = conditional_t<Const, add_const_t<T>, T>;
+    return compat::invoke_r<R>(*static_cast<cv_T*>(s.pobj_), std::forward<Args>(args)...);
+  }
+};
+
+template <class F, F f, bool Const, bool NoEx, class R, class... Args>
+struct invoke_mem_fn_holder {
+  static R invoke_mem_fn(thunk_storage<NoEx> /* s */, Args&&... args) noexcept(NoEx) {
+    return compat::invoke_r<R>(f, std::forward<Args>(args)...);
+  }
+};
+
+template <class F, F f, class U, bool Const, bool NoEx, class R, class... Args>
+struct invoke_target_mem_fn_holder {
+  static R invoke_mem_fn(thunk_storage<NoEx> s, Args&&... args) noexcept(NoEx) {
+    using T = remove_reference_t<U>;
+    using cv_T = conditional_t<Const, add_const_t<T>, T>;
+    return compat::invoke_r<R>(f, *static_cast<cv_T*>(s.pobj_), std::forward<Args>(args)...);
+  }
+};
+
+template <class F, F f, class T, bool Const, bool NoEx, class R, class... Args>
+struct invoke_ptr_mem_fn_holder {
+  static R invoke_mem_fn(thunk_storage<NoEx> s, Args&&... args) noexcept(NoEx) {
+    using cv_T = conditional_t<Const, add_const_t<T>, T>;
+    return compat::invoke_r<R>(f, static_cast<cv_T*>(s.pobj_), std::forward<Args>(args)...);
+  }
+};
+
+template <bool Const, bool NoEx, class R, class... Args>
+struct function_ref_base {
+private:
+  thunk_storage<NoEx> thunk_ = nullptr;
+  R (*invoke_)(thunk_storage<NoEx>, Args&&...) noexcept(NoEx) = nullptr;
+
+public:
+  struct fp_tag {};
+  struct obj_tag {};
+  struct mem_fn_tag {};
+
+  template <class F>
+  function_ref_base(fp_tag, F* fn) noexcept
+      : thunk_{}, invoke_(&invoke_function_holder<NoEx, F*, R, Args...>::invoke_function) {
+    thunk_.pfn_ = reinterpret_cast<decltype(thunk_.pfn_)>(fn);
+  }
+
+  template <class F>
+  function_ref_base(obj_tag, F&& fn) noexcept
+      : thunk_{}, invoke_(&invoke_object_holder<Const, NoEx, F, R, Args...>::invoke_object) {
+    thunk_.pobj_ = const_cast<void*>(static_cast<void const*>(std::addressof(fn)));
+  }
+
+  template <class F, F f>
+  function_ref_base(mem_fn_tag, nttp_holder<F, f>)
+      : thunk_{}, invoke_(&invoke_mem_fn_holder<F, f, Const, NoEx, R, Args...>::invoke_mem_fn) {
+    thunk_.pobj_ = nullptr;
+  }
+
+  template <class F, F f, class U>
+  function_ref_base(mem_fn_tag, nttp_holder<F, f>, U&& obj)
+      : thunk_{}, invoke_(&invoke_target_mem_fn_holder<F, f, U, Const, NoEx, R, Args...>::invoke_mem_fn) {
+    thunk_.pobj_ = const_cast<void*>(static_cast<void const*>(std::addressof(obj)));
+  }
+
+  template <class F, F f, class T>
+  function_ref_base(mem_fn_tag, nttp_holder<F, f>, T* obj)
+      : thunk_{}, invoke_(&invoke_ptr_mem_fn_holder<F, f, T, Const, NoEx, R, Args...>::invoke_mem_fn) {
+    thunk_.pobj_ = const_cast<void*>(static_cast<void const*>(obj));
+  }
+
+  function_ref_base(const function_ref_base&) noexcept = default;
+  function_ref_base& operator=(const function_ref_base&) noexcept = default;
+
+  R operator()(Args... args) const noexcept(NoEx) { return this->invoke_(thunk_, std::forward<Args>(args)...); }
+};
+
+} // namespace detail
+
+template <class R, class... Args>
+struct function_ref<R(Args...)> : public detail::function_ref_base<false, false, R, Args...> {
+private:
+  using base_type = detail::function_ref_base<false, false, R, Args...>;
+  using typename base_type::fp_tag;
+  using typename base_type::mem_fn_tag;
+  using typename base_type::obj_tag;
+
+  template <class... T>
+  using is_invocable_using = boost::compat::is_invocable_r<R, T..., Args...>;
+
+public:
+  template <class F, enable_if_t<std::is_function<F>::value && is_invocable_using<F>::value, int> = 0>
+  function_ref(F* fn) noexcept : base_type(fp_tag{}, fn) {}
+
+  template <class F, class T = remove_reference_t<F>,
+            enable_if_t<!std::is_same<remove_cvref_t<F>, function_ref>::value && !std::is_member_pointer<T>::value &&
+                            is_invocable_using<T&>::value,
+                        int> = 0>
+  function_ref(F&& fn) noexcept : base_type(obj_tag{}, fn) {}
+
+  template <class F, F f, enable_if_t<is_invocable_using<F>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x) noexcept : base_type(mem_fn_tag{}, x) {}
+
+  template <class F, F f, class U, class T = remove_reference_t<U>,
+            enable_if_t<!std::is_rvalue_reference<U&&>::value && is_invocable_using<F, T&>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, U&& obj) noexcept : base_type(mem_fn_tag{}, x, std::forward<U>(obj)) {}
+
+  template <class F, F f, class T, enable_if_t<is_invocable_using<F, T*>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, T* obj) noexcept : base_type(mem_fn_tag{}, x, obj) {}
+
+  function_ref(const function_ref&) noexcept = default;
+  function_ref& operator=(const function_ref&) noexcept = default;
+
+  template <class T, enable_if_t<!std::is_same<T, function_ref>::value && !std::is_pointer<T>::value, int> = 0>
+  function_ref& operator=(T) = delete;
+};
+
+template <class R, class... Args>
+struct function_ref<R(Args...) const> : public detail::function_ref_base<true, false, R, Args...> {
+private:
+  using base_type = detail::function_ref_base<true, false, R, Args...>;
+  using typename base_type::fp_tag;
+  using typename base_type::mem_fn_tag;
+  using typename base_type::obj_tag;
+
+  template <class... T>
+  using is_invocable_using = boost::compat::is_invocable_r<R, T..., Args...>;
+
+public:
+  template <class F, enable_if_t<std::is_function<F>::value && is_invocable_using<F>::value, int> = 0>
+  function_ref(F* fn) noexcept : base_type(fp_tag{}, fn) {}
+
+  template <class F, class T = remove_reference_t<F>,
+            enable_if_t<!std::is_same<remove_cvref_t<F>, function_ref>::value && !std::is_member_pointer<T>::value &&
+                            is_invocable_using<T const&>::value,
+                        int> = 0>
+  function_ref(F&& fn) noexcept : base_type(obj_tag{}, fn) {}
+
+  template <class F, F f, enable_if_t<is_invocable_using<F>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x) noexcept : base_type(mem_fn_tag{}, x) {}
+
+  template <class F, F f, class U, class T = remove_reference_t<U>,
+            enable_if_t<!std::is_rvalue_reference<U&&>::value && is_invocable_using<F, T const&>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, U&& obj) noexcept : base_type(mem_fn_tag{}, x, std::forward<U>(obj)) {}
+
+  template <class F, F f, class T, enable_if_t<is_invocable_using<F, T const*>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, T const* obj) noexcept : base_type(mem_fn_tag{}, x, obj) {}
+
+  function_ref(const function_ref&) noexcept = default;
+  function_ref& operator=(const function_ref&) noexcept = default;
+
+  template <class T, enable_if_t<!std::is_same<T, function_ref>::value && !std::is_pointer<T>::value, int> = 0>
+  function_ref& operator=(T) = delete;
+};
+
+#if defined(__cpp_noexcept_function_type)
+
+template <class R, class... Args>
+struct function_ref<R(Args...) noexcept> : public detail::function_ref_base<false, true, R, Args...> {
+private:
+  using base_type = detail::function_ref_base<false, true, R, Args...>;
+  using typename base_type::fp_tag;
+  using typename base_type::mem_fn_tag;
+  using typename base_type::obj_tag;
+
+  template <class... T>
+  using is_invocable_using = boost::compat::is_nothrow_invocable_r<R, T..., Args...>;
+
+public:
+  template <class F, enable_if_t<std::is_function<F>::value && is_invocable_using<F>::value, int> = 0>
+  function_ref(F* fn) noexcept : base_type(fp_tag{}, fn) {}
+
+  template <class F, class T = remove_reference_t<F>,
+            enable_if_t<!std::is_same<remove_cvref_t<F>, function_ref>::value && !std::is_member_pointer<T>::value &&
+                            is_invocable_using<T&>::value,
+                        int> = 0>
+  function_ref(F&& fn) noexcept : base_type(obj_tag{}, fn) {}
+
+  template <class F, F f, enable_if_t<is_invocable_using<F>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x) noexcept : base_type(mem_fn_tag{}, x) {}
+
+  template <class F, F f, class U, class T = remove_reference_t<U>,
+            enable_if_t<!std::is_rvalue_reference<U&&>::value && is_invocable_using<F, T&>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, U&& obj) noexcept : base_type(mem_fn_tag{}, x, std::forward<U>(obj)) {}
+
+  template <class F, F f, class T, enable_if_t<is_invocable_using<F, T*>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, T* obj) noexcept : base_type(mem_fn_tag{}, x, obj) {}
+
+  function_ref(const function_ref&) noexcept = default;
+  function_ref& operator=(const function_ref&) noexcept = default;
+
+  template <class T, enable_if_t<!std::is_same<T, function_ref>::value && !std::is_pointer<T>::value, int> = 0>
+  function_ref& operator=(T) = delete;
+};
+
+template <class R, class... Args>
+struct function_ref<R(Args...) const noexcept> : public detail::function_ref_base<true, true, R, Args...> {
+private:
+  using base_type = detail::function_ref_base<true, true, R, Args...>;
+  using typename base_type::fp_tag;
+  using typename base_type::mem_fn_tag;
+  using typename base_type::obj_tag;
+
+  template <class... T>
+  using is_invocable_using = boost::compat::is_nothrow_invocable_r<R, T..., Args...>;
+
+public:
+  template <class F, enable_if_t<std::is_function<F>::value && is_invocable_using<F>::value, int> = 0>
+  function_ref(F* fn) noexcept : base_type(fp_tag{}, fn) {}
+
+  template <class F, class T = remove_reference_t<F>,
+            enable_if_t<!std::is_same<remove_cvref_t<F>, function_ref>::value && !std::is_member_pointer<T>::value &&
+                            is_invocable_using<T const&>::value,
+                        int> = 0>
+  function_ref(F&& fn) noexcept : base_type(obj_tag{}, fn) {}
+
+  template <class F, F f, enable_if_t<is_invocable_using<F>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x) noexcept : base_type(mem_fn_tag{}, x) {}
+
+  template <class F, F f, class U, class T = remove_reference_t<U>,
+            enable_if_t<!std::is_rvalue_reference<U&&>::value && is_invocable_using<F, T const&>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, U&& obj) noexcept : base_type(mem_fn_tag{}, x, std::forward<U>(obj)) {}
+
+  template <class F, F f, class T, enable_if_t<is_invocable_using<F, T const*>::value, int> = 0>
+  function_ref(detail::nttp_holder<F, f> x, T const* obj) noexcept : base_type(mem_fn_tag{}, x, obj) {}
+
+  function_ref(const function_ref&) noexcept = default;
+  function_ref& operator=(const function_ref&) noexcept = default;
+
+  template <class T, enable_if_t<!std::is_same<T, function_ref>::value && !std::is_pointer<T>::value, int> = 0>
+  function_ref& operator=(T) = delete;
+};
+
+#endif
+
+} // namespace compat
+} // namespace boost
+
+#endif // #ifndef BOOST_COMPAT_FUNCTION_REF_HPP_INCLUDED
--- a/include/boost/compat/integer_sequence.hpp
+++ b/include/boost/compat/integer_sequence.hpp
@@ -0,0 +1,120 @@
+#ifndef BOOST_COMPAT_INTEGER_SEQUENCE_HPP_INCLUDED
+#define BOOST_COMPAT_INTEGER_SEQUENCE_HPP_INCLUDED
+
+// Copyright 2015, 2017, 2019 Peter Dimov.
+//
+// Distributed under the Boost Software License, Version 1.0.
+//
+// See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt
+
+#include <cstddef>
+
+#if defined(_MSC_VER) || defined(__GNUC__)
+# pragma push_macro( "I" )
+# undef I
+#endif
+
+#if defined(__has_builtin)
+# if __has_builtin(__make_integer_seq)
+#  define BOOST_COMPAT_HAS_MAKE_INTEGER_SEQ
+# endif
+#endif
+
+namespace boost
+{
+namespace compat
+{
+
+// integer_sequence
+template<class T, T... I> struct integer_sequence
+{
+};
+
+#if defined(BOOST_COMPAT_HAS_MAKE_INTEGER_SEQ)
+
+template<class T, T N> using make_integer_sequence = __make_integer_seq<integer_sequence, T, N>;
+
+#else
+
+// detail::make_integer_sequence_impl
+namespace detail
+{
+
+// iseq_if_c
+template<bool C, class T, class E> struct iseq_if_c_impl;
+
+template<class T, class E> struct iseq_if_c_impl<true, T, E>
+{
+    using type = T;
+};
+
+template<class T, class E> struct iseq_if_c_impl<false, T, E>
+{
+    using type = E;
+};
+
+template<bool C, class T, class E> using iseq_if_c = typename iseq_if_c_impl<C, T, E>::type;
+
+// iseq_identity
+template<class T> struct iseq_identity
+{
+    using type = T;
+};
+
+template<class S1, class S2> struct append_integer_sequence;
+
+template<class T, T... I, T... J> struct append_integer_sequence<integer_sequence<T, I...>, integer_sequence<T, J...>>
+{
+    using type = integer_sequence< T, I..., ( J + sizeof...(I) )... >;
+};
+
+template<class T, T N> struct make_integer_sequence_impl;
+
+template<class T, T N> struct make_integer_sequence_impl_
+{
+private:
+
+    static_assert( N >= 0, "make_integer_sequence<T, N>: N must not be negative" );
+
+    static T const M = N / 2;
+    static T const R = N % 2;
+
+    using S1 = typename make_integer_sequence_impl<T, M>::type;
+    using S2 = typename append_integer_sequence<S1, S1>::type;
+    using S3 = typename make_integer_sequence_impl<T, R>::type;
+    using S4 = typename append_integer_sequence<S2, S3>::type;
+
+public:
+
+    using type = S4;
+};
+
+template<class T, T N> struct make_integer_sequence_impl: iseq_if_c<N == 0, iseq_identity<integer_sequence<T>>, iseq_if_c<N == 1, iseq_identity<integer_sequence<T, 0>>, make_integer_sequence_impl_<T, N> > >
+{
+};
+
+} // namespace detail
+
+// make_integer_sequence
+template<class T, T N> using make_integer_sequence = typename detail::make_integer_sequence_impl<T, N>::type;
+
+#endif // defined(BOOST_COMPAT_HAS_MAKE_INTEGER_SEQ)
+
+// index_sequence
+template<std::size_t... I> using index_sequence = integer_sequence<std::size_t, I...>;
+
+// make_index_sequence
+template<std::size_t N> using make_index_sequence = make_integer_sequence<std::size_t, N>;
+
+// index_sequence_for
+template<class... T> using index_sequence_for = make_integer_sequence<std::size_t, sizeof...(T)>;
+
+} // namespace compat
+} // namespace boost
+
+#if defined(_MSC_VER) || defined(__GNUC__)
+# pragma pop_macro( "I" )
+#endif
+
+#endif // #ifndef BOOST_COMPAT_INTEGER_SEQUENCE_HPP_INCLUDED
--- a/include/boost/compat/invoke.hpp
+++ b/include/boost/compat/invoke.hpp
@@ -0,0 +1,119 @@
+#ifndef BOOST_COMPAT_INVOKE_HPP_INCLUDED
+#define BOOST_COMPAT_INVOKE_HPP_INCLUDED
+
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/mem_fn.hpp>
+#include <boost/compat/type_traits.hpp>
+#include <boost/compat/detail/returns.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <utility>
+
+namespace boost {
+namespace compat {
+
+// invoke
+
+template<class F, class... A>
+constexpr auto invoke( F&& f, A&&... a )
+BOOST_COMPAT_RETURNS( std::forward<F>(f)(std::forward<A>(a)...) )
+
+template<class M, class T, class... A>
+constexpr auto invoke( M T::* pm, A&&... a )
+BOOST_COMPAT_RETURNS( compat::mem_fn(pm)(std::forward<A>(a)...) )
+
+// invoke_result_t
+
+template<class F, class... A> using invoke_result_t = decltype( compat::invoke( std::declval<F>(), std::declval<A>()... ) );
+
+// is_invocable
+
+namespace detail {
+
+template<class, class F, class... A> struct is_invocable_: std::false_type {};
+template<class F, class... A> struct is_invocable_< void_t<invoke_result_t<F, A...>>, F, A... >: std::true_type {};
+
+} // namespace detail
+
+template<class F, class... A> struct is_invocable: detail::is_invocable_<void, F, A...> {};
+
+// is_nothrow_invocable
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+template<class F, class... A> struct is_nothrow_invocable: std::false_type {};
+
+#else
+
+namespace detail {
+
+template<class F, class... A> struct is_nothrow_invocable_
+{
+    using type = std::integral_constant<bool, noexcept( compat::invoke( std::declval<F>(), std::declval<A>()... ) )>;
+};
+
+} // namespace detail
+
+template<class F, class... A> struct is_nothrow_invocable: conditional_t< is_invocable<F, A...>::value, detail::is_nothrow_invocable_<F, A...>, std::false_type >::type {};
+
+#endif
+
+// invoke_r
+
+template<class R, class F, class... A, class En = enable_if_t<
+    std::is_void<R>::value && is_invocable<F, A...>::value >>
+constexpr R invoke_r( F&& f, A&&... a )
+    noexcept( noexcept( static_cast<R>( compat::invoke( std::forward<F>(f), std::forward<A>(a)... ) ) ) )
+{
+    return static_cast<R>( compat::invoke( std::forward<F>(f), std::forward<A>(a)... ) );
+}
+
+template<class R, class F, class... A, class = void, class En = enable_if_t<
+    !std::is_void<R>::value && std::is_convertible< invoke_result_t<F, A...>, R >::value >>
+constexpr R invoke_r( F&& f, A&&... a )
+    noexcept( noexcept( static_cast<R>( compat::invoke( std::forward<F>(f), std::forward<A>(a)... ) ) ) )
+{
+    return compat::invoke( std::forward<F>(f), std::forward<A>(a)... );
+}
+
+// is_invocable_r
+
+namespace detail {
+
+template<class R, class F, class... A> struct is_invocable_r_: std::is_convertible< invoke_result_t<F, A...>, R > {};
+
+} // namespace detail
+
+template<class R, class F, class... A> struct is_invocable_r:
+    conditional_t< !is_invocable<F, A...>::value, std::false_type,
+    conditional_t< std::is_void<R>::value, std::true_type,
+    detail::is_invocable_r_<R, F, A...> >> {};
+
+// is_nothrow_invocable_r
+
+#if BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+template<class R, class F, class... A> struct is_nothrow_invocable_r: std::false_type {};
+
+#else
+
+namespace detail {
+
+template<class R, class F, class... A> struct is_nothrow_invocable_r_
+{
+    using type = std::integral_constant<bool, noexcept( compat::invoke_r<R>( std::declval<F>(), std::declval<A>()... ) )>;
+};
+
+} // namespace detail
+
+template<class R, class F, class... A> struct is_nothrow_invocable_r: conditional_t< is_invocable_r<R, F, A...>::value, detail::is_nothrow_invocable_r_<R, F, A...>, std::false_type >::type {};
+
+#endif
+
+} // namespace compat
+} // namespace boost
+
+#endif // BOOST_COMPAT_INVOKE_HPP_INCLUDED
--- a/include/boost/compat/mem_fn.hpp
+++ b/include/boost/compat/mem_fn.hpp
@@ -0,0 +1,78 @@
+#ifndef BOOST_COMPAT_MEM_FN_HPP_INCLUDED
+#define BOOST_COMPAT_MEM_FN_HPP_INCLUDED
+
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/type_traits.hpp>
+#include <boost/compat/detail/returns.hpp>
+#include <functional>
+
+namespace boost {
+namespace compat {
+
+namespace detail {
+
+template<class T, class U, class Td = remove_cvref_t<T>, class Ud = remove_cvref_t<U>>
+struct is_same_or_base: std::integral_constant<bool, std::is_same<Td, Ud>::value || std::is_base_of<Td, Ud>::value>
+{
+};
+
+template<class T> struct is_reference_wrapper_: std::false_type {};
+template<class T> struct is_reference_wrapper_< std::reference_wrapper<T> >: std::true_type {};
+
+template<class T> struct is_reference_wrapper: is_reference_wrapper_< remove_cvref_t<T> > {};
+
+template<class M, class T> struct _mfn
+{
+    M T::* pm_;
+
+    template<class U, class... A, class En = enable_if_t<is_same_or_base<T, U>::value>>
+    constexpr auto operator()( U&& u, A&&... a ) const
+    BOOST_COMPAT_RETURNS( (std::forward<U>(u).*pm_)( std::forward<A>(a)... ) )
+
+    template<class U, class... A, class = void, class En = enable_if_t< !is_same_or_base<T, U>::value && is_reference_wrapper<U>::value>>
+    constexpr auto operator()( U&& u, A&&... a ) const
+    BOOST_COMPAT_RETURNS( (u.get().*pm_)( std::forward<A>(a)... ) )
+
+    template<class U, class... A, class = void, class = void, class En = enable_if_t< !is_same_or_base<T, U>::value && !is_reference_wrapper<U>::value>>
+    constexpr auto operator()( U&& u, A&&... a ) const
+    BOOST_COMPAT_RETURNS( ((*std::forward<U>(u)).*pm_)( std::forward<A>(a)... ) )
+};
+
+template<class M, class T> struct _md
+{
+    M T::* pm_;
+
+    template<class U, class En = enable_if_t<is_same_or_base<T, U>::value>>
+    constexpr auto operator()( U&& u ) const
+    BOOST_COMPAT_RETURNS( std::forward<U>(u).*pm_ )
+
+    template<class U, class = void, class En = enable_if_t< !is_same_or_base<T, U>::value && is_reference_wrapper<U>::value>>
+    constexpr auto operator()( U&& u ) const
+    BOOST_COMPAT_RETURNS( u.get().*pm_ )
+
+    template<class U, class = void, class = void, class En = enable_if_t< !is_same_or_base<T, U>::value && !is_reference_wrapper<U>::value>>
+    constexpr auto operator()( U&& u ) const
+    BOOST_COMPAT_RETURNS( (*std::forward<U>(u)).*pm_ )
+};
+
+} // namespace detail
+
+template<class M, class T, class En = enable_if_t< std::is_function<M>::value > >
+constexpr auto mem_fn( M T::* pm ) noexcept -> detail::_mfn<M, T>
+{
+    return detail::_mfn<M, T>{ pm };
+}
+
+template<class M, class T, class = void, class En = enable_if_t< !std::is_function<M>::value > >
+constexpr auto mem_fn( M T::* pm ) noexcept -> detail::_md<M, T>
+{
+    return detail::_md<M, T>{ pm };
+}
+
+} // namespace compat
+} // namespace boost
+
+#endif // BOOST_COMPAT_MEM_FN_HPP_INCLUDED
--- a/include/boost/compat/move_only_function.hpp
+++ b/include/boost/compat/move_only_function.hpp
--- a/include/boost/compat/to_array.hpp
+++ b/include/boost/compat/to_array.hpp
@@ -0,0 +1,60 @@
+#ifndef BOOST_COMPAT_TO_ARRAY_HPP_INCLUDED
+#define BOOST_COMPAT_TO_ARRAY_HPP_INCLUDED
+
+// Copyright 2024 Ruben Perez Hidalgo
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/integer_sequence.hpp>
+#include <boost/compat/type_traits.hpp>
+
+#include <array>
+#include <cstddef>
+#include <type_traits>
+#include <utility>
+
+namespace boost {
+namespace compat {
+
+namespace detail {
+
+template <class T, std::size_t N, std::size_t... I>
+constexpr std::array<remove_cv_t<T>, N> to_array_lvalue(T (&a)[N], index_sequence<I...>)
+{
+    return {{a[I]...}};
+}
+
+template <class T, std::size_t N, std::size_t... I>
+constexpr std::array<remove_cv_t<T>, N> to_array_rvalue(T (&&a)[N], index_sequence<I...>)
+{
+    return {{std::move(a[I])...}};
+}
+
+}  // namespace detail
+
+template <class T, std::size_t N>
+constexpr std::array<remove_cv_t<T>, N> to_array(T (&a)[N])
+{
+    static_assert(
+        std::is_constructible<remove_cv_t<T>, T&>::value,
+        "This overload requires the resulting element type to be constructible from T&"
+    );
+    static_assert(!std::is_array<T>::value, "to_array does not work for multi-dimensional C arrays");
+    return detail::to_array_lvalue(a, make_index_sequence<N>{});
+}
+
+template <class T, std::size_t N>
+constexpr std::array<remove_cv_t<T>, N> to_array(T (&&a)[N])
+{
+    static_assert(
+        std::is_constructible<remove_cv_t<T>, T&&>::value,
+        "This overload requires the resulting element type to be constructible from T&&"
+    );
+    static_assert(!std::is_array<T>::value, "to_array does not work for multi-dimensional C arrays");
+    return detail::to_array_rvalue(static_cast<T(&&)[N]>(a), make_index_sequence<N>{});
+}
+
+}  // namespace compat
+}  // namespace boost
+
+#endif  // BOOST_COMPAT_TO_ARRAY_HPP_INCLUDED
--- a/include/boost/compat/to_underlying.hpp
+++ b/include/boost/compat/to_underlying.hpp
@@ -0,0 +1,22 @@
+#ifndef BOOST_COMPAT_TO_UNDERLYING_HPP_INCLUDED
+#define BOOST_COMPAT_TO_UNDERLYING_HPP_INCLUDED
+
+// Copyright 2025 Braden Ganetsky
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <type_traits>
+
+namespace boost {
+namespace compat {
+
+template <class E>
+constexpr typename std::underlying_type<E>::type to_underlying(E e) noexcept
+{
+    return static_cast<typename std::underlying_type<E>::type>(e);
+}
+
+}  // namespace compat
+}  // namespace boost
+
+#endif  // BOOST_COMPAT_TO_UNDERLYING_HPP_INCLUDED
--- a/include/boost/compat/type_traits.hpp
+++ b/include/boost/compat/type_traits.hpp
@@ -0,0 +1,50 @@
+#ifndef BOOST_COMPAT_TYPE_TRAITS_HPP_INCLUDED
+#define BOOST_COMPAT_TYPE_TRAITS_HPP_INCLUDED
+
+// Copyright 2024 Peter Dimov
+// Copyright 2024-2025 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <type_traits>
+
+namespace boost {
+namespace compat {
+
+template<class T> using add_lvalue_reference_t = typename std::add_lvalue_reference<T>::type;
+template<class T> using add_rvalue_reference_t = typename std::add_rvalue_reference<T>::type;
+
+template<class T> using remove_const_t = typename std::remove_const<T>::type;
+template<class T> using remove_cv_t = typename std::remove_cv<T>::type;
+template<class T> using remove_reference_t = typename std::remove_reference<T>::type;
+template<class T> using remove_cvref_t = remove_cv_t< remove_reference_t<T> >;
+template<class T> using remove_pointer_t = typename std::remove_pointer<T>::type;
+
+template<class T> using decay_t = typename std::decay<T>::type;
+
+template<bool B, class T = void> using enable_if_t = typename std::enable_if<B, T>::type;
+
+template<bool B, class T, class F> using conditional_t = typename std::conditional<B, T, F>::type;
+
+namespace detail {
+
+template<class...> struct make_void
+{
+    using type = void;
+};
+
+} // namespace detail
+
+template<class... T> using void_t = typename detail::make_void<T...>::type;
+
+template<class T> using add_const_t = typename std::add_const<T>::type;
+
+template<class T> struct type_identity
+{
+    using type = T;
+};
+
+} // namespace compat
+} // namespace boost
+
+#endif // BOOST_COMPAT_TYPE_TRAITS_HPP_INCLUDED
--- a/meta/libraries.json
+++ b/meta/libraries.json
@@ -2,7 +2,8 @@
    "key": "compat",
    "name": "Compat",
    "authors": [
-        "Peter Dimov"
+        "Peter Dimov",
+        "Christian Mazakas"
    ],
    "maintainers": [
        "Peter Dimov <pdimov -at- gmail.com>"
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -8,6 +8,7 @@ if(HAVE_BOOST_TEST)

 set(THREADS_PREFER_PTHREAD_FLAG ON)
 find_package(Threads REQUIRED)
-boost_test_jamfile(FILE Jamfile LINK_LIBRARIES Boost::compat Boost::core Threads::Threads)
+
+boost_test_jamfile(FILE Jamfile LINK_LIBRARIES Boost::compat Boost::core Boost::mp11 Threads::Threads)

 endif()
--- a/test/Jamfile
+++ b/test/Jamfile
@@ -4,7 +4,8 @@
 #  https://www.boost.org/LICENSE_1_0.txt

 import testing ;
-import ../../config/checks/config : requires ;
+import-search /boost/config/checks ;
+import config : requires ;

 project
  : default-build
@@ -20,10 +21,103 @@ project
    <toolset>msvc:<warnings-as-errors>on
    <toolset>gcc:<warnings-as-errors>on
    <toolset>clang:<warnings-as-errors>on
+
+    <library>/boost/core//boost_core
+    <library>/boost/mp11//boost_mp11
+
+    # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81601
+    # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91146
+    # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92397
+    <toolset>gcc,<undefined-sanitizer>norecover:<cxxflags>"-Wno-array-bounds"
+    <toolset>gcc,<address-sanitizer>norecover:<cxxflags>"-Wno-array-bounds"
  ;

 run quick.cpp ;

 run latch_test.cpp ;
+
 run shared_lock_test.cpp ;
 run shared_lock_test.cpp : : : <exception-handling>off : shared_lock_test_nx ;
+
+run invoke_fn_test.cpp ;
+run invoke_obj_test.cpp ;
+run invoke_mfn_test.cpp ;
+run invoke_md_test.cpp ;
+
+run mem_fn_mfn_test.cpp ;
+run mem_fn_md_test.cpp ;
+
+run invoke_fn_noexcept_test.cpp ;
+run invoke_obj_noexcept_test.cpp ;
+run invoke_mfn_noexcept_test.cpp ;
+run invoke_md_noexcept_test.cpp ;
+
+compile invoke_fn_constexpr_test.cpp ;
+compile invoke_obj_constexpr_test.cpp ;
+compile invoke_mfn_constexpr_test.cpp
+  : <toolset>gcc-4.8:<build>no <toolset>gcc-4.9:<build>no ;
+compile invoke_md_constexpr_test.cpp
+  : <toolset>gcc-4.8:<build>no <toolset>gcc-4.9:<build>no ;
+
+run invoke_result_test.cpp ;
+run is_invocable_test.cpp ;
+run is_nothrow_invocable_test.cpp ;
+
+run bind_front_fn_test.cpp ;
+run bind_front_obj_test.cpp ;
+run bind_front_mfn_test.cpp ;
+run bind_front_md_test.cpp ;
+
+compile bind_front_fn_constexpr_test.cpp ;
+compile bind_front_obj_constexpr_test.cpp ;
+compile bind_front_mfn_constexpr_test.cpp ;
+compile bind_front_md_constexpr_test.cpp ;
+
+run integer_sequence_test.cpp ;
+
+run bind_back_fn_test.cpp ;
+run bind_back_obj_test.cpp ;
+run bind_back_mfn_test.cpp ;
+run bind_back_md_test.cpp ;
+
+compile bind_back_fn_constexpr_test.cpp ;
+compile bind_back_obj_constexpr_test.cpp ;
+compile bind_back_mfn_constexpr_test.cpp ;
+compile bind_back_md_constexpr_test.cpp ;
+
+run invoke_r_fn_test.cpp ;
+run invoke_r_obj_test.cpp ;
+run invoke_r_mfn_test.cpp ;
+run invoke_r_md_test.cpp ;
+
+run invoke_r_fn_noexcept_test.cpp ;
+run invoke_r_obj_noexcept_test.cpp ;
+run invoke_r_mfn_noexcept_test.cpp ;
+run invoke_r_md_noexcept_test.cpp ;
+
+compile invoke_r_fn_constexpr_test.cpp ;
+compile invoke_r_obj_constexpr_test.cpp ;
+compile invoke_r_mfn_constexpr_test.cpp
+  : <toolset>gcc-4.8:<build>no <toolset>gcc-4.9:<build>no ;
+compile invoke_r_md_constexpr_test.cpp
+  : <toolset>gcc-4.8:<build>no <toolset>gcc-4.9:<build>no ;
+
+run is_invocable_r_test.cpp ;
+run is_nothrow_invocable_r_test.cpp ;
+
+run function_ref_fn_test.cpp ;
+run function_ref_obj_test.cpp ;
+run function_ref_mfn_test.cpp ;
+
+run function_ref_fn_noexcept_test.cpp ;
+run function_ref_mfn_noexcept_test.cpp ;
+run function_ref_obj_noexcept_test.cpp ;
+
+run move_only_function_test.cpp ;
+
+run to_array_lvalue_test.cpp ;
+run to_array_rvalue_test.cpp ;
+
+run to_underlying_test.cpp ;
+
+run nontype_test.cpp ;
--- a/test/bind_back_fn_constexpr_test.cpp
+++ b/test/bind_back_fn_constexpr_test.cpp
@@ -0,0 +1,60 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+constexpr int f0()
+{
+    return -1;
+}
+
+constexpr int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+constexpr int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+constexpr int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::bind_back( f0 )(), -1 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f1 )( 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f2 )( 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f3 )( 1, 2, 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( f1, 1 )(), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f2, 1 )( 2 ), 21 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f3, 1 )( 2, 3 ), 231 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( f2, 1, 2 )(), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f3, 1, 2 )( 3 ), 312 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( f3, 1, 2, 3 )(), 123 );
+}
+
+#endif
--- a/test/bind_back_fn_test.cpp
+++ b/test/bind_back_fn_test.cpp
@@ -0,0 +1,57 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <memory>
+
+int f0()
+{
+    return -1;
+}
+
+int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int g( std::unique_ptr<int> p, std::unique_ptr<int> q )
+{
+    return 10 * *p + *q;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::bind_back( f0 )(), -1 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f1 )( 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f2 )( 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f3 )( 1, 2, 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( f1, 1 )(), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f2, 1 )( 2 ), 21 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f3, 1 )( 2, 3 ), 231 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( f2, 1, 2 )(), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_back( f3, 1, 2 )( 3 ), 312 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( f3, 1, 2, 3 )(), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_back( g, std::unique_ptr<int>( new int(1) ) )( std::unique_ptr<int>( new int(2) ) ), 21 );
+
+    return boost::report_errors();
+}
--- a/test/bind_back_md_constexpr_test.cpp
+++ b/test/bind_back_md_constexpr_test.cpp
@@ -0,0 +1,58 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, X() )(), -1 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &x )(), -1 );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, >= 1920 && BOOST_MSVC < 1950)
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, Y() )(), -1 );
+    }
+
+    {
+        constexpr Y y = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, y )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &y )(), -1 );
+    }
+
+#endif
+}
+
+#endif
--- a/test/bind_back_md_test.cpp
+++ b/test/bind_back_md_test.cpp
@@ -0,0 +1,101 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, X() )(), -1 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, Y() )(), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, x )(), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &x )(), -1 );
+        boost::compat::bind_back( &X::m, &x )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &x )(), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::ref(x) )(), -1 );
+        boost::compat::bind_back( &X::m, std::ref(x) )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::ref(x) )(), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::cref(x) )(), -1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, y )(), -1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &y )(), -1 );
+        boost::compat::bind_back( &X::m, &y )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &y )(), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::ref(y) )(), -1 );
+        boost::compat::bind_back( &X::m, std::ref(y) )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::ref(y) )(), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::cref(y) )(), -1 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::ref(x) )(), -1 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, y )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, &y )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::m, std::ref(y) )(), -1 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/bind_back_mfn_constexpr_test.cpp
+++ b/test/bind_back_mfn_constexpr_test.cpp
@@ -0,0 +1,137 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    constexpr int f0()
+    {
+        return -1;
+    }
+
+    constexpr int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    constexpr int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( X() ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( X(), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, X(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, X(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, X(), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( X() ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( X() ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( X() ), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( Y() ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( Y(), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, Y(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, Y(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, Y(), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( Y() ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( Y() ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( Y() ), 123 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( x ), 123 );
+    }
+
+    {
+        constexpr Y x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( x ), 123 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, &x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( &x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( &x ), 123 );
+    }
+
+    {
+        constexpr Y x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, &x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( &x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( &x ), 123 );
+    }
+}
+
+#endif
--- a/test/bind_back_mfn_test.cpp
+++ b/test/bind_back_mfn_test.cpp
@@ -0,0 +1,308 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+#include <memory>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( X() ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( X(), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, X(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, X(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, X(), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( X() ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( X() ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( X() ), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( Y() ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( Y(), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, Y(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, Y(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, Y(), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( Y() ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( Y() ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( Y() ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( x ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( x ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( x ), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( x ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( x ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( x ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( &x ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, &x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, &x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( &x ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( &x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( &x ), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( &x ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, &x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, &x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( &x ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( &x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( &x ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( std::ref(x) ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, std::ref(x), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( std::ref(x) ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( std::ref(x) ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::ref(x) ), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f0 )( std::ref(x) ), -1 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1 )( std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, std::ref(x), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f1, 1 )( std::ref(x) ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( std::ref(x) ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::ref(x) ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( std::cref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, std::cref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::cref(x), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( std::cref(x) ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::cref(x) ), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( std::cref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, std::cref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::cref(x), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( std::cref(x) ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::cref(x) ), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( x ), 123 );
+    }
+
+    {
+        Y const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( x ), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, &x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( &x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( &x ), 123 );
+    }
+
+    {
+        Y const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, &x, 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( &x ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( &x ), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( std::ref(x) ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::ref(x) ), 123 );
+    }
+
+    {
+        Y const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f2, 1, 2 )( std::ref(x) ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::ref(x) ), 123 );
+    }
+
+    {
+        std::unique_ptr<X> px( new X );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::move(px) ), 123 );
+    }
+
+    {
+        std::unique_ptr<Y> px( new Y );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, 1, 2, 3 )( std::move(px) ), 123 );
+    }
+
+    {
+        std::unique_ptr<X> px( new X );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::move(px), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        std::unique_ptr<Y> px( new Y );
+        BOOST_TEST_EQ( boost::compat::bind_back( &X::f3, std::move(px), 1, 2, 3 )(), 123 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/bind_back_obj_constexpr_test.cpp
+++ b/test/bind_back_obj_constexpr_test.cpp
@@ -0,0 +1,96 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct F1
+{
+    constexpr int operator()()
+    {
+        return -1;
+    }
+
+    constexpr int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    constexpr int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct F2
+{
+    constexpr int operator()( int x1, int x2 ) &
+    {
+        return 100*x1 + 10*x2 + 1;
+    }
+
+    constexpr int operator()( int x1, int x2 ) const &
+    {
+        return 100*x1 + 10*x2 + 2;
+    }
+    constexpr int operator()( int x1, int x2 ) &&
+    {
+        return 100*x1 + 10*x2 + 3;
+    }
+    constexpr int operator()( int x1, int x2 ) const &&
+    {
+        return 100*x1 + 10*x2 + 4;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1 )( 2 ), 21 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1 )( 2, 3 ), 231 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1, 2 )( 3 ), 312 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( F2(), 9 )( 8 ), 893 );
+    }
+
+    {
+        constexpr auto fn = boost::compat::bind_back( F2(), 9 );
+        BOOST_TEST_EQ( fn( 8 ), 892 );
+    }
+
+    {
+        constexpr auto fn = boost::compat::bind_back( F2(), 9 );
+        BOOST_TEST_EQ( std::move( fn )( 8 ), 894 );
+    }
+}
+
+#endif
--- a/test/bind_back_obj_test.cpp
+++ b/test/bind_back_obj_test.cpp
@@ -0,0 +1,101 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_back.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+struct F1
+{
+    int operator()()
+    {
+        return -1;
+    }
+
+    int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct F2
+{
+    int operator()( int x1, int x2 ) &
+    {
+        return 100*x1 + 10*x2 + 1;
+    }
+
+    int operator()( int x1, int x2 ) const &
+    {
+        return 100*x1 + 10*x2 + 2;
+    }
+    int operator()( int x1, int x2 ) &&
+    {
+        return 100*x1 + 10*x2 + 3;
+    }
+    int operator()( int x1, int x2 ) const &&
+    {
+        return 100*x1 + 10*x2 + 4;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1 )( 2 ), 21 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1 )( 2, 3 ), 231 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1, 2 )( 3 ), 312 );
+
+        BOOST_TEST_EQ( boost::compat::bind_back( F1(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_back( F2(), 9 )( 8 ), 893 );
+    }
+
+    {
+        auto fn = boost::compat::bind_back( F2(), 9 );
+        BOOST_TEST_EQ( fn( 8 ), 891 );
+    }
+
+    {
+        auto const fn = boost::compat::bind_back( F2(), 9 );
+        BOOST_TEST_EQ( fn( 8 ), 892 );
+    }
+
+    {
+        auto fn = boost::compat::bind_back( F2(), 9 );
+        BOOST_TEST_EQ( std::move( fn )( 8 ), 893 );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_GCC, < 40900)
+
+    {
+        auto const fn = boost::compat::bind_back( F2(), 9 );
+        BOOST_TEST_EQ( std::move( fn )( 8 ), 894 );
+    }
+
+#endif
+
+    return boost::report_errors();
+}
--- a/test/bind_front_fn_constexpr_test.cpp
+++ b/test/bind_front_fn_constexpr_test.cpp
@@ -0,0 +1,60 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+constexpr int f0()
+{
+    return -1;
+}
+
+constexpr int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+constexpr int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+constexpr int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::bind_front( f0 )(), -1 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f1 )( 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f2 )( 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f3 )( 1, 2, 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( f1, 1 )(), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f2, 1 )( 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f3, 1 )( 2, 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( f2, 1, 2 )(), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f3, 1, 2 )( 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( f3, 1, 2, 3 )(), 123 );
+}
+
+#endif
--- a/test/bind_front_fn_test.cpp
+++ b/test/bind_front_fn_test.cpp
@@ -0,0 +1,57 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <memory>
+
+int f0()
+{
+    return -1;
+}
+
+int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int g( std::unique_ptr<int> p, std::unique_ptr<int> q )
+{
+    return 10 * *p + *q;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::bind_front( f0 )(), -1 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f1 )( 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f2 )( 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f3 )( 1, 2, 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( f1, 1 )(), 1 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f2, 1 )( 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f3, 1 )( 2, 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( f2, 1, 2 )(), 12 );
+    BOOST_TEST_EQ( boost::compat::bind_front( f3, 1, 2 )( 3 ), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( f3, 1, 2, 3 )(), 123 );
+
+    BOOST_TEST_EQ( boost::compat::bind_front( g, std::unique_ptr<int>( new int(1) ) )( std::unique_ptr<int>( new int(2) ) ), 12 );
+
+    return boost::report_errors();
+}
--- a/test/bind_front_md_constexpr_test.cpp
+++ b/test/bind_front_md_constexpr_test.cpp
@@ -0,0 +1,58 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, X() )(), -1 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &x )(), -1 );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, >= 1920 && BOOST_MSVC < 1950)
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, Y() )(), -1 );
+    }
+
+    {
+        constexpr Y y = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, y )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &y )(), -1 );
+    }
+
+#endif
+}
+
+#endif
--- a/test/bind_front_md_test.cpp
+++ b/test/bind_front_md_test.cpp
@@ -0,0 +1,101 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, X() )(), -1 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, Y() )(), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, x )(), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &x )(), -1 );
+        boost::compat::bind_front( &X::m, &x )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &x )(), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::ref(x) )(), -1 );
+        boost::compat::bind_front( &X::m, std::ref(x) )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::ref(x) )(), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::cref(x) )(), -1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, y )(), -1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &y )(), -1 );
+        boost::compat::bind_front( &X::m, &y )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &y )(), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::ref(y) )(), -1 );
+        boost::compat::bind_front( &X::m, std::ref(y) )() = +1;
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::ref(y) )(), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::cref(y) )(), -1 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::ref(x) )(), -1 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, y )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, &y )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::m, std::ref(y) )(), -1 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/bind_front_mfn_constexpr_test.cpp
+++ b/test/bind_front_mfn_constexpr_test.cpp
@@ -0,0 +1,167 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    constexpr int f0()
+    {
+        return -1;
+    }
+
+    constexpr int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    constexpr int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( X(), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, X() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, X() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, X() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, X(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, X(), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X(), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, X(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X(), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, Y() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, Y() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, Y() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, Y() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, Y(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y(), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y(), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y(), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        constexpr Y x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        constexpr Y x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2, 3 )(), 123 );
+    }
+}
+
+#endif
--- a/test/bind_front_mfn_test.cpp
+++ b/test/bind_front_mfn_test.cpp
@@ -0,0 +1,378 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+#include <memory>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( X(), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, X() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, X() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, X() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, X(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, X(), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X(), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, X(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X(), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, X(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, Y() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, Y() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, Y() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, Y() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, Y(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y(), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y(), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, Y(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y(), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, Y(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( x ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, x )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, &x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, &x )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, &x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( std::ref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, std::ref(x) )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, std::ref(x) )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x) )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x) )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, std::ref(x), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( std::cref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::cref(x) )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x) )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::cref(x), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::cref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( x ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, x )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, &x )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, &x )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, &x, 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0 )( std::ref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1 )( std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f0, std::ref(x) )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, std::ref(x) )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x) )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x) )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f1, std::ref(x), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y x;
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( std::cref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::cref(x) )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x) )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::cref(x), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::cref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::cref(x), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x) )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x) )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, &x, 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, &x, 1, 2, 3 )(), 123 );
+    }
+
+    {
+        Y const x = {};
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x) )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x) )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f2, std::ref(x), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::ref(x), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        std::unique_ptr<X> px( new X );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::move(px), 1 )( 2, 3 ), 123 );
+    }
+
+    {
+        std::unique_ptr<Y> px( new Y );
+        BOOST_TEST_EQ( boost::compat::bind_front( &X::f3, std::move(px), 1 )( 2, 3 ), 123 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/bind_front_obj_constexpr_test.cpp
+++ b/test/bind_front_obj_constexpr_test.cpp
@@ -0,0 +1,96 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if defined(BOOST_NO_CXX14_CONSTEXPR)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped because BOOST_NO_CXX14_CONSTEXPR is defined" )
+int main() {}
+
+#else
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct F1
+{
+    constexpr int operator()()
+    {
+        return -1;
+    }
+
+    constexpr int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    constexpr int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct F2
+{
+    constexpr int operator()( int x1, int x2 ) &
+    {
+        return 100*x1 + 10*x2 + 1;
+    }
+
+    constexpr int operator()( int x1, int x2 ) const &
+    {
+        return 100*x1 + 10*x2 + 2;
+    }
+    constexpr int operator()( int x1, int x2 ) &&
+    {
+        return 100*x1 + 10*x2 + 3;
+    }
+    constexpr int operator()( int x1, int x2 ) const &&
+    {
+        return 100*x1 + 10*x2 + 4;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( F2(), 9 )( 8 ), 983 );
+    }
+
+    {
+        constexpr auto fn = boost::compat::bind_front( F2(), 9 );
+        BOOST_TEST_EQ( fn( 8 ), 982 );
+    }
+
+    {
+        constexpr auto fn = boost::compat::bind_front( F2(), 9 );
+        BOOST_TEST_EQ( std::move( fn )( 8 ), 984 );
+    }
+}
+
+#endif
--- a/test/bind_front_obj_test.cpp
+++ b/test/bind_front_obj_test.cpp
@@ -0,0 +1,101 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/bind_front.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+struct F1
+{
+    int operator()()
+    {
+        return -1;
+    }
+
+    int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct F2
+{
+    int operator()( int x1, int x2 ) &
+    {
+        return 100*x1 + 10*x2 + 1;
+    }
+
+    int operator()( int x1, int x2 ) const &
+    {
+        return 100*x1 + 10*x2 + 2;
+    }
+    int operator()( int x1, int x2 ) &&
+    {
+        return 100*x1 + 10*x2 + 3;
+    }
+    int operator()( int x1, int x2 ) const &&
+    {
+        return 100*x1 + 10*x2 + 4;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )(), -1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )( 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )( 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1() )( 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1 )(), 1 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1 )( 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1 )( 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1, 2 )(), 12 );
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1, 2 )( 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::bind_front( F1(), 1, 2, 3 )(), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::bind_front( F2(), 9 )( 8 ), 983 );
+    }
+
+    {
+        auto fn = boost::compat::bind_front( F2(), 9 );
+        BOOST_TEST_EQ( fn( 8 ), 981 );
+    }
+
+    {
+        auto const fn = boost::compat::bind_front( F2(), 9 );
+        BOOST_TEST_EQ( fn( 8 ), 982 );
+    }
+
+    {
+        auto fn = boost::compat::bind_front( F2(), 9 );
+        BOOST_TEST_EQ( std::move( fn )( 8 ), 983 );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_GCC, < 40900)
+
+    {
+        auto const fn = boost::compat::bind_front( F2(), 9 );
+        BOOST_TEST_EQ( std::move( fn )( 8 ), 984 );
+    }
+
+#endif
+
+    return boost::report_errors();
+}
--- a/test/cmake_install_test/CMakeLists.txt
+++ b/test/cmake_install_test/CMakeLists.txt
@@ -14,4 +14,4 @@ target_link_libraries(quick Boost::compat)
 enable_testing()
 add_test(quick quick)

-add_custom_target(check COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)
+add_custom_target(check VERBATIM COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)
--- a/test/cmake_subdir_test/CMakeLists.txt
+++ b/test/cmake_subdir_test/CMakeLists.txt
@@ -18,4 +18,4 @@ target_link_libraries(quick Boost::compat)
 enable_testing()
 add_test(quick quick)

-add_custom_target(check COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)
+add_custom_target(check VERBATIM COMMAND ${CMAKE_CTEST_COMMAND} --output-on-failure -C $<CONFIG>)
--- a/test/function_ref_fn_noexcept_test.cpp
+++ b/test/function_ref_fn_noexcept_test.cpp
@@ -0,0 +1,165 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config/pragma_message.hpp>
+
+#if !defined(__cpp_noexcept_function_type)
+
+BOOST_PRAGMA_MESSAGE("Test skipped, __cpp_noexcept_function_type is not defined")
+int main() {}
+
+#else
+
+#include <boost/compat/function_ref.hpp>
+#include <boost/config.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+int f0() { return -1; }
+
+int f1(int x1) noexcept { return x1; }
+int g1(int x1) noexcept { return x1 * 2; }
+
+int f2(int x1, int x2) { return 10 * x1 + x2; }
+
+int f3(int x1, int x2, int x3) noexcept { return 100 * x1 + 10 * x2 + x3; }
+
+int g(std::unique_ptr<int> p, std::unique_ptr<int> q) { return 10 * *p + *q; }
+
+struct X {
+  int v = 0;
+
+  X() = default;
+  X(int v_) noexcept : v{v_} {}
+};
+
+struct Y {
+  int v = 0;
+
+  Y() = default;
+  explicit Y(int v_) : v{v_} {}
+};
+
+struct Z {
+  int v = 0;
+
+  Z() = default;
+  Z(int v_) : v{v_} {}
+};
+
+namespace compat = boost::compat;
+
+int main() {
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int() noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int() const noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int) noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int) const noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int) noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int) const noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int, int) noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int, int) const noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<X(int, int, int) noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<X(int, int, int) const noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<void(int, int, int) noexcept>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<void(int, int, int) const noexcept>>));
+
+  struct W {
+    int w_;
+  };
+
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int() noexcept>, W>));
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int() const noexcept>, W>));
+
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int() noexcept>, compat::function_ref<int()>>));
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int()>, compat::function_ref<int() noexcept>>));
+  BOOST_TEST_TRAIT_FALSE(
+      (std::is_assignable<compat::function_ref<int() const noexcept>, compat::function_ref<int() const>>));
+
+  BOOST_TEST_TRAIT_FALSE(
+      (std::is_assignable<compat::function_ref<int() noexcept>, compat::function_ref<int(int) noexcept>>));
+  BOOST_TEST_TRAIT_FALSE(
+      (std::is_assignable<compat::function_ref<int(int) noexcept>, compat::function_ref<int() noexcept>>));
+
+  // f0
+  {
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int() noexcept>, decltype(f0)>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int() const noexcept>, decltype(f0)>));
+  }
+
+  // f1
+  {
+    compat::function_ref<int(int) noexcept> fv1(f1);
+    BOOST_TEST_EQ(fv1(1), 1);
+
+    compat::function_ref<int(int) const noexcept> fv2(f1);
+    BOOST_TEST_EQ(fv2(1), 1);
+  }
+
+  // f2
+  {
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(int, int) noexcept>, decltype(f2)>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(int, int) const noexcept>, decltype(f2)>));
+  }
+
+  // f3
+  {
+    compat::function_ref<int(int, int, int) noexcept> fv1(f3);
+    BOOST_TEST_EQ(fv1(1, 2, 3), 123);
+
+    compat::function_ref<int(int, int, int) const noexcept> fv2(f3);
+    BOOST_TEST_EQ(fv2(1, 2, 3), 123);
+  }
+
+  // g
+  {
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(std::unique_ptr<int>, std::unique_ptr<int>) noexcept>,
+                               decltype(g)>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(std::unique_ptr<int>, std::unique_ptr<int>) const noexcept>,
+                               decltype(g)>));
+  }
+
+  // invoke_r
+  {
+    compat::function_ref<X(int, int, int) noexcept> fv1(f3);
+    BOOST_TEST_EQ(fv1(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int) noexcept>, decltype(f3)>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Z(int, int, int) noexcept>, decltype(f3)>));
+
+    compat::function_ref<X(int, int, int) const noexcept> fv2(f3);
+    BOOST_TEST_EQ(fv2(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<Y(int, int, int) const noexcept>, decltype(f3)>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<Z(int, int, int) const noexcept>, decltype(f3)>));
+
+    compat::function_ref<void(int, int, int) noexcept> fv3(f3);
+    fv3(1, 2, 3);
+
+    compat::function_ref<void(int, int, int) const noexcept> fv4(f3);
+    fv4(1, 2, 3);
+  }
+
+  // copy construct, copy assign
+  {
+    compat::function_ref<int(int) noexcept> fv(f1);
+    compat::function_ref<int(int) noexcept> fv2(fv);
+    BOOST_TEST_EQ(fv(42), fv2(42));
+
+    fv2 = g1;
+    BOOST_TEST_EQ(fv2(12), 24);
+
+    compat::function_ref<int(int) const noexcept> cfv(f1);
+    compat::function_ref<int(int) const noexcept> cfv2(cfv);
+    BOOST_TEST_EQ(cfv(42), cfv2(42));
+
+    cfv2 = g1;
+    BOOST_TEST_EQ(cfv2(24), 48);
+  }
+
+  return boost::report_errors();
+}
+
+#endif
--- a/test/function_ref_fn_test.cpp
+++ b/test/function_ref_fn_test.cpp
@@ -0,0 +1,184 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+#pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/function_ref.hpp>
+
+#include <boost/config.hpp>
+#include <boost/config/pragma_message.hpp>
+#include <boost/config/workaround.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+int f0() { return -1; }
+int g0() { return 7331; }
+
+int f1(int x1) noexcept { return x1; }
+
+int f2(int x1, int x2) { return 10 * x1 + x2; }
+
+int f3(int x1, int x2, int x3) noexcept { return 100 * x1 + 10 * x2 + x3; }
+
+int g(std::unique_ptr<int> p, std::unique_ptr<int> q) { return 10 * *p + *q; }
+
+struct X {
+  int v = 0;
+
+  X() = default;
+  X(int v_) noexcept : v{v_} {}
+};
+
+struct Y {
+  int v = 0;
+
+  Y() = default;
+  explicit Y(int v_) : v{v_} {}
+};
+
+struct Z {
+  int v = 0;
+
+  Z() = default;
+  Z(int v_) : v{v_} {}
+};
+
+namespace compat = boost::compat;
+
+int main() {
+
+#if !defined(BOOST_NO_CXX11_HDR_TYPE_TRAITS)
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int()>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int() const>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int)>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int) const>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int)>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int) const>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int, int)>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<int(int, int, int) const>>));
+  BOOST_TEST_TRAIT_TRUE(
+      (std::is_trivially_copyable<compat::function_ref<int(std::unique_ptr<int>, std::unique_ptr<int>)>>));
+  BOOST_TEST_TRAIT_TRUE(
+      (std::is_trivially_copyable<compat::function_ref<int(std::unique_ptr<int>, std::unique_ptr<int>) const>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<X(int, int, int)>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<X(int, int, int) const>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<void(int, int, int)>>));
+  BOOST_TEST_TRAIT_TRUE((std::is_trivially_copyable<compat::function_ref<void(int, int, int) const>>));
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+  struct W {
+    int w_;
+  };
+
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int()>, W>));
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int() const>, W>));
+
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int()>, compat::function_ref<int() const>>));
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int() const>, compat::function_ref<int()>>));
+
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int()>, compat::function_ref<int(int)>>));
+  BOOST_TEST_TRAIT_FALSE((std::is_assignable<compat::function_ref<int(int)>, compat::function_ref<int()>>));
+#endif
+
+#else
+  BOOST_PRAGMA_MESSAGE("<type_traits> is incomplete, skipping is_trivially_copyable checks")
+#endif
+
+  // f0
+  {
+    compat::function_ref<int()> fv1(f0);
+    BOOST_TEST_EQ(fv1(), -1);
+
+    compat::function_ref<int() const> fv2(f0);
+    BOOST_TEST_EQ(fv2(), -1);
+  }
+
+  // f1
+  {
+    int x = 1;
+    compat::function_ref<int(int)> fv1(f1);
+    BOOST_TEST_EQ(fv1(x), 1);
+
+    compat::function_ref<int(int) const> fv2(f1);
+    BOOST_TEST_EQ(fv2(1), 1);
+  }
+
+  // f2
+  {
+    compat::function_ref<int(int, int)> fv1(f2);
+    BOOST_TEST_EQ(fv1(1, 2), 12);
+
+    compat::function_ref<int(int, int) const> fv2(f2);
+    BOOST_TEST_EQ(fv2(1, 2), 12);
+  }
+
+  // f3
+  {
+    compat::function_ref<int(int, int, int)> fv1(f3);
+    BOOST_TEST_EQ(fv1(1, 2, 3), 123);
+
+    compat::function_ref<int(int, int, int) const> fv2(f3);
+    BOOST_TEST_EQ(fv2(1, 2, 3), 123);
+  }
+
+  // g
+  {
+    using S1 = int(std::unique_ptr<int>, std::unique_ptr<int>);
+    using S2 = int(std::unique_ptr<int>, std::unique_ptr<int>) const;
+
+    compat::function_ref<S1> fv1(g);
+    {
+      auto p = std::unique_ptr<int>(new int{1});
+      auto q = std::unique_ptr<int>(new int{2});
+      BOOST_TEST_EQ(fv1(std::move(p), std::move(q)), 12);
+    }
+
+    compat::function_ref<S2> fv2(g);
+    {
+      auto p = std::unique_ptr<int>(new int{130});
+      auto q = std::unique_ptr<int>(new int{37});
+      BOOST_TEST_EQ(fv1(std::move(p), std::move(q)), 1337);
+    }
+  }
+
+  // invoke_r
+  {
+    compat::function_ref<X(int, int, int)> fv1(f3);
+    BOOST_TEST_EQ(fv1(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int)>, decltype(f3)>));
+    BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<Z(int, int, int)>, decltype(f3)>));
+
+    compat::function_ref<X(int, int, int) const> fv2(f3);
+    BOOST_TEST_EQ(fv2(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int) const>, decltype(f3)>));
+    BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<Z(int, int, int) const>, decltype(f3)>));
+
+    compat::function_ref<void(int, int, int)> fv3(f3);
+    fv3(1, 2, 3);
+
+    compat::function_ref<void(int, int, int) const> fv4(f3);
+    fv4(1, 2, 3);
+  }
+
+  // copy construct, copy assign
+  {
+    compat::function_ref<int()> fv(f0);
+    compat::function_ref<int()> fv2(fv);
+    BOOST_TEST_EQ(fv(), fv2());
+
+    fv2 = g0;
+    BOOST_TEST_EQ(fv2(), 7331);
+
+    compat::function_ref<int() const> cfv(f0);
+    compat::function_ref<int() const> cfv2(cfv);
+    BOOST_TEST_EQ(cfv(), cfv2());
+
+    cfv2 = g0;
+    BOOST_TEST_EQ(cfv2(), 7331);
+  }
+
+  return boost::report_errors();
+}
--- a/test/function_ref_mfn_noexcept_test.cpp
+++ b/test/function_ref_mfn_noexcept_test.cpp
@@ -0,0 +1,186 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+#pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/function_ref.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <memory>
+#include <type_traits>
+
+#if defined(__cpp_nontype_template_parameter_auto) && __cpp_nontype_template_parameter_auto >= 201606L
+
+#define NONTYPE(fn) compat::nontype<fn>
+#define NONTYPE_T(fn) compat::nontype_t<fn>
+
+#else
+
+#define NONTYPE(fn) compat::detail::nttp_holder<decltype(fn), fn>{}
+#define NONTYPE_T(fn) compat::detail::nttp_holder<decltype(fn), fn>
+
+#endif
+
+struct F1 {
+  std::unique_ptr<int> p_;
+
+  F1() : p_(new int(1)) {}
+
+  int m1() { return *p_ + -1; }
+  int m2(int x1) noexcept { return 10 * *p_ + x1; }
+  int m3(int x1, int x2) const { return 100 * *p_ + 10 * x1 + x2; }
+  int m4(int x1, int x2, int x3) const noexcept { return 1000 * *p_ + 100 * x1 + 10 * x2 + x3; }
+};
+
+namespace compat = boost::compat;
+
+int main() {
+  {
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1&) noexcept>, NONTYPE_T(&F1::m1)>));
+#endif
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(F1&, int) noexcept>, NONTYPE_T(&F1::m2)>));
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1&, int, int) noexcept>, NONTYPE_T(&F1::m3)>));
+#endif
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(F1&, int, int, int) noexcept>, NONTYPE_T(&F1::m4)>));
+  }
+
+  {
+    F1 f1;
+
+    compat::function_ref<int(F1&, int) noexcept> fn2(NONTYPE(&F1::m2));
+    BOOST_TEST_EQ(fn2(f1, 2), 12);
+
+    compat::function_ref<int(F1&, int, int, int) noexcept> fn4(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f1, 2, 3, 4), 1234);
+  }
+
+  {
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1&) const noexcept>, NONTYPE_T(&F1::m1)>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1&, int, int) const noexcept>, NONTYPE_T(&F1::m3)>));
+#endif
+
+    F1 f1;
+
+    compat::function_ref<int(F1&, int) const noexcept> fn2(NONTYPE(&F1::m2));
+    BOOST_TEST_EQ(fn2(f1, 2), 12);
+
+    compat::function_ref<int(F1&, int, int, int) const noexcept> fn4(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f1, 2, 3, 4), 1234);
+  }
+
+  {
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1 const&) noexcept>, NONTYPE_T(&F1::m1)>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1 const&, int) noexcept>, NONTYPE_T(&F1::m2)>));
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1 const&, int, int) noexcept>, NONTYPE_T(&F1::m3)>));
+#endif
+
+    F1 f1;
+
+    compat::function_ref<int(F1 const&, int, int, int) noexcept> fn4(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f1, 2, 3, 4), 1234);
+  }
+
+  {
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int() noexcept>, NONTYPE_T(&F1::m1), F1&>));
+#endif
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(int) noexcept>, NONTYPE_T(&F1::m2), F1&>));
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int, int) noexcept>, NONTYPE_T(&F1::m3), F1&>));
+#endif
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(int, int, int) noexcept>, NONTYPE_T(&F1::m4), F1&>));
+
+    F1 f1;
+
+    compat::function_ref<int(int) noexcept> fn2(NONTYPE(&F1::m2), f1);
+    BOOST_TEST_EQ(fn2(2), 12);
+
+    compat::function_ref<int(int, int, int) noexcept> fn4(NONTYPE(&F1::m4), f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+  }
+
+  {
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int() const noexcept>, NONTYPE_T(&F1::m1), F1 const&>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int) const noexcept>, NONTYPE_T(&F1::m2), F1 const&>));
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(int, int) const noexcept>,
+                                                  NONTYPE_T(&F1::m3), F1 const&>));
+#endif
+
+    F1 f1;
+
+    compat::function_ref<int(int, int, int) const noexcept> fn4(NONTYPE(&F1::m4), f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+
+    auto const& f1_2 = f1;
+    compat::function_ref<int(int, int, int) const noexcept> fn4_2(NONTYPE(&F1::m4), f1_2);
+    BOOST_TEST_EQ(fn4_2(2, 3, 4), 1234);
+  }
+
+  {
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int() noexcept>, NONTYPE_T(&F1::m1), F1*>));
+#endif
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(int) noexcept>, NONTYPE_T(&F1::m2), F1*>));
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int, int) noexcept>, NONTYPE_T(&F1::m3), F1*>));
+#endif
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(int, int, int) noexcept>, NONTYPE_T(&F1::m4), F1*>));
+
+    F1 f1;
+
+    compat::function_ref<int(int) noexcept> fn2(NONTYPE(&F1::m2), &f1);
+    BOOST_TEST_EQ(fn2(2), 12);
+
+    compat::function_ref<int(int, int, int) noexcept> fn4(NONTYPE(&F1::m4), &f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+  }
+
+  {
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int() const noexcept>, NONTYPE_T(&F1::m1), F1 const*>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int) const noexcept>, NONTYPE_T(&F1::m2), F1 const*>));
+#if defined(__cpp_noexcept_function_types)
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(int, int) const noexcept>,
+                                                  NONTYPE_T(&F1::m3), F1 const*>));
+#endif
+
+    F1 const f1;
+
+    compat::function_ref<int(int, int, int) const noexcept> fn4(NONTYPE(&F1::m4), &f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+
+    auto const& f1_2 = f1;
+    compat::function_ref<int(int, int, int) const noexcept> fn4_2(NONTYPE(&F1::m4), &f1_2);
+    BOOST_TEST_EQ(fn4_2(2, 3, 4), 1234);
+  }
+
+  return boost::report_errors();
+}
--- a/test/function_ref_mfn_test.cpp
+++ b/test/function_ref_mfn_test.cpp
@@ -0,0 +1,179 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+#pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/function_ref.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <memory>
+#include <type_traits>
+
+#if defined(__cpp_nontype_template_parameter_auto) && __cpp_nontype_template_parameter_auto >= 201606L
+
+#define NONTYPE(fn) compat::nontype<fn>
+#define NONTYPE_T(fn) compat::nontype_t<fn>
+
+#else
+
+#define NONTYPE(fn) compat::detail::nttp_holder<decltype(fn), fn>{}
+#define NONTYPE_T(fn) compat::detail::nttp_holder<decltype(fn), fn>
+
+#endif
+
+struct F1 {
+  std::unique_ptr<int> p_;
+  int q_ = 1337;
+
+  F1() : p_(new int(1)) {}
+
+  int m1() { return *p_ + -1; }
+  int m2(int x1) noexcept { return 10 * *p_ + x1; }
+  int m3(int x1, int x2) const { return 100 * *p_ + 10 * x1 + x2; }
+  int m4(int x1, int x2, int x3) const noexcept { return 1000 * *p_ + 100 * x1 + 10 * x2 + x3; }
+};
+
+namespace compat = boost::compat;
+
+int main() {
+  {
+    F1 f1;
+
+    compat::function_ref<int(F1&)> fn1(NONTYPE(&F1::m1));
+    BOOST_TEST_EQ(fn1(f1), 0);
+
+    int x = 2;
+    compat::function_ref<int(F1&, int)> fn2(NONTYPE(&F1::m2));
+    BOOST_TEST_EQ(fn2(f1, x), 12);
+
+    compat::function_ref<int(F1&, int, int)> fn3(NONTYPE(&F1::m3));
+    BOOST_TEST_EQ(fn3(f1, 2, 3), 123);
+
+    compat::function_ref<int(F1&, int, int, int)> fn4(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f1, 2, 3, 4), 1234);
+
+    compat::function_ref<int(F1&)> a1(NONTYPE(&F1::q_));
+    BOOST_TEST_EQ(a1(f1), 1337);
+  }
+
+  {
+    F1 f1;
+
+    compat::function_ref<int(F1&) const> fn1(NONTYPE(&F1::m1));
+    BOOST_TEST_EQ(fn1(f1), 0);
+
+    compat::function_ref<int(F1&, int) const> fn2(NONTYPE(&F1::m2));
+    BOOST_TEST_EQ(fn2(f1, 2), 12);
+
+    compat::function_ref<int(F1&, int, int) const> fn3(NONTYPE(&F1::m3));
+    BOOST_TEST_EQ(fn3(f1, 2, 3), 123);
+
+    compat::function_ref<int(F1&, int, int, int) const> fn4(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f1, 2, 3, 4), 1234);
+  }
+
+  {
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(F1 const&)>, NONTYPE_T(&F1::m1)>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(F1 const&, int)>, NONTYPE_T(&F1::m2)>));
+
+    F1 f1;
+
+    compat::function_ref<int(F1 const&, int, int) const> fn3(NONTYPE(&F1::m3));
+    BOOST_TEST_EQ(fn3(f1, 2, 3), 123);
+
+    compat::function_ref<int(F1 const&, int, int, int) const> fn4(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f1, 2, 3, 4), 1234);
+
+    auto const& f2 = f1;
+
+    compat::function_ref<int(F1 const&, int, int) const> fn23(NONTYPE(&F1::m3));
+    BOOST_TEST_EQ(fn3(f2, 2, 3), 123);
+
+    compat::function_ref<int(F1 const&, int, int, int) const> fn24(NONTYPE(&F1::m4));
+    BOOST_TEST_EQ(fn4(f2, 2, 3, 4), 1234);
+  }
+
+  {
+    BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<int(int)>, NONTYPE_T(&F1::m2), F1&>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int)>, NONTYPE_T(&F1::m2), F1 const&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(int)>, NONTYPE_T(&F1::m2), F1&&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int(int)>, NONTYPE_T(&F1::m2), F1>));
+
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(int, int) const>, NONTYPE_T(&F1::m3), F1&>));
+    BOOST_TEST_TRAIT_TRUE(
+        (std::is_constructible<compat::function_ref<int(int, int) const>, NONTYPE_T(&F1::m3), F1 const&>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int, int) const>, NONTYPE_T(&F1::m3), F1&&>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int, int) const>, NONTYPE_T(&F1::m3), F1>));
+  }
+
+  {
+    F1 f1;
+
+    compat::function_ref<int()> fn1(NONTYPE(&F1::m1), f1);
+    BOOST_TEST_EQ(fn1(), 0);
+
+    compat::function_ref<int(int)> fn2(NONTYPE(&F1::m2), f1);
+    BOOST_TEST_EQ(fn2(2), 12);
+
+    compat::function_ref<int(int, int)> fn3(NONTYPE(&F1::m3), f1);
+    BOOST_TEST_EQ(fn3(2, 3), 123);
+
+    compat::function_ref<int(int, int, int)> fn4(NONTYPE(&F1::m4), f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+  }
+
+  {
+    F1 const f1;
+
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<int() const>, NONTYPE_T(&F1::m1), F1&>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int) const>, NONTYPE_T(&F1::m2), F1&>));
+
+    compat::function_ref<int(int, int) const> fn3(NONTYPE(&F1::m3), f1);
+    BOOST_TEST_EQ(fn3(2, 3), 123);
+
+    compat::function_ref<int(int, int, int) const> fn4(NONTYPE(&F1::m4), f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+  }
+
+  {
+    F1 f1;
+
+    compat::function_ref<int()> fn1(NONTYPE(&F1::m1), &f1);
+    BOOST_TEST_EQ(fn1(), 0);
+
+    compat::function_ref<int(int)> fn2(NONTYPE(&F1::m2), &f1);
+    BOOST_TEST_EQ(fn2(2), 12);
+
+    compat::function_ref<int(int, int)> fn3(NONTYPE(&F1::m3), &f1);
+    BOOST_TEST_EQ(fn3(2, 3), 123);
+
+    compat::function_ref<int(int, int, int)> fn4(NONTYPE(&F1::m4), &f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+  }
+
+  {
+    F1 const f1;
+
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int() const>, NONTYPE_T(&F1::m1), F1 const*>));
+    BOOST_TEST_TRAIT_FALSE(
+        (std::is_constructible<compat::function_ref<int(int) const>, NONTYPE_T(&F1::m2), F1 const*>));
+
+    compat::function_ref<int(int, int) const> fn3(NONTYPE(&F1::m3), &f1);
+    BOOST_TEST_EQ(fn3(2, 3), 123);
+
+    compat::function_ref<int(int, int, int) const> fn4(NONTYPE(&F1::m4), &f1);
+    BOOST_TEST_EQ(fn4(2, 3, 4), 1234);
+  }
+
+  return boost::report_errors();
+}
--- a/test/function_ref_obj_noexcept_test.cpp
+++ b/test/function_ref_obj_noexcept_test.cpp
@@ -0,0 +1,228 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config/pragma_message.hpp>
+
+#if !defined(__cpp_noexcept_function_type)
+
+BOOST_PRAGMA_MESSAGE("Test skipped, __cpp_noexcept_function_type is not defined")
+int main() {}
+
+#else
+
+#include <boost/compat/function_ref.hpp>
+#include <boost/config.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+struct F1 {
+  int operator()() { return -1; }
+
+  int operator()(int x1) noexcept { return x1; }
+
+  int operator()(int x1, int x2) const { return 10 * x1 + x2; }
+
+  int operator()(int x1, int x2, int x3) const noexcept { return 100 * x1 + 10 * x2 + x3; }
+};
+
+struct F2 {
+  int operator()(int x1, int x2) & { return 100 * x1 + 10 * x2 + 1; }
+  int operator()(int x1, int x2) const& { return 100 * x1 + 10 * x2 + 2; }
+  int operator()(int x1, int x2) && { return 100 * x1 + 10 * x2 + 3; }
+  int operator()(int x1, int x2) const&& { return 100 * x1 + 10 * x2 + 4; }
+};
+
+struct X {
+  int v = 0;
+
+  X() = default;
+  X(int v_) noexcept : v{v_} {}
+};
+
+struct Y {
+  int v = 0;
+
+  Y() = default;
+  explicit Y(int v_) : v{v_} {}
+};
+
+struct Z {
+  int v = 0;
+
+  Z() = default;
+  Z(int v_) : v{v_} {}
+};
+
+namespace compat = boost::compat;
+
+int main() {
+  {
+    F1 f1;
+    {
+      using S1 = int() noexcept;
+      using S2 = int(int) noexcept;
+      using S3 = int(int, int) noexcept;
+      using S4 = int(int, int, int) noexcept;
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&&>));
+
+      compat::function_ref<S2> fv2(f1);
+
+      BOOST_TEST_EQ(fv2(1), 1);
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&&>));
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1 const&&>));
+
+      compat::function_ref<S4> fv4(f1);
+
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&&>));
+    }
+    {
+      using S1 = int() const noexcept;
+      using S2 = int(int) const noexcept;
+      using S3 = int(int, int) const noexcept;
+      using S4 = int(int, int, int) const noexcept;
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&&>));
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&&>));
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S3>, F1 const&&>));
+
+      compat::function_ref<S4> fv4(f1);
+
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&&>));
+    }
+
+    {
+      using S2 = int(int) noexcept;
+      using S4 = int(int, int, int) noexcept;
+
+      auto& fref = f1;
+
+      compat::function_ref<S2> fv2(fref);
+      BOOST_TEST_EQ(fv2(1), 1);
+
+      auto const& cfref = f1;
+      compat::function_ref<S4> fv4(cfref);
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+    }
+
+    {
+      using S4 = int(int, int, int) const noexcept;
+
+      auto const& cfref = f1;
+      compat::function_ref<S4> fv4(cfref);
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+    }
+  }
+
+  {
+    using S1 = int(int, int) noexcept;
+    using S2 = int(int, int) const noexcept;
+
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F2>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F2&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F2&&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F2 const>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F2 const&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F2 const&&>));
+
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F2>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F2&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F2&&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F2 const>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F2 const&>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F2 const&&>));
+  }
+
+  // invoke_r
+  {
+    F1 f;
+
+    compat::function_ref<X(int, int, int) noexcept> fv1(f);
+    BOOST_TEST_EQ(fv1(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int) noexcept>, F1>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Z(int, int, int) noexcept>, F1>));
+
+    compat::function_ref<X(int, int, int) const noexcept> fv2(f);
+    BOOST_TEST_EQ(fv2(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int) const noexcept>, F1>));
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Z(int, int, int) const noexcept>, F1>));
+
+    compat::function_ref<void(int, int, int) noexcept> fv3(f);
+    fv3(1, 2, 3);
+
+    compat::function_ref<void(int, int, int) const noexcept> fv4(f);
+    fv4(1, 2, 3);
+  }
+
+  // copy construct, copy assign
+  {
+    F1 f;
+
+    auto id = [](int x) noexcept { return x + 7331; };
+
+    compat::function_ref<int(int) noexcept> fv(f);
+    compat::function_ref<int(int) noexcept> fv2(fv);
+    BOOST_TEST_EQ(fv(12), fv2(12));
+
+    fv2 = compat::function_ref<int(int) noexcept>(id);
+    BOOST_TEST_EQ(fv2(1), 7332);
+
+    auto add = [](int x, int y, int z) noexcept { return x + y + z; };
+    compat::function_ref<int(int, int, int) const noexcept> cfv(f);
+    compat::function_ref<int(int, int, int) const noexcept> cfv2(cfv);
+    BOOST_TEST_EQ(cfv(1, 2, 3), cfv2(1, 2, 3));
+
+    cfv2 = compat::function_ref<int(int, int, int) const noexcept>(add);
+    BOOST_TEST_EQ(cfv2(1, 2, 3), 6);
+  }
+
+  return boost::report_errors();
+}
+
+#endif
--- a/test/function_ref_obj_test.cpp
+++ b/test/function_ref_obj_test.cpp
@@ -0,0 +1,260 @@
+// Copyright 2024 Christian Mazakas
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/function_ref.hpp>
+#include <boost/config.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+struct F1 {
+  int operator()() { return -1; }
+
+  int operator()(int x1) noexcept { return x1; }
+
+  int operator()(int x1, int x2) const { return 10 * x1 + x2; }
+
+  int operator()(int x1, int x2, int x3) const noexcept { return 100 * x1 + 10 * x2 + x3; }
+};
+
+struct F2 {
+  int operator()(int x1, int x2) & { return 100 * x1 + 10 * x2 + 1; }
+  int operator()(int x1, int x2) const& { return 100 * x1 + 10 * x2 + 2; }
+  int operator()(int x1, int x2) && { return 100 * x1 + 10 * x2 + 3; }
+  int operator()(int x1, int x2) const&& { return 100 * x1 + 10 * x2 + 4; }
+};
+
+struct X {
+  int v = 0;
+
+  X() = default;
+  X(int v_) noexcept : v{v_} {}
+};
+
+struct Y {
+  int v = 0;
+
+  Y() = default;
+  explicit Y(int v_) : v{v_} {}
+};
+
+struct Z {
+  int v = 0;
+
+  Z() = default;
+  Z(int v_) : v{v_} {}
+};
+
+namespace compat = boost::compat;
+
+int main() {
+  {
+    F1 f;
+    {
+      using S1 = int();
+      using S2 = int(int);
+      using S3 = int(int, int);
+      using S4 = int(int, int, int);
+
+      compat::function_ref<S1> fv1(f);
+
+      BOOST_TEST_EQ(fv1(), -1);
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&&>));
+
+      compat::function_ref<S2> fv2(f);
+      int x = 1;
+      BOOST_TEST_EQ(fv2(x), 1);
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&>));
+
+      compat::function_ref<S3> fv3(f);
+
+      BOOST_TEST_EQ(fv3(1, 2), 12);
+
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1&&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1 const>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1 const&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1 const&&>));
+
+      compat::function_ref<S4> fv4(f);
+
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&&>));
+    }
+
+    {
+      using S1 = int() const;
+      using S2 = int(int) const;
+      using S3 = int(int, int) const;
+      using S4 = int(int, int, int) const;
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S1>, F1 const&&>));
+
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1&&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&>));
+      BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<S2>, F1 const&&>));
+
+      compat::function_ref<S3> fv3(f);
+
+      BOOST_TEST_EQ(fv3(1, 2), 12);
+
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1&&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1 const>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1 const&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S3>, F1 const&&>));
+
+      compat::function_ref<S4> fv4(f);
+
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1&&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&>));
+      BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<S4>, F1 const&&>));
+    }
+
+    {
+      using S1 = int();
+      using S2 = int(int);
+
+      auto& fref = f;
+
+      compat::function_ref<S1> fv1(fref);
+      BOOST_TEST_EQ(fv1(), -1);
+
+      compat::function_ref<S2> fv2(fref);
+      BOOST_TEST_EQ(fv2(1), 1);
+    }
+
+    {
+      using S1 = int();
+      using S2 = int(int);
+
+      compat::function_ref<S1> fv1(std::move(f));
+      BOOST_TEST_EQ(fv1(), -1);
+
+      compat::function_ref<S2> fv2(std::move(f));
+      BOOST_TEST_EQ(fv2(1), 1);
+    }
+
+    {
+      using S3 = int(int, int) const;
+      using S4 = int(int, int, int) const;
+
+      auto const& fref = f;
+
+      compat::function_ref<S3> fv3(fref);
+      BOOST_TEST_EQ(fv3(1, 2), 12);
+
+      compat::function_ref<S4> fv4(fref);
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+    }
+
+    {
+      using S3 = int(int, int) const;
+      using S4 = int(int, int, int) const;
+
+      auto const&& fref = std::move(f);
+
+      compat::function_ref<S3> fv3(fref);
+      BOOST_TEST_EQ(fv3(1, 2), 12);
+
+      compat::function_ref<S4> fv4(fref);
+      BOOST_TEST_EQ(fv4(1, 2, 3), 123);
+    }
+  }
+
+  {
+    F2 g;
+    {
+      compat::function_ref<int(int, int)> fv1(g);
+      BOOST_TEST_EQ(fv1(3, 2), 321);
+
+      auto& gref = g;
+      compat::function_ref<int(int, int)> rfv1(gref);
+      BOOST_TEST_EQ(rfv1(3, 2), 321);
+
+      compat::function_ref<int(int, int)> fv2(std::move(g));
+      BOOST_TEST_EQ(fv2(3, 2), 321);
+
+      compat::function_ref<int(int, int) const> fv3(g);
+      BOOST_TEST_EQ(fv3(3, 2), 322);
+
+      auto const& gcref = g;
+      compat::function_ref<int(int, int) const> crfv3(gcref);
+      BOOST_TEST_EQ(fv3(3, 2), 322);
+
+      compat::function_ref<int(int, int) const> fv4(std::move(g));
+      BOOST_TEST_EQ(fv4(3, 2), 322);
+    }
+  }
+
+  // invoke_r
+  {
+    F1 f;
+
+    compat::function_ref<X(int, int, int)> fv1(f);
+    BOOST_TEST_EQ(fv1(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int)>, F1>));
+    BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<Z(int, int, int)>, F1>));
+
+    compat::function_ref<X(int, int, int) const> fv2(f);
+    BOOST_TEST_EQ(fv2(1, 2, 3).v, 123);
+    BOOST_TEST_TRAIT_FALSE((std::is_constructible<compat::function_ref<Y(int, int, int) const>, F1>));
+    BOOST_TEST_TRAIT_TRUE((std::is_constructible<compat::function_ref<Z(int, int, int) const>, F1>));
+
+    compat::function_ref<void(int, int, int)> fv3(f);
+    fv3(1, 2, 3);
+
+    compat::function_ref<void(int, int, int) const> fv4(f);
+    fv4(1, 2, 3);
+  }
+
+  // copy construct, copy assign
+  {
+    F1 f;
+
+    auto id = [] { return 7331; };
+
+    compat::function_ref<int()> fv(f);
+    compat::function_ref<int()> fv2(fv);
+    BOOST_TEST_EQ(fv(), fv2());
+
+    fv2 = compat::function_ref<int()>(id);
+    BOOST_TEST_EQ(fv2(), 7331);
+
+    auto add = [](int x, int y) { return x + y; };
+    compat::function_ref<int(int, int) const> cfv(f);
+    compat::function_ref<int(int, int) const> cfv2(cfv);
+    BOOST_TEST_EQ(cfv(1, 2), cfv2(1, 2));
+
+    cfv2 = compat::function_ref<int(int, int) const>(add);
+    BOOST_TEST_EQ(cfv2(1, 2), 3);
+  }
+
+  return boost::report_errors();
+}
--- a/test/integer_sequence_test.cpp
+++ b/test/integer_sequence_test.cpp
@@ -0,0 +1,55 @@
+// Copyright 2015 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/integer_sequence.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <type_traits>
+#include <cstddef>
+
+int main()
+{
+    using boost::compat::integer_sequence;
+    using boost::compat::make_integer_sequence;
+    using boost::compat::index_sequence;
+    using boost::compat::make_index_sequence;
+    using boost::compat::index_sequence_for;
+
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<int, 0>, integer_sequence<int>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<int, 1>, integer_sequence<int, 0>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<int, 2>, integer_sequence<int, 0, 1>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<int, 3>, integer_sequence<int, 0, 1, 2>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<int, 4>, integer_sequence<int, 0, 1, 2, 3>);
+
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<char, 0>, integer_sequence<char>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<char, 1>, integer_sequence<char, 0>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<char, 2>, integer_sequence<char, 0, 1>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<char, 3>, integer_sequence<char, 0, 1, 2>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<char, 4>, integer_sequence<char, 0, 1, 2, 3>);
+
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<std::size_t, 0>, integer_sequence<std::size_t>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<std::size_t, 1>, integer_sequence<std::size_t, 0>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<std::size_t, 2>, integer_sequence<std::size_t, 0, 1>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<std::size_t, 3>, integer_sequence<std::size_t, 0, 1, 2>);
+    BOOST_TEST_TRAIT_SAME(make_integer_sequence<std::size_t, 4>, integer_sequence<std::size_t, 0, 1, 2, 3>);
+
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<0>, integer_sequence<std::size_t>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<1>, integer_sequence<std::size_t, 0>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<2>, integer_sequence<std::size_t, 0, 1>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<3>, integer_sequence<std::size_t, 0, 1, 2>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<4>, integer_sequence<std::size_t, 0, 1, 2, 3>);
+
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<0>, index_sequence<>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<1>, index_sequence<0>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<2>, index_sequence<0, 1>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<3>, index_sequence<0, 1, 2>);
+    BOOST_TEST_TRAIT_SAME(make_index_sequence<4>, index_sequence<0, 1, 2, 3>);
+
+    BOOST_TEST_TRAIT_SAME(index_sequence_for<>, index_sequence<>);
+    BOOST_TEST_TRAIT_SAME(index_sequence_for<void>, index_sequence<0>);
+    BOOST_TEST_TRAIT_SAME(index_sequence_for<void, void>, index_sequence<0, 1>);
+    BOOST_TEST_TRAIT_SAME(index_sequence_for<void, void, void>, index_sequence<0, 1, 2>);
+    BOOST_TEST_TRAIT_SAME(index_sequence_for<void, void, void, void>, index_sequence<0, 1, 2, 3>);
+
+    return boost::report_errors();
+}
--- a/test/invoke_fn_constexpr_test.cpp
+++ b/test/invoke_fn_constexpr_test.cpp
@@ -0,0 +1,40 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+constexpr int f0()
+{
+    return -1;
+}
+
+constexpr int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+constexpr int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+constexpr int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::invoke( f0 ), -1 );
+    BOOST_TEST_EQ( boost::compat::invoke( f1, 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::invoke( f2, 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::invoke( f3, 1, 2, 3 ), 123 );
+}
--- a/test/invoke_fn_noexcept_test.cpp
+++ b/test/invoke_fn_noexcept_test.cpp
@@ -0,0 +1,47 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config/pragma_message.hpp>
+
+#if !defined(__cpp_noexcept_function_type)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, __cpp_noexcept_function_type is not defined" )
+int main() {}
+
+#else
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+int f0()
+{
+    return -1;
+}
+
+int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke( f0 ) ), false );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke( f1, 1 ) ), true );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke( f2, 1, 2 ) ), false );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke( f3, 1, 2, 3 ) ), true );
+
+    return boost::report_errors();
+}
+
+#endif
--- a/test/invoke_fn_test.cpp
+++ b/test/invoke_fn_test.cpp
@@ -0,0 +1,40 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+int f0()
+{
+    return -1;
+}
+
+int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::invoke( f0 ), -1 );
+    BOOST_TEST_EQ( boost::compat::invoke( f1, 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::invoke( f2, 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::invoke( f3, 1, 2, 3 ), 123 );
+
+    return boost::report_errors();
+}
--- a/test/invoke_md_constexpr_test.cpp
+++ b/test/invoke_md_constexpr_test.cpp
@@ -0,0 +1,42 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, X() ), -1 );
+
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &x ), -1 );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, >= 1920 && BOOST_MSVC < 1950)
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, Y() ), -1 );
+
+        constexpr Y y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &y ), -1 );
+    }
+#endif
+}
--- a/test/invoke_md_noexcept_test.cpp
+++ b/test/invoke_md_noexcept_test.cpp
@@ -0,0 +1,60 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, X() ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, Y() ) ), true );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, &x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, std::ref(x) ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, std::cref(x) ) ), true );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, &y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, std::ref(y) ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, std::cref(y) ) ), true );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, &x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, std::ref(x) ) ), true );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, &y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::m, std::ref(y) ) ), true );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_md_test.cpp
+++ b/test/invoke_md_test.cpp
@@ -0,0 +1,105 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, X() ), -1 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, Y() ), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, x ), -1 );
+        boost::compat::invoke( &X::m, x ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, x ), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &x ), -1 );
+        boost::compat::invoke( &X::m, &x ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &x ), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::ref(x) ), -1 );
+        boost::compat::invoke( &X::m, std::ref(x) ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::ref(x) ), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::cref(x) ), -1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, y ), -1 );
+        boost::compat::invoke( &X::m, y ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, y ), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &y ), -1 );
+        boost::compat::invoke( &X::m, &y ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &y ), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::ref(y) ), -1 );
+        boost::compat::invoke( &X::m, std::ref(y) ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::ref(y) ), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::cref(y) ), -1 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::ref(x) ), -1 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::m, std::ref(y) ), -1 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_mfn_constexpr_test.cpp
+++ b/test/invoke_mfn_constexpr_test.cpp
@@ -0,0 +1,88 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    constexpr int f0() const
+    {
+        return -1;
+    }
+
+    constexpr int f1( int x1 ) const noexcept
+    {
+        return x1;
+    }
+
+    constexpr int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, X(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, Y() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, Y(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, &x, 1, 2, 3 ), 123 );
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+    {
+        constexpr Y y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, &y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, &y, 1, 2, 3 ), 123 );
+    }
+#endif
+}
--- a/test/invoke_mfn_noexcept_test.cpp
+++ b/test/invoke_mfn_noexcept_test.cpp
@@ -0,0 +1,134 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config/pragma_message.hpp>
+
+#if !defined(__cpp_noexcept_function_type)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, __cpp_noexcept_function_type is not defined" )
+int main() {}
+
+#else
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, X() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, X(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, X(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, X(), 1, 2, 3 ) ), true );
+    }
+
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, Y() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, Y(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, Y(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, Y(), 1, 2, 3 ) ), true );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, x ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, x, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, &x ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, &x, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, &x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, &x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, std::ref(x) ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, std::ref(x), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, std::ref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, std::ref(x), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, std::cref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, std::cref(x), 1, 2, 3 ) ), true );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, y ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, y, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, &y ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, &y, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, &y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, &y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f0, std::ref(y) ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f1, std::ref(y), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, std::ref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, std::ref(y), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, std::cref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, std::cref(y), 1, 2, 3 ) ), true );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, &x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, &x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, std::ref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, std::ref(x), 1, 2, 3 ) ), true );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, &y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, &y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f2, std::ref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( &X::f3, std::ref(y), 1, 2, 3 ) ), true );
+    }
+
+    return boost::report_errors();
+}
+
+#endif
--- a/test/invoke_mfn_test.cpp
+++ b/test/invoke_mfn_test.cpp
@@ -0,0 +1,127 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, X(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, Y() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, Y(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, std::ref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, std::cref(x), 1, 2, 3 ), 123 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, &y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, &y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f0, std::ref(y) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f1, std::ref(y), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, std::ref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, std::ref(y), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, std::cref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, std::cref(y), 1, 2, 3 ), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, std::ref(x), 1, 2, 3 ), 123 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, &y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f2, std::ref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( &X::f3, std::ref(y), 1, 2, 3 ), 123 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_obj_constexpr_test.cpp
+++ b/test/invoke_obj_constexpr_test.cpp
@@ -0,0 +1,50 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+
+#define STATIC_ASSERT(...) static_assert(__VA_ARGS__, #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct F
+{
+    constexpr int operator()() const
+    {
+        return -1;
+    }
+
+    constexpr int operator()( int x1 ) const noexcept
+    {
+        return x1;
+    }
+
+    constexpr int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( F() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( F(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( F(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( F(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        constexpr F f = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( f ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1, 2, 3 ), 123 );
+    }
+}
--- a/test/invoke_obj_noexcept_test.cpp
+++ b/test/invoke_obj_noexcept_test.cpp
@@ -0,0 +1,57 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+struct F
+{
+    int operator()()
+    {
+        return -1;
+    }
+
+    int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( F() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( F(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( F(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( F(), 1, 2, 3 ) ), true );
+    }
+
+    {
+        F f = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( f ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( f, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( f, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( f, 1, 2, 3 ) ), true );
+    }
+
+    {
+        F const f = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( f, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke( f, 1, 2, 3 ) ), true );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_obj_test.cpp
+++ b/test/invoke_obj_test.cpp
@@ -0,0 +1,57 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+struct F
+{
+    int operator()()
+    {
+        return -1;
+    }
+
+    int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke( F() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( F(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( F(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( F(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        F f;
+
+        BOOST_TEST_EQ( boost::compat::invoke( f ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1, 2, 3 ), 123 );
+    }
+
+    {
+        F const f = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke( f, 1, 2, 3 ), 123 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_r_fn_constexpr_test.cpp
+++ b/test/invoke_r_fn_constexpr_test.cpp
@@ -0,0 +1,50 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/config.hpp>
+
+#define STATIC_ASSERT(...) static_assert((__VA_ARGS__), #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+constexpr int f0()
+{
+    return -1;
+}
+
+constexpr int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+constexpr int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+constexpr int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f0 ), -1 );
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f1, 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f2, 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f3, 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+    STATIC_ASSERT( boost::compat::invoke_r<void>( f0 ), true );
+    STATIC_ASSERT( boost::compat::invoke_r<void>( f1, 1 ), true );
+    STATIC_ASSERT( boost::compat::invoke_r<void>( f2, 1, 2 ), true );
+    STATIC_ASSERT( boost::compat::invoke_r<void>( f3, 1, 2, 3 ), true );
+
+#endif
+}
--- a/test/invoke_r_fn_noexcept_test.cpp
+++ b/test/invoke_r_fn_noexcept_test.cpp
@@ -0,0 +1,52 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config/pragma_message.hpp>
+
+#if !defined(__cpp_noexcept_function_type)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, __cpp_noexcept_function_type is not defined" )
+int main() {}
+
+#else
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+int f0()
+{
+    return -1;
+}
+
+int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f0 ) ), false );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f1, 1 ) ), true );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f2, 1, 2 ) ), false );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f3, 1, 2, 3 ) ), true );
+
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f0 ) ), false );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f1, 1 ) ), true );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f2, 1, 2 ) ), false );
+    BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f3, 1, 2, 3 ) ), true );
+
+    return boost::report_errors();
+}
+
+#endif
--- a/test/invoke_r_fn_test.cpp
+++ b/test/invoke_r_fn_test.cpp
@@ -0,0 +1,45 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+int f0()
+{
+    return -1;
+}
+
+int f1( int x1 ) noexcept
+{
+    return x1;
+}
+
+int f2( int x1, int x2 )
+{
+    return 10*x1+x2;
+}
+
+int f3( int x1, int x2, int x3 ) noexcept
+{
+    return 100*x1 + 10*x2 + x3;
+}
+
+int main()
+{
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f0 ), -1 );
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f1, 1 ), 1 );
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f2, 1, 2 ), 12 );
+    BOOST_TEST_EQ( boost::compat::invoke_r<long>( f3, 1, 2, 3 ), 123 );
+
+    boost::compat::invoke_r<void>( f0 );
+    boost::compat::invoke_r<void>( f1, 1 );
+    boost::compat::invoke_r<void>( f2, 1, 2 );
+    boost::compat::invoke_r<void>( f3, 1, 2, 3 );
+
+    return boost::report_errors();
+}
--- a/test/invoke_r_md_constexpr_test.cpp
+++ b/test/invoke_r_md_constexpr_test.cpp
@@ -0,0 +1,56 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+#define STATIC_ASSERT(...) static_assert((__VA_ARGS__), #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, &x ), -1 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::m, X() ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::m, x ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::m, &x ), true );
+
+#endif
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, >= 1920 && BOOST_MSVC < 1950)
+    {
+        constexpr Y y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, Y() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, &y ), -1 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::m, Y() ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::m, y ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::m, &y ), true );
+
+#endif
+    }
+#endif
+}
--- a/test/invoke_r_md_noexcept_test.cpp
+++ b/test/invoke_r_md_noexcept_test.cpp
@@ -0,0 +1,99 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, X() ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, Y() ) ), true );
+    }
+
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, X() ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, Y() ) ), true );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, &x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, std::ref(x) ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, std::cref(x) ) ), true );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, &x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, std::ref(x) ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, std::cref(x) ) ), true );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, &y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, std::ref(y) ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, std::cref(y) ) ), true );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, &y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, std::ref(y) ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, std::cref(y) ) ), true );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, &x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, std::ref(x) ) ), true );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, &x ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, std::ref(x) ) ), true );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, &y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::m, std::ref(y) ) ), true );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, &y ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::m, std::ref(y) ) ), true );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_r_md_test.cpp
+++ b/test/invoke_r_md_test.cpp
@@ -0,0 +1,131 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, X() ), -1 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, Y() ), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, x ), -1 );
+        boost::compat::invoke_r<int&>( &X::m, x ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, x ), +1 );
+        boost::compat::invoke_r<void>( &X::m, x );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, &x ), -1 );
+        boost::compat::invoke_r<int&>( &X::m, &x ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, &x ), +1 );
+        boost::compat::invoke_r<void>( &X::m, &x );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, std::ref(x) ), -1 );
+        boost::compat::invoke_r<int&>( &X::m, std::ref(x) ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, std::ref(x) ), +1 );
+        boost::compat::invoke_r<void>( &X::m, std::ref(x) );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, std::cref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, std::cref(x) ), -1 );
+        boost::compat::invoke_r<void>( &X::m, std::cref(x) );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, y ), -1 );
+        boost::compat::invoke_r<int&>( &X::m, y ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, y ), +1 );
+        boost::compat::invoke_r<void>( &X::m, y );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, &y ), -1 );
+        boost::compat::invoke_r<int&>( &X::m, &y ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, &y ), +1 );
+        boost::compat::invoke_r<void>( &X::m, &y );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, std::ref(y) ), -1 );
+        boost::compat::invoke_r<int&>( &X::m, std::ref(y) ) = +1;
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, std::ref(y) ), +1 );
+        boost::compat::invoke_r<void>( &X::m, std::ref(y) );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, std::cref(y) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, std::cref(y) ), -1 );
+        boost::compat::invoke_r<void>( &X::m, std::cref(y) );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, x ), -1 );
+        boost::compat::invoke_r<void>( &X::m, x );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, &x ), -1 );
+        boost::compat::invoke_r<void>( &X::m, &x );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, std::ref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, std::ref(x) ), -1 );
+        boost::compat::invoke_r<void>( &X::m, std::ref(x) );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, y ), -1 );
+        boost::compat::invoke_r<void>( &X::m, y );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, &y ), -1 );
+        boost::compat::invoke_r<void>( &X::m, &y );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<int const&>( &X::m, std::ref(y) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::m, std::ref(y) ), -1 );
+        boost::compat::invoke_r<void>( &X::m, std::ref(y) );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_r_mfn_constexpr_test.cpp
+++ b/test/invoke_r_mfn_constexpr_test.cpp
@@ -0,0 +1,134 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+#define STATIC_ASSERT(...) static_assert((__VA_ARGS__), #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct X
+{
+    constexpr int f0() const
+    {
+        return -1;
+    }
+
+    constexpr int f1( int x1 ) const noexcept
+    {
+        return x1;
+    }
+
+    constexpr int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, X(), 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f0, X() ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f1, X(), 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f2, X(), 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f3, X(), 1, 2, 3 ), true );
+
+#endif
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, Y() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, Y(), 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f0, Y() ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f1, Y(), 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f2, Y(), 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f3, Y(), 1, 2, 3 ), true );
+
+#endif
+    }
+
+    {
+        constexpr X x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, &x, 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f0, x ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f1, x, 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f2, x, 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f3, x, 1, 2, 3 ), true );
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f0, &x ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f1, &x, 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f2, &x, 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f3, &x, 1, 2, 3 ), true );
+
+#endif
+    }
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+    {
+        constexpr Y y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, &y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, &y, 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f0, y ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f1, y, 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f2, y, 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f3, y, 1, 2, 3 ), true );
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f0, &y ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f1, &y, 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f2, &y, 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( &X::f3, &y, 1, 2, 3 ), true );
+
+#endif
+    }
+#endif
+}
--- a/test/invoke_r_mfn_noexcept_test.cpp
+++ b/test/invoke_r_mfn_noexcept_test.cpp
@@ -0,0 +1,214 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/config/pragma_message.hpp>
+
+#if !defined(__cpp_noexcept_function_type)
+
+BOOST_PRAGMA_MESSAGE( "Test skipped, __cpp_noexcept_function_type is not defined" )
+int main() {}
+
+#else
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, X() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, X(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, X(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, X(), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, X() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, X(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, X(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, X(), 1, 2, 3 ) ), true );
+    }
+
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, Y() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, Y(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, Y(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, Y(), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, Y() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, Y(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, Y(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, Y(), 1, 2, 3 ) ), true );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, x ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, x, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, &x ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, &x, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, &x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, &x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, std::ref(x) ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, std::ref(x), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, std::ref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, std::ref(x), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, std::cref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, std::cref(x), 1, 2, 3 ) ), true );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, x ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, x, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, &x ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, &x, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, &x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, &x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, std::ref(x) ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, std::ref(x), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, std::ref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, std::ref(x), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, std::cref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, std::cref(x), 1, 2, 3 ) ), true );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, y ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, y, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, &y ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, &y, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, &y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, &y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f0, std::ref(y) ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f1, std::ref(y), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, std::ref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, std::ref(y), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, std::cref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, std::cref(y), 1, 2, 3 ) ), true );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, y ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, y, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, &y ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, &y, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, &y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, &y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f0, std::ref(y) ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f1, std::ref(y), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, std::ref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, std::ref(y), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, std::cref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, std::cref(y), 1, 2, 3 ) ), true );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, &x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, &x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, std::ref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, std::ref(x), 1, 2, 3 ) ), true );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, &x, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, &x, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, std::ref(x), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, std::ref(x), 1, 2, 3 ) ), true );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, &y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, &y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f2, std::ref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( &X::f3, std::ref(y), 1, 2, 3 ) ), true );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, &y, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, &y, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f2, std::ref(y), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( &X::f3, std::ref(y), 1, 2, 3 ) ), true );
+    }
+
+    return boost::report_errors();
+}
+
+#endif
--- a/test/invoke_r_mfn_test.cpp
+++ b/test/invoke_r_mfn_test.cpp
@@ -0,0 +1,211 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, X(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, Y() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, Y(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, std::ref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, std::cref(x), 1, 2, 3 ), 123 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, &y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, &y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f0, std::ref(y) ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f1, std::ref(y), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, std::ref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, std::ref(y), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, std::cref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, std::cref(y), 1, 2, 3 ), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, std::ref(x), 1, 2, 3 ), 123 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, &y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f2, std::ref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( &X::f3, std::ref(y), 1, 2, 3 ), 123 );
+    }
+
+    {
+        boost::compat::invoke_r<void>( &X::f0, X() );
+        boost::compat::invoke_r<void>( &X::f1, X(), 1 );
+        boost::compat::invoke_r<void>( &X::f2, X(), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, X(), 1, 2, 3 );
+    }
+
+    {
+        boost::compat::invoke_r<void>( &X::f0, Y() );
+        boost::compat::invoke_r<void>( &X::f1, Y(), 1 );
+        boost::compat::invoke_r<void>( &X::f2, Y(), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, Y(), 1, 2, 3 );
+    }
+
+    {
+        X x;
+
+        boost::compat::invoke_r<void>( &X::f0, x );
+        boost::compat::invoke_r<void>( &X::f1, x, 1 );
+        boost::compat::invoke_r<void>( &X::f2, x, 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, x, 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f0, &x );
+        boost::compat::invoke_r<void>( &X::f1, &x, 1 );
+        boost::compat::invoke_r<void>( &X::f2, &x, 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, &x, 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f0, std::ref(x) );
+        boost::compat::invoke_r<void>( &X::f1, std::ref(x), 1 );
+        boost::compat::invoke_r<void>( &X::f2, std::ref(x), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, std::ref(x), 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f2, std::cref(x), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, std::cref(x), 1, 2, 3 );
+    }
+
+    {
+        Y y;
+
+        boost::compat::invoke_r<void>( &X::f0, y );
+        boost::compat::invoke_r<void>( &X::f1, y, 1 );
+        boost::compat::invoke_r<void>( &X::f2, y, 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, y, 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f0, &y );
+        boost::compat::invoke_r<void>( &X::f1, &y, 1 );
+        boost::compat::invoke_r<void>( &X::f2, &y, 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, &y, 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f0, std::ref(y) );
+        boost::compat::invoke_r<void>( &X::f1, std::ref(y), 1 );
+        boost::compat::invoke_r<void>( &X::f2, std::ref(y), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, std::ref(y), 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f2, std::cref(y), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, std::cref(y), 1, 2, 3 );
+    }
+
+    {
+        X const x = {};
+
+        boost::compat::invoke_r<void>( &X::f2, x, 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, x, 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f2, &x, 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, &x, 1, 2, 3 );
+
+        boost::compat::invoke_r<void>( &X::f2, std::ref(x), 1, 2 );
+        boost::compat::invoke_r<void>( &X::f3, std::ref(x), 1, 2, 3 );
+    }
+
+    {
+        Y const y = {};
+
+        boost::compat::invoke_r<long>( &X::f2, y, 1, 2 );
+        boost::compat::invoke_r<long>( &X::f3, y, 1, 2, 3 );
+
+        boost::compat::invoke_r<long>( &X::f2, &y, 1, 2 );
+        boost::compat::invoke_r<long>( &X::f3, &y, 1, 2, 3 );
+
+        boost::compat::invoke_r<long>( &X::f2, std::ref(y), 1, 2 );
+        boost::compat::invoke_r<long>( &X::f3, std::ref(y), 1, 2, 3 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_r_obj_constexpr_test.cpp
+++ b/test/invoke_r_obj_constexpr_test.cpp
@@ -0,0 +1,68 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+
+#define STATIC_ASSERT(...) static_assert((__VA_ARGS__), #__VA_ARGS__)
+#define BOOST_TEST_EQ(x, y) STATIC_ASSERT((x) == (y))
+
+struct F
+{
+    constexpr int operator()() const
+    {
+        return -1;
+    }
+
+    constexpr int operator()( int x1 ) const noexcept
+    {
+        return x1;
+    }
+
+    constexpr int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    constexpr int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( F() ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( F(), 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( F(), 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( F(), 1, 2, 3 ), true );
+
+#endif
+    }
+
+    {
+        constexpr F f = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2, 3 ), 123 );
+
+#if !defined(BOOST_NO_CXX14_CONSTEXPR)
+
+        STATIC_ASSERT( boost::compat::invoke_r<void>( f ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( f, 1 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( f, 1, 2 ), true );
+        STATIC_ASSERT( boost::compat::invoke_r<void>( f, 1, 2, 3 ), true );
+
+#endif
+    }
+}
--- a/test/invoke_r_obj_noexcept_test.cpp
+++ b/test/invoke_r_obj_noexcept_test.cpp
@@ -0,0 +1,70 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+struct F
+{
+    int operator()()
+    {
+        return -1;
+    }
+
+    int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( F() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( F(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( F(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( F(), 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( F() ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( F(), 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( F(), 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( F(), 1, 2, 3 ) ), true );
+    }
+
+    {
+        F f = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f, 1 ) ), true );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f, 1, 2, 3 ) ), true );
+    }
+
+    {
+        F const f = {};
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<long>( f, 1, 2, 3 ) ), true );
+
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f, 1, 2 ) ), false );
+        BOOST_TEST_EQ( noexcept( boost::compat::invoke_r<void>( f, 1, 2, 3 ) ), true );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_r_obj_test.cpp
+++ b/test/invoke_r_obj_test.cpp
@@ -0,0 +1,80 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+struct F
+{
+    int operator()()
+    {
+        return -1;
+    }
+
+    int operator()( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int operator()( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F() ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( F(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        F f;
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f ), -1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2, 3 ), 123 );
+    }
+
+    {
+        F const f = {};
+
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::invoke_r<long>( f, 1, 2, 3 ), 123 );
+    }
+
+    {
+        boost::compat::invoke_r<void>( F() );
+        boost::compat::invoke_r<void>( F(), 1 );
+        boost::compat::invoke_r<void>( F(), 1, 2 );
+        boost::compat::invoke_r<void>( F(), 1, 2, 3 );
+    }
+
+    {
+        F f;
+
+        boost::compat::invoke_r<void>( f );
+        boost::compat::invoke_r<void>( f, 1 );
+        boost::compat::invoke_r<void>( f, 1, 2 );
+        boost::compat::invoke_r<void>( f, 1, 2, 3 );
+    }
+
+    {
+        F const f = {};
+
+        boost::compat::invoke_r<void>( f, 1, 2 );
+        boost::compat::invoke_r<void>( f, 1, 2, 3 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/invoke_result_test.cpp
+++ b/test/invoke_result_test.cpp
@@ -0,0 +1,107 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/mp11/utility.hpp>
+
+struct F
+{
+    void operator()()
+    {
+    }
+
+    char operator()( char x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    double operator()( float x1, float x2, float x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct X
+{
+};
+
+int main()
+{
+    using boost::compat::invoke_result_t;
+    using boost::mp11::mp_valid;
+
+    // nonfunction
+
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, int, int, int> ));
+
+    // function reference
+
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<void(&)()>, void );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<char(&)(int), char>, char );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int(&)(int, int), int, int>, int );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<double(&)(double, double, double), float, float, float>, double );
+
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(&)(int), int, int> ));
+
+    // function pointer
+
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<void(*)()>, void );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<char(*)(int), char>, char );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int(*)(int, int), int, int>, int );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<double(*)(double, double, double), float, float, float>, double );
+
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(*)(int), int, int> ));
+
+    // object
+
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<F>, void );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<F, char>, char );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<F, int, int>, int );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<F, float, float, float>, double );
+
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, F, int, int, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, F const> ));
+
+    // member function pointer
+
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<void(X::*)(), X>, void );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<char(X::*)(int), X, char>, char );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int(X::*)(int, int), X, int, int>, int );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<double(X::*)(double, double, double), X, float, float, float>, double );
+
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, char(X::*)(int), X, int, int> ));
+
+    // member data pointer
+
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int X::*, X>, int&& );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int X::*, X const>, int const&& );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int X::*, X&>, int& );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int X::*, X const&>, int const& );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int X::*, X*>, int& );
+    BOOST_TEST_TRAIT_SAME( invoke_result_t<int X::*, X const*>, int const& );
+
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( mp_valid<invoke_result_t, int X::*, X, int> ));
+
+    return boost::report_errors();
+}
--- a/test/is_invocable_r_test.cpp
+++ b/test/is_invocable_r_test.cpp
@@ -0,0 +1,195 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+struct F
+{
+    void operator()()
+    {
+    }
+
+    char operator()( char x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    double operator()( float x1, float x2, float x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct X
+{
+};
+
+int main()
+{
+    using boost::compat::is_invocable_r;
+
+    // nonfunction
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, int, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, int, int, int> ));
+
+    // function reference
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(&)()> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, char(&)(int), char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, double(&)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, void(&)()> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, char(&)(int), char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, double(&)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, void(&)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, char(&)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, double(&)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(&)(int), int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(&)(int), int, int> ));
+
+    // function pointer
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(*)()> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, char(*)(int), char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, double(*)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, void(*)()> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, char(*)(int), char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, double(*)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, void(*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, char(*)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, double(*)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(*)(int), int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(*)(int), int, int> ));
+
+    // object
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, F> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, F, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, F> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, F, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, F> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, F, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, F, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, F, int, int, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, F const> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, F, int, int, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, F const> ));
+
+    // member function pointer
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, double(X::*)(double, double, double), X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, double(X::*)(double, double, double), X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, double(X::*)(double, double, double), X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, char(X::*)(int), X, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, char(X::*)(int), X, int, int> ));
+
+    // member data pointer
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<long, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<void, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int X::*, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int X::*, X const> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int X::*, X&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int X::*, X*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<X, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<int&, int X::*, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<int&, int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<int&, int X::*, X&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<int&, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<int&, int X::*, X*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<int&, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable_r<int&&, int X::*, X> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<long, int X::*, X, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable_r<void, int X::*, X, int> ));
+
+    return boost::report_errors();
+}
--- a/test/is_invocable_test.cpp
+++ b/test/is_invocable_test.cpp
@@ -0,0 +1,105 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+struct F
+{
+    void operator()()
+    {
+    }
+
+    char operator()( char x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    double operator()( float x1, float x2, float x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct X
+{
+};
+
+int main()
+{
+    using boost::compat::is_invocable;
+
+    // nonfunction
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<int, int, int> ));
+
+    // function reference
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<void(&)()> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<char(&)(int), char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<double(&)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(&)(int), int, int> ));
+
+    // function pointer
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<void(*)()> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<char(*)(int), char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<double(*)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(*)(int), int, int> ));
+
+    // object
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<F> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<F, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<F, int, int, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<F const> ));
+
+    // member function pointer
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<double(X::*)(double, double, double), X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<char(X::*)(int), X, int, int> ));
+
+    // member data pointer
+
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_invocable<int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_invocable<int X::*, X, int> ));
+
+    return boost::report_errors();
+}
--- a/test/is_nothrow_invocable_r_test.cpp
+++ b/test/is_nothrow_invocable_r_test.cpp
@@ -0,0 +1,288 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+struct F
+{
+    void operator()()
+    {
+    }
+
+    char operator()( char x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    double operator()( float x1, float x2, float x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct X
+{
+};
+
+struct Y
+{
+    Y( int );
+    Y( double ) noexcept;
+};
+
+int main()
+{
+    using boost::compat::is_nothrow_invocable_r;
+
+    // nonfunction
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int, int, int> ));
+
+    // function reference
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(&)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(&)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, double(&)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(&)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(&)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, double(&)(double, double, double), float, float, float> ));
+
+#if defined(__cpp_noexcept_function_type)
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(&)() noexcept> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, char(&)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int(&)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, double(&)(double, double, double) noexcept, float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, void(&)() noexcept> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, char(&)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int(&)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, double(&)(double, double, double) noexcept, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, void(&)() noexcept> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, char(&)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int(&)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, double(&)(double, double, double) noexcept, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, void(&)() noexcept> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, char(&)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int(&)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double(&)(double, double, double) noexcept, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(&)(int), int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(&)(int), int, int> ));
+
+    // function pointer
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(*)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, double(*)(double, double, double), float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(*)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, double(*)(double, double, double), float, float, float> ));
+
+#if defined(__cpp_noexcept_function_type)
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(*)() noexcept> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, char(*)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int(*)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, double(*)(double, double, double) noexcept, float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, void(*)() noexcept> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, char(*)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int(*)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, double(*)(double, double, double) noexcept, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, void(*)() noexcept> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, char(*)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int(*)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, double(*)(double, double, double) noexcept, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, void(*)() noexcept> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, char(*)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int(*)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double(*)(double, double, double) noexcept, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(*)(int), int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(*)(int), int, int> ));
+
+    // object
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, F> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, F, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, F> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, F, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, F> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, F, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, F> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, F, int, int> ));
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, F, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, F, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, F, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, F, int, int, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, F const> ));
+
+    // member function pointer
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, double(X::*)(double, double, double), X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, double(X::*)(double, double, double), X, float, float, float> ));
+
+#if defined(__cpp_noexcept_function_type)
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(X::*)() noexcept, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, char(X::*)(int) noexcept, X, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int(X::*)(int, int) noexcept, X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, double(X::*)(double, double, double) noexcept, X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, void(X::*)() noexcept, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, char(X::*)(int) noexcept, X, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int(X::*)(int, int) noexcept, X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, double(X::*)(double, double, double) noexcept, X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, void(X::*)() noexcept, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, char(X::*)(int) noexcept, X, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int(X::*)(int, int) noexcept, X, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, double(X::*)(double, double, double) noexcept, X, float, float, float> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, void(X::*)() noexcept, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, char(X::*)(int) noexcept, X, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int(X::*)(int, int) noexcept, X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double(X::*)(double, double, double) noexcept, X, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, char(X::*)(int), X, int, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, char(X::*)(int), X, int, int> ));
+
+    // member data pointer
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<long, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<void, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int X::*, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int X::*, X const> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int X::*, X&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int X::*, X*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<X, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int X::*, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int X::*, X const> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int X::*, X&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int X::*, X*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<Y, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<Y, double X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<int&, int X::*, X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<int&, int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<int&, int X::*, X&> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<int&, int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<int&, int X::*, X*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<int&, int X::*, X const*> ));
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable_r<int&&, int X::*, X> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<long, int X::*, X, int> ));
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable_r<void, int X::*, X, int> ));
+
+    return boost::report_errors();
+}
--- a/test/is_nothrow_invocable_test.cpp
+++ b/test/is_nothrow_invocable_test.cpp
@@ -0,0 +1,143 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/invoke.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+struct F
+{
+    void operator()()
+    {
+    }
+
+    char operator()( char x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int operator()( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    double operator()( float x1, float x2, float x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct X
+{
+};
+
+int main()
+{
+    using boost::compat::is_nothrow_invocable;
+
+    // nonfunction
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int, int, int> ));
+
+    // function reference
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(&)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(&)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int(&)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<double(&)(double, double, double), float, float, float> ));
+
+#if defined(__cpp_noexcept_function_type)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<void(&)() noexcept> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<char(&)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int(&)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<double(&)(double, double, double) noexcept, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(&)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(&)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(&)(int), int, int> ));
+
+    // function pointer
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(*)(int), char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int(*)(int, int), int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<double(*)(double, double, double), float, float, float> ));
+
+#if defined(__cpp_noexcept_function_type)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<void(*)() noexcept> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<char(*)(int) noexcept, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int(*)(int, int) noexcept, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<double(*)(double, double, double) noexcept, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(*)(int), int, int> ));
+
+    // object
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<F> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<F, int, int> ));
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<F, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<F, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<F, int, int, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<F const> ));
+
+    // member function pointer
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(X::*)(), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(X::*)(int), X, char> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int(X::*)(int, int), X, int, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<double(X::*)(double, double, double), X, float, float, float> ));
+
+#if defined(__cpp_noexcept_function_type)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<void(X::*)() noexcept, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<char(X::*)(int) noexcept, X, char> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int(X::*)(int, int) noexcept, X, int, int> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<double(X::*)(double, double, double) noexcept, X, float, float, float> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(X::*)()> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(X::*)(), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<void(X::*)(), X, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(X::*)(int)> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(X::*)(int), int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(X::*)(int), X> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<char(X::*)(int), X, int, int> ));
+
+    // member data pointer
+
+#if !BOOST_WORKAROUND(BOOST_MSVC, < 1910)
+
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int X::*, X> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int X::*, X const> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int X::*, X&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int X::*, X const&> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int X::*, X*> ));
+    BOOST_TEST_TRAIT_TRUE(( is_nothrow_invocable<int X::*, X const*> ));
+
+#endif
+
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int X::*> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int X::*, int> ));
+    BOOST_TEST_TRAIT_FALSE(( is_nothrow_invocable<int X::*, X, int> ));
+
+    return boost::report_errors();
+}
--- a/test/mem_fn_md_test.cpp
+++ b/test/mem_fn_md_test.cpp
@@ -0,0 +1,105 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/mem_fn.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int m = -1;
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( X() ), -1 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( Y() ), -1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( x ), -1 );
+        boost::compat::mem_fn( &X::m )( x ) = +1;
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( x ), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( &x ), -1 );
+        boost::compat::mem_fn( &X::m )( &x ) = +1;
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( &x ), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::ref(x) ), -1 );
+        boost::compat::mem_fn( &X::m )( std::ref(x) ) = +1;
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::ref(x) ), +1 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::cref(x) ), -1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( y ), -1 );
+        boost::compat::mem_fn( &X::m )( y ) = +1;
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( y ), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( &y ), -1 );
+        boost::compat::mem_fn( &X::m )( &y ) = +1;
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( &y ), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::ref(y) ), -1 );
+        boost::compat::mem_fn( &X::m )( std::ref(y) ) = +1;
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::ref(y) ), +1 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::cref(y) ), -1 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( x ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::ref(x) ), -1 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( y ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::m )( std::ref(y) ), -1 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/mem_fn_mfn_test.cpp
+++ b/test/mem_fn_mfn_test.cpp
@@ -0,0 +1,127 @@
+// Copyright 2024 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#if defined(__GNUC__) && __GNUC__ == 7
+# pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/mem_fn.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <functional>
+
+struct X
+{
+    int f0()
+    {
+        return -1;
+    }
+
+    int f1( int x1 ) noexcept
+    {
+        return x1;
+    }
+
+    int f2( int x1, int x2 ) const
+    {
+        return 10*x1+x2;
+    }
+
+    int f3( int x1, int x2, int x3 ) const noexcept
+    {
+        return 100*x1 + 10*x2 + x3;
+    }
+};
+
+struct Y: public virtual X
+{
+};
+
+int main()
+{
+    {
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( X() ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( X(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( X(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( X(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( Y() ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( Y(), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( Y(), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( Y(), 1, 2, 3 ), 123 );
+    }
+
+    {
+        X x;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( x ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( &x ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( &x, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( std::ref(x) ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( std::ref(x), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( std::cref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( std::cref(x), 1, 2, 3 ), 123 );
+    }
+
+    {
+        Y y;
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( y ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( &y ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( &y, 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( &y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f0 )( std::ref(y) ), -1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f1 )( std::ref(y), 1 ), 1 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( std::ref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( std::ref(y), 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( std::cref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( std::cref(y), 1, 2, 3 ), 123 );
+    }
+
+    {
+        X const x = {};
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( &x, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( &x, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( std::ref(x), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( std::ref(x), 1, 2, 3 ), 123 );
+    }
+
+    {
+        Y const y = {};
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( &y, 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( &y, 1, 2, 3 ), 123 );
+
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f2 )( std::ref(y), 1, 2 ), 12 );
+        BOOST_TEST_EQ( boost::compat::mem_fn( &X::f3 )( std::ref(y), 1, 2, 3 ), 123 );
+    }
+
+    return boost::report_errors();
+}
--- a/test/move_only_function_test.cpp
+++ b/test/move_only_function_test.cpp
@@ -0,0 +1,855 @@
+#include <boost/config.hpp>
+#include <boost/config/workaround.hpp>
+
+#if BOOST_WORKAROUND(BOOST_GCC, >= 7 * 10000 && BOOST_GCC < 8 * 10000)
+#   pragma GCC diagnostic push
+#   pragma GCC diagnostic ignored "-Wnoexcept-type"
+#endif
+
+#include <boost/compat/move_only_function.hpp>
+
+#include <boost/compat/invoke.hpp>
+
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+
+#include <functional>
+#include <memory>
+#include <type_traits>
+
+#if BOOST_WORKAROUND(BOOST_GCC, >= 13 * 10000)
+#   pragma GCC diagnostic push
+#   pragma GCC diagnostic ignored "-Wself-move"
+#elif defined(BOOST_CLANG)
+#   pragma clang diagnostic push
+#   pragma clang diagnostic ignored "-Wself-move"
+#endif
+
+using std::is_same;
+using std::is_constructible;
+using std::is_nothrow_constructible;
+
+using boost::compat::move_only_function;
+using boost::compat::in_place_type_t;
+// using std::move_only_function;
+// using std::in_place_type_t;
+using boost::compat::invoke_result_t;
+using boost::compat::is_invocable;
+using boost::compat::is_nothrow_invocable;
+
+template<class T>
+using add_const_t = typename std::add_const<T>::type;
+
+template<class T>
+constexpr add_const_t<T>& as_const_ref( T& t ) noexcept
+{
+    return t;
+}
+
+void func0() {}
+
+int func1()
+{
+    return 1;
+}
+
+int func2( int x )
+{
+    return x + 1;
+}
+
+int func3( std::unique_ptr<int> x )
+{
+    return *x + 1;
+}
+
+template<class T, class ...Args>
+std::unique_ptr<T> make_unique( Args&&... args )
+{
+    return std::unique_ptr<T>( new T( std::forward<Args>( args )... ) );
+}
+
+struct callable
+{
+    std::unique_ptr<int> p_ = make_unique<int>( 1 );
+
+    callable() = default;
+
+    callable( std::unique_ptr<int> p ): p_( std::move( p ) )
+    {
+    }
+
+    callable( std::initializer_list<int> il, int x, int y, int z )
+    {
+        int sum = 0;
+        for( auto const v : il )
+        {
+            sum += v;
+        }
+        sum += x;
+        sum += y;
+        sum += z;
+        p_ = make_unique<int>( sum );
+    }
+
+    callable( callable&& rhs ) noexcept
+    {
+        p_ = make_unique<int>( *rhs.p_ );
+    }
+
+    int operator()( int x )
+    {
+        return *p_ + x;
+    }
+};
+
+struct noex_callable
+{
+    std::unique_ptr<int> p_ = make_unique<int>( 1 );
+
+    noex_callable() = default;
+    noex_callable( noex_callable&& rhs ) noexcept
+    {
+        p_ = make_unique<int>( *rhs.p_ );
+    }
+
+    noex_callable( noex_callable const& )
+    {
+    }
+
+    int operator()( int x ) noexcept
+    {
+        return *p_ + x;
+    }
+};
+
+struct large_callable
+{
+    unsigned char padding[ 256 ] = {};
+    std::unique_ptr<int> p_ = make_unique<int>( 1 );
+
+    large_callable() = default;
+
+    large_callable( std::unique_ptr<int> p ): p_( std::move( p ) )
+    {
+    }
+
+    large_callable( large_callable&& rhs ) noexcept
+    {
+        p_ = make_unique<int>( *rhs.p_ );
+    }
+
+    int operator()( int x )
+    {
+        return *p_ + x;
+    }
+
+    int operator()( int x, int y )
+    {
+        return x + y;
+    }
+};
+
+struct person
+{
+    std::string name_;
+    int age_ = -1;
+    std::unique_ptr<int> p_ = make_unique<int>( 1 );
+
+    int age()
+    {
+        return age_;
+    }
+};
+
+static void test_call()
+{
+    {
+        move_only_function<int()> f1;
+        BOOST_TEST( !f1 );
+
+        move_only_function<int() const> f2;
+        BOOST_TEST( !f2 );
+    }
+
+    {
+        move_only_function<int()> f1( nullptr );
+        BOOST_TEST( !f1 );
+
+        move_only_function<int() const> f2( nullptr );
+        BOOST_TEST( !f2 );
+    }
+
+    {
+        move_only_function<void()> f1( func0 );
+        f1();
+        BOOST_TEST( f1 );
+
+        move_only_function<void() const> f2( func0 );
+        f2();
+        BOOST_TEST( f2 );
+    }
+
+    {
+        int ( *fp )() = [] { return 0; };
+
+        move_only_function<int()> f1( fp );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1(), 0 );
+        BOOST_TEST_EQ( std::move( f1() ), 0 );
+
+        move_only_function<int() const> f2( fp );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2(), 0 );
+        BOOST_TEST_EQ( std::move( f2() ), 0 );
+
+        fp = nullptr;
+        move_only_function<int() const> f3( fp );
+        BOOST_TEST_NOT( f3 );
+    }
+
+    {
+        struct declared;
+        enum class integer : int;
+
+        move_only_function<void(declared)> f1;
+        move_only_function<void(declared&)> f2;
+        move_only_function<void(declared&&)> f3;
+        move_only_function<void(integer)> f4;
+    }
+
+    {
+        move_only_function<int()> f1( func1 );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f1() ), 1 );
+
+        move_only_function<int() const> f2( func1 );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2(), 1 );
+        BOOST_TEST_EQ( std::move( f2() ), 1 );
+    }
+
+    {
+        move_only_function<int( std::unique_ptr<int> )> fn( func3 );
+        BOOST_TEST_EQ( fn( make_unique<int>( 1 ) ), 2 );
+        BOOST_TEST_EQ( std::move( fn )( make_unique<int>( 1 ) ), 2 );
+
+        auto x = make_unique<int>( 1 );
+        BOOST_TEST( fn );
+        BOOST_TEST_EQ( fn( std::move( x ) ), 2 );
+    }
+
+    {
+        auto l = []() { return 1; };
+
+        move_only_function<int()> f1( l );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f1 )(), 1 );
+
+        move_only_function<int() const> f2( l );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2(), 1 );
+        BOOST_TEST_EQ( as_const_ref( f2 )(), 1 );
+        BOOST_TEST_EQ( std::move( f2 )(), 1 );
+        BOOST_TEST_EQ( std::move( as_const_ref( f2 ) )(), 1 );
+    }
+
+    {
+        move_only_function<int()> f1( []() { return 1; } );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f1 )(), 1 );
+
+        move_only_function<int() const> f2( []() { return 1; } );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2(), 1 );
+        BOOST_TEST_EQ( as_const_ref( f2 )(), 1 );
+        BOOST_TEST_EQ( std::move( f2 )(), 1 );
+        BOOST_TEST_EQ( std::move( as_const_ref( f2 ) )(), 1 );
+    }
+
+    {
+        auto l = []( int x ) { return x + 1; };
+
+        move_only_function<int( int )> f1( l );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1( 1 ), 2 );
+
+        move_only_function<int( int ) const> f2( l );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2( 1 ), 2 );
+    }
+
+    {
+        auto l = []( std::unique_ptr<int> x ) { return *x + 1; };
+        move_only_function<int( std::unique_ptr<int> )> f( std::move( l ) );
+        BOOST_TEST( f );
+        BOOST_TEST_EQ( f( make_unique<int>( 1 ) ), 2 );
+    }
+
+    {
+        auto p = make_unique<int>( 1 );
+        auto l = []( std::unique_ptr<int>& x ) { return *x + 1; };
+        move_only_function<int( std::unique_ptr<int>& )> f( l );
+        BOOST_TEST( f );
+        BOOST_TEST_EQ( f( p ), 2 );
+    }
+
+    {
+        int x = 1;
+        move_only_function<int( int )> f1( callable{} );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1( 1 ), 2);
+        BOOST_TEST_EQ( f1( x ), 2 );
+
+        int y = 2;
+        callable c;
+        move_only_function<int( int )> f2( std::move( c ) );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2( 2 ), 3 );
+        BOOST_TEST_EQ( f2( y ), 3 );
+    }
+
+    {
+        move_only_function<int( int, int )> f1( large_callable{} );
+        BOOST_TEST( f1 );
+        BOOST_TEST_EQ( f1( 1, 2 ), 3);
+
+        large_callable c;
+        move_only_function<int( int, int )> f2( std::move( c ) );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2( 1, 2 ), 3 );
+    }
+
+    {
+        move_only_function<int( int )> f1( in_place_type_t<callable>{}, make_unique<int>( 4321 ) );
+        BOOST_TEST_EQ( f1( 1234 ), 5555 );
+
+        move_only_function<int( int )> f2( in_place_type_t<large_callable>{}, make_unique<int>( 4321 ) );
+        BOOST_TEST_EQ( f2( 1234 ), 5555 );
+
+        move_only_function<int( int )> f3( in_place_type_t<int(*)( int )>{}, func2 );
+        BOOST_TEST_EQ( f3( 1233 ), 1234 );
+
+        move_only_function<int( int )> f4( in_place_type_t<int(*)( int )>{} );
+        BOOST_TEST( f4 != nullptr );
+
+        move_only_function<int( int )> f5( in_place_type_t<callable>{}, std::initializer_list<int>{ 1, 2, 3 }, 4, 5, 6 );
+        BOOST_TEST_EQ( f5( 7 ), 1 + 2 + 3 + 4 + 5 + 6 + 7 );
+    }
+
+    {
+        move_only_function<int()> f1( func1 );
+        move_only_function<int()> f2( std::move( f1 ) );
+
+        BOOST_TEST( !f1 );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2(), 1 );
+    }
+
+    {
+        move_only_function<int( int )> f1( callable{} );
+        move_only_function<int( int )> f2( std::move( f1 ) );
+
+        BOOST_TEST( !f1 );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2( 2 ), 3 );
+    }
+
+    {
+        move_only_function<int( int, int )> f1( large_callable{} );
+        move_only_function<int( int, int )> f2( std::move( f1 ) );
+
+        BOOST_TEST( !f1 );
+        BOOST_TEST( f2 );
+        BOOST_TEST_EQ( f2( 1, 2 ), 3 );
+    }
+
+    {
+        person p;
+        p.age_ = 35;
+
+        move_only_function<int( person& )> f1( &person::age_ );
+        BOOST_TEST_EQ( f1( p ), 35 );
+
+        p.age_ = 53;
+
+        move_only_function<int( person& )> f2( &person::age );
+        BOOST_TEST_EQ( f2( p ), 53 );
+
+        int person::*mp = nullptr;
+        move_only_function<int( person& )> f3( mp );
+        BOOST_TEST_NOT( f3 );
+
+        int (person::*mfp)() = nullptr;
+        move_only_function<int( person& )> f4( mfp );
+        BOOST_TEST_NOT( f4 );
+    }
+
+    {
+        struct tester
+        {
+            int operator()()
+            {
+                return 1;
+            }
+
+            int operator()() const
+            {
+                return 2;
+            }
+        };
+
+        tester t;
+
+        move_only_function<int()> f1( t );
+        move_only_function<int() const> f2( t );
+
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f1 )(), 1 );
+        BOOST_TEST_EQ( f2(), 2 );
+        BOOST_TEST_EQ( as_const_ref( f2 )(), 2 );
+        BOOST_TEST_EQ( std::move( as_const_ref( f2 ) )(), 2 );
+    }
+
+    {
+        struct tester
+        {
+            int operator()() noexcept
+            {
+                return 1;
+            }
+
+            int operator()() const noexcept
+            {
+                return 2;
+            }
+        };
+
+        tester t;
+
+        move_only_function<int() noexcept> f1( t );
+        move_only_function<int() const noexcept> f2( t );
+
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f1 )(), 1 );
+        BOOST_TEST_EQ( f2(), 2 );
+        BOOST_TEST_EQ( as_const_ref( f2 )(), 2 );
+        BOOST_TEST_EQ( std::move( as_const_ref( f2 ) )(), 2 );
+    }
+
+    {
+        struct tester
+        {
+            int operator()() &
+            {
+                return 1;
+            }
+
+            int operator()() &&
+            {
+                return 2;
+            }
+
+            int operator()() const&
+            {
+                return 3;
+            }
+
+            int operator()() const&&
+            {
+                return 4;
+            }
+        };
+
+        tester t;
+
+        move_only_function<int() &> f1( t );
+        move_only_function<int() &&> f2( t );
+        move_only_function<int() const&> f3( t );
+
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f2 )(), 2 );
+        BOOST_TEST_EQ( f3(), 3 );
+        BOOST_TEST_EQ( as_const_ref( f3 )(), 3 );
+
+#if !BOOST_WORKAROUND(BOOST_GCC, < 40900)
+
+        move_only_function<int() const&&> f4( t );
+        BOOST_TEST_EQ( std::move( f4 )(), 4 );
+        BOOST_TEST_EQ( std::move( as_const_ref( f4 ) )(), 4 );
+
+#endif
+    }
+
+    {
+        struct tester
+        {
+            int operator()() & noexcept
+            {
+                return 1;
+            }
+
+            int operator()() && noexcept
+            {
+                return 2;
+            }
+
+            int operator()() const& noexcept
+            {
+                return 3;
+            }
+
+            int operator()() const&& noexcept
+            {
+                return 4;
+            }
+        };
+
+        tester t;
+
+        move_only_function<int() &> f1( t );
+        move_only_function<int() &&> f2( t );
+        move_only_function<int() const&> f3( t );
+
+        BOOST_TEST_EQ( f1(), 1 );
+        BOOST_TEST_EQ( std::move( f2 )(), 2 );
+        BOOST_TEST_EQ( f3(), 3 );
+        BOOST_TEST_EQ( as_const_ref( f3 )(), 3 );
+
+#if !BOOST_WORKAROUND(BOOST_GCC, < 40900)
+
+        move_only_function<int() const&&> f4( t );
+        BOOST_TEST_EQ( std::move( f4 )(), 4 );
+        BOOST_TEST_EQ( std::move( as_const_ref( f4 ) )(), 4 );
+
+#endif
+    }
+
+    {
+        move_only_function<int( int )> f1( callable{} );
+        // f1 = std::move( f1 );
+        // BOOST_TEST_EQ( f1( 1233 ), 1234 );
+
+        move_only_function<int( int )> f2( large_callable{} );
+        f2 = std::move( f1 );
+        BOOST_TEST_EQ( f2( 1233 ), 1234 );
+        BOOST_TEST_NOT( f1 );
+
+        move_only_function<int( int )> f3( callable{} );
+        move_only_function<int( int )> f4( large_callable{} );
+        f3 = std::move( f4 );
+        BOOST_TEST_EQ( f3( 1233 ), 1234 );
+        BOOST_TEST_NOT( f4 );
+
+        move_only_function<int( int )> f5( callable{} );
+        f5 = nullptr;
+        BOOST_TEST_NOT( f5 );
+
+        move_only_function<int( int )> f6( large_callable{} );
+        f6 = nullptr;
+        BOOST_TEST_NOT( f6 );
+
+        move_only_function<int( int )> f7;
+        f7 = nullptr;
+        BOOST_TEST_NOT( f7 );
+
+        move_only_function<int( int )> f8( callable{} );
+        f8 = large_callable{};
+        BOOST_TEST_EQ( f8( 1233 ), 1234 );
+
+        move_only_function<int( int )> f9( large_callable{} );
+        f9 = callable{};
+        BOOST_TEST_EQ( f9( 1233 ), 1234 );
+
+        move_only_function<int( int )> f10;
+        f10 = callable{};
+        BOOST_TEST_EQ( f10( 1233 ), 1234 );
+
+        move_only_function<int( int )> f11;
+        f11 = large_callable{};
+        BOOST_TEST_EQ( f11( 1233 ), 1234 );
+    }
+
+    {
+        callable c1;
+        *c1.p_ = 1234;
+
+        large_callable c2;
+        *c2.p_ = 4321;
+
+        move_only_function<int( int )> f1( std::move( c1 ) );
+        move_only_function<int( int )> f2( std::move( c2 ) );
+
+        int x = 1;
+
+        BOOST_TEST_EQ( f1( x ), 1235 );
+        BOOST_TEST_EQ( f2( x ), 4322 );
+
+        swap( f1, f2 );
+
+        BOOST_TEST_EQ( f1( x ), 4322 );
+        BOOST_TEST_EQ( f2( x ), 1235 );
+
+        move_only_function<int( int )> f3( callable{} );
+        move_only_function<int( int )> f4;
+
+        swap( f3, f4 );
+        BOOST_TEST_NOT( f3 );
+        BOOST_TEST( f4 );
+
+        move_only_function<int( int )> f5;
+        move_only_function<int( int )> f6;
+
+        swap( f5, f6 );
+        BOOST_TEST_NOT( f5 );
+        BOOST_TEST_NOT( f6 );
+    }
+
+    {
+        struct throwing
+        {
+            static int x()
+            {
+                throw 1234;
+            }
+
+            int operator()()
+            {
+                throw 1234;
+            }
+        };
+
+        struct large_throwing
+        {
+            char padding[ 256 ] = {};
+
+            int operator()()
+            {
+                throw 1234;
+            }
+        };
+
+        move_only_function<int()> f1( &throwing::x );
+        move_only_function<int()> f2( throwing{} );
+        move_only_function<int()> f3( large_throwing{} );
+
+        BOOST_TEST_THROWS( f1(), int );
+        BOOST_TEST_THROWS( f2(), int );
+        BOOST_TEST_THROWS( f3(), int );
+    }
+}
+
+struct Q
+{
+    void operator()() const &;
+    void operator()() &&;
+};
+
+struct R
+{
+    void operator()() &;
+    void operator()() &&;
+};
+
+// These types are all small and nothrow move constructible
+struct F { void operator()(); };
+struct G { void operator()() const; };
+
+struct H
+{
+    H( int );
+    H( int, int ) noexcept;
+    void operator()() noexcept;
+};
+
+struct I
+{
+    I( int, const char* );
+    I( std::initializer_list<char> );
+    int operator()() const noexcept;
+};
+
+static void test_traits()
+{
+    // just copy the static assertions from libstdc++'s test suite, call.cc, cons.cc, conv.cc
+
+    // Check return types
+    BOOST_TEST_TRAIT_TRUE( ( is_same<void, invoke_result_t<move_only_function<void()>>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_same<int, invoke_result_t<move_only_function<int()>>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_same<int&, invoke_result_t<move_only_function<int&()>>> ) );
+
+    // With const qualifier
+    BOOST_TEST_TRAIT_FALSE( ( is_invocable< move_only_function<void()> const > ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_invocable< move_only_function<void()> const &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> const > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> const &> ) );
+
+    // With no ref-qualifier
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void()> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void()> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> const > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const> const &> ) );
+
+    // With & ref-qualifier
+    BOOST_TEST_TRAIT_FALSE( ( is_invocable< move_only_function<void()&> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void()&> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const&> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const&> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const&> const > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const&> const &> ) );
+
+    // With && ref-qualifier
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void()&&> > ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_invocable< move_only_function<void()&&> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const&&> > ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_invocable< move_only_function<void() const&&> &> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_invocable< move_only_function<void() const&&> const > ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_invocable< move_only_function<void() const&&> const &> ) );
+
+    #if defined(__cpp_noexcept_function_type)
+
+    // With noexcept-specifier
+    BOOST_TEST_TRAIT_FALSE( ( is_nothrow_invocable< move_only_function<void()> > ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_nothrow_invocable< move_only_function<void() noexcept(false)> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_invocable< move_only_function<void() noexcept> > ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_invocable< move_only_function<void()& noexcept>& > ) );
+
+    #endif
+
+    BOOST_TEST_TRAIT_TRUE( ( std::is_nothrow_default_constructible<move_only_function<void()>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void()>, std::nullptr_t> ) );
+    BOOST_TEST_TRAIT_TRUE( ( std::is_nothrow_move_constructible<move_only_function<void()>> ) );
+    BOOST_TEST_TRAIT_FALSE( ( std::is_copy_constructible<move_only_function<void()>> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, void()> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, void( & )()> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, void( * )()> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, int()> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, int( & )()> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, int( * )()> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void()>, void( int )> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void(int)>, void( int )> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void( int )>, in_place_type_t<void(*)( int )>, void( int )> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, void() noexcept> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void() noexcept>, void() noexcept> ) );
+
+#if defined(__cpp_noexcept_function_type)
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void() noexcept>, void()> ) );
+#endif
+
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, Q> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void() const>, Q> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void() &>, Q> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void() const &>, Q> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void() &&>, Q> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void() const &&>, Q> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, R> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()&>, R> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()&&>, R> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void() const>, R> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void() const&>, R> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void() const&&>, R> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void()>, F> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void()>, G> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void() const>, G> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void()>, H> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void() noexcept>, H> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_nothrow_constructible<move_only_function<void() noexcept >, in_place_type_t<H>, int> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_nothrow_constructible<move_only_function<void() noexcept>, in_place_type_t<H>, int, int> ) );
+
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, in_place_type_t<I>, int, const char*> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_constructible<move_only_function<void()>, in_place_type_t<I>, std::initializer_list<char>> ) );
+
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void()>, move_only_function<void() &>> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void()>, move_only_function<void() &&>> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void()&>, move_only_function<void() &&>> ) );
+    BOOST_TEST_TRAIT_FALSE( ( is_constructible<move_only_function<void() const>, move_only_function<void()>> ) );
+
+    using FuncType = int( int );
+
+    // Top level const qualifiers are ignored in function types, and decay
+    // is performed.
+    BOOST_TEST_TRAIT_TRUE( ( is_same<move_only_function<void( int const )>, move_only_function<void( int )>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_same<move_only_function<void( int[ 2 ] )>, move_only_function<void( int* )>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_same<move_only_function<void( int[] )>, move_only_function<void( int* )>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_same<move_only_function<void(int const[ 5 ])>, move_only_function<void( int const* )>> ) );
+    BOOST_TEST_TRAIT_TRUE( ( is_same<move_only_function<void( FuncType )>, move_only_function<void( FuncType* )>> ) );
+}
+
+static void test_conv()
+{
+    {
+        noex_callable nt;
+
+        move_only_function<int( int ) noexcept> f1( std::move( nt ) );
+        move_only_function<int( int )> f2( std::move( f1 ) );
+        BOOST_TEST_EQ( f2( 1234 ), 1235 );
+    }
+
+    {
+        auto l = []( noex_callable const& c ) noexcept { return *c.p_ + 1234; };
+
+        noex_callable c;
+
+        move_only_function<int( noex_callable ) const noexcept> f1( l );
+        BOOST_TEST_EQ( f1( c ), 1235 );
+
+        move_only_function<int( noex_callable ) const> f2( std::move( f1 ) );
+        BOOST_TEST_EQ( f2( c ), 1235 );
+
+        move_only_function<int( noex_callable )> f3( std::move( f2 ) );
+        BOOST_TEST_EQ( f3( c ), 1235 );
+
+        move_only_function<int( noex_callable&& )> f4( std::move( f3 ) );
+        BOOST_TEST_EQ( f4( noex_callable{} ), 1235 );
+
+        move_only_function<int( noex_callable&& ) &&> f5( std::move( f4 ) );
+        BOOST_TEST_EQ( std::move( f5 )( noex_callable{} ), 1235 );
+
+        move_only_function<int( noex_callable&& )> f6( l );
+
+        move_only_function<int( noex_callable&& ) &> f7( std::move( f6 ) );
+        BOOST_TEST_EQ( f7( noex_callable{} ), 1235 );
+
+        // TODO: libstdc++ includes this test case but it seems like pedantically calling a `long(*)(Arg)` should
+        // be UB in the general sense. We need to confirm one way or another if this is something we need to support.
+        //
+        // move_only_function<int( noex_callable ) const noexcept> f8( l );
+        // move_only_function<long( noex_callable ) const noexcept> f9( std::move( f8 ) );
+        // BOOST_TEST_EQ( f9( noex_callable{} ), 1235 );
+    }
+
+    {
+        move_only_function<int( long ) const noexcept> e;
+        BOOST_TEST( e == nullptr );
+
+        move_only_function<int( long ) const> e2( std::move( e ) );
+        BOOST_TEST( e2 == nullptr );
+        e2 = std::move( e );
+        BOOST_TEST( e2 == nullptr );
+
+        move_only_function<int( long )> e3( std::move( e2 ) );
+        BOOST_TEST( e3 == nullptr );
+    }
+}
+
+int main()
+{
+    test_call();
+    test_traits();
+    test_conv();
+
+    return boost::report_errors();
+}
--- a/test/nontype_test.cpp
+++ b/test/nontype_test.cpp
@@ -0,0 +1,33 @@
+// Copyright 2025 Peter Dimov
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/detail/nontype.hpp>
+#include <boost/core/lightweight_test.hpp>
+#include <boost/core/lightweight_test_trait.hpp>
+#include <boost/config/pragma_message.hpp>
+
+#if !( defined(__cpp_nontype_template_parameter_auto) && __cpp_nontype_template_parameter_auto >= 201606L )
+
+BOOST_PRAGMA_MESSAGE("Test skipped, __cpp_nontype_template_parameter_auto is not defined to at least 201606L")
+int main() {}
+
+#else
+
+void f() {}
+
+struct X
+{
+    void f() {}
+};
+
+int main()
+{
+    BOOST_TEST_TRAIT_SAME( boost::compat::nontype_t< 5 > const, decltype( boost::compat::nontype< 5 > ) );
+    BOOST_TEST_TRAIT_SAME( boost::compat::nontype_t< ::f > const, decltype( boost::compat::nontype< ::f > ) );
+    BOOST_TEST_TRAIT_SAME( boost::compat::nontype_t< &X::f > const, decltype( boost::compat::nontype< &X::f > ) );
+
+    return boost::report_errors();
+}
+
+#endif
--- a/test/quick.cpp
+++ b/test/quick.cpp
@@ -3,6 +3,10 @@
 // https://www.boost.org/LICENSE_1_0.txt

 #include <boost/compat/latch.hpp>
+#include <boost/compat/shared_lock.hpp>
+#include <boost/compat/invoke.hpp>
+#include <boost/compat/bind_front.hpp>
+#include <boost/compat/bind_back.hpp>

 int main()
 {
--- a/test/shared_lock_test.cpp
+++ b/test/shared_lock_test.cpp
@@ -1,3 +1,9 @@
+// Copyright 2023 Peter Dimov.
+// Copyright 2023 Christian Mazakas.
+// Copyright 2023 Ed Catmur
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
 #ifdef _MSC_VER
 #pragma warning(disable: 4530) // C++ exception handler used, but unwing semantics not enabled
 #pragma warning(disable: 4577) // noexcept used with no exception handling mode specified
--- a/test/to_array_lvalue_test.cpp
+++ b/test/to_array_lvalue_test.cpp
@@ -0,0 +1,60 @@
+// Copyright 2024 Ruben Perez Hidalgo.
+// Distributed under the Boost Software License, Version 1.0.
+// https://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/compat/to_array.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+#include <array>
+#include <vector>
+
+namespace compat = boost::compat;
+
+int main()
+{
+    {
+        // regular C array
+        int input[] = {1, 2};
+        auto output = compat::to_array(input);
+        static_assert(std::is_same<decltype(output), std::array<int, 2>>::value, "");
+        BOOST_TEST_EQ(output[0], 1);
+        BOOST_TEST_EQ(output[1], 2);
+    }
+    {
+        // regular C array, const
+        const int input[] = {1, 2};
+        auto output = compat::to_array(input);
+        static_assert(std::is_same<decltype(output), std::array<int, 2>>::value, "");
+        BOOST_TEST_EQ(output[0], 1);
+        BOOST_TEST_EQ(output[1], 2);
+    }
+    {
+        // values not moved
+        const std::vector<int> vec{1, 2};
+        std::vector<int> input[]{vec};
+        auto output = compat::to_array(input);
+        static_assert(std::is_same<decltype(output), std::array<std::vector<int>, 1>>::value, "");
+        BOOST_TEST_ALL_EQ(output[0].begin(), output[0].end(), vec.begin(), vec.end());
+        BOOST_TEST_ALL_EQ(input[0].begin(), input[0].end(), vec.begin(), vec.end());  // input not modified
+    }
+    {
+        // const values work
+        const std::vector<int> vec{1, 2};
+        const std::vector<int> input[]{vec};
+        auto output = compat::to_array(input);
+        static_assert(std::is_same<decltype(output), std::array<std::vector<int>, 1>>::value, "");
+        BOOST_TEST_ALL_EQ(output[0].begin(), output[0].end(), vec.begin(), vec.end());
+        BOOST_TEST_ALL_EQ(input[0].begin(), input[0].end(), vec.begin(), vec.end());  // input not modified
+    }
+    {
+        // constexpr check
+        constexpr int input[] = {1, 2, 3};
+        constexpr auto output = compat::to_array(input);
+        static_assert(std::is_same<decltype(output), const std::array<int, 3>>::value, "");
+        BOOST_TEST_EQ(output[0], 1);
+        BOOST_TEST_EQ(output[1], 2);
+        BOOST_TEST_EQ(output[2], 3);
+    }
+
+    return boost::report_errors();
+}
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Peter Dimov	7ce75ac955	Update ci.yml	2026-01-16 02:16:52 +02:00
Peter Dimov	0776d62a95	Update documentation	2025-11-18 14:33:45 +02:00
Peter Dimov	904b80b8a1	Move nontype.hpp to detail	2025-11-18 14:33:45 +02:00
Peter Dimov	ffaadc079d	Update .drone.jsonnet	2025-11-18 12:06:25 +02:00
Peter Dimov	ab09450342	Update documentation of function_ref	2025-11-03 18:54:47 +02:00
Peter Dimov	79ca9646ea	Update documentation of nontype to clarify that it requires C++17	2025-11-03 18:41:18 +02:00
Peter Dimov	6b9e52c284	Rename detail::nontype11 to nttp_holder	2025-11-01 19:45:39 +02:00
Peter Dimov	4c9e9079c1	Remove feature check for variable templates; if we have auto template parameters (C++17) we probably have C++14 as well	2025-11-01 19:32:34 +02:00
Peter Dimov	e522245e9c	Remove uses of is_rvalue_reference_v	2025-11-01 19:21:51 +02:00
Peter Dimov	cef4d529d0	Remove BOOST_COMPAT_HAS_AUTO_NTTP	2025-11-01 19:16:17 +02:00
Peter Dimov	1e3cb9cc7a	Disable tests that require noexcept function types to pass	2025-11-01 19:15:14 +02:00
Peter Dimov	1226bab251	Remove use of BOOST_COMPAT_HAS_AUTO_NTTP in function_ref_mfn_noexcept_test.cpp	2025-11-01 19:00:44 +02:00
Peter Dimov	f9dd6181fb	Remove use of BOOST_COMPAT_HAS_AUTO_NTTP in function_ref_mfn_test.cpp	2025-11-01 18:51:37 +02:00
Peter Dimov	db39b5075c	Add a C++11 compatible base class to nontype_t; unconditionally enable the function_ref constructors for it	2025-11-01 18:36:05 +02:00
Peter Dimov	f72aeb4e59	Update documentation	2025-11-01 17:57:22 +02:00
Peter Dimov	8e7e16e9c3	Add nontype_test.cpp	2025-11-01 17:18:55 +02:00
Peter Dimov	f897f32064	Extract nontype_t to its own header; add nontype	2025-11-01 17:07:54 +02:00
Peter Dimov	a5a56ee5c0	Merge pull request #22 from k3DW/to_underlying Add `to_underlying`	2025-09-05 18:48:05 +03:00
Braden Ganetsky	72ff680a72	Fix function signature in to_array docs	2025-09-05 09:33:40 -05:00
Braden Ganetsky	94b1675762	Add to_underlying	2025-09-05 09:33:40 -05:00
Peter Dimov	694b78df7a	Update ci.yml	2025-09-04 16:08:07 +03:00
Peter Dimov	e374640265	Remove windows-2019 from ci.yml	2025-07-02 19:06:07 +03:00
Christian Mazakas	f496e814b5	update changelog	2025-07-02 07:12:23 -07:00
Peter Dimov	10e1dad9ba	Merge pull request #21 from cmazakas/feature/move-only-function add move_only_function	2025-06-28 17:52:06 +03:00
Christian Mazakas	6172b5e50f	add move_only_function docs	2025-06-11 19:57:40 -07:00
Christian Mazakas	1a60e0357c	add move_only_function	2025-06-11 19:57:30 -07:00
Christian Mazakas	6901952904	remove ubuntu 20 from posix cmake gha jobs	2025-05-29 15:26:16 -07:00
Christian Mazakas	a1eb40bd0e	update gha to use containers	2025-05-29 15:26:16 -07:00
Christian Mazakas	61b464c3ee	Merge pull request #17 from cmazakas/fix/lvalue-params fix lvalue parameter passing	2024-12-17 12:49:24 -08:00
Christian Mazakas	c3bd40856d	remove erroneous rvalue qualification	2024-12-17 11:20:57 -08:00
Christian Mazakas	736b381d13	add failing test case Passing an lvalue ref parameter when arguments are by-value causes a failure of reference binding.	2024-12-17 11:20:18 -08:00
Peter Dimov	881cc909fb	Update .drone.jsonnet	2024-12-13 03:55:39 +02:00
Peter Dimov	c9f3354cff	Apply Node20 workaround	2024-12-13 03:34:16 +02:00
Peter Dimov	c4924db9e5	Update ci.yml	2024-12-13 03:21:42 +02:00
Peter Dimov	1a8bb0b574	Update revision history	2024-10-04 13:43:06 +03:00
Peter Dimov	c18e5f2276	Move MSVC workarounds from test/Jamfile to to_array_rvalue_test.cpp	2024-10-04 13:26:50 +03:00
Anarthal (Rubén Pérez)	d2d5cbe094	Added to_array (#14 ) * Added to_array * Suppress unused warnings * Fix unused warnings (2) * Workaround msvc 14.0 bug * Workaround MSVC problems with moving arrays * MSVC workaround in constexpr test * Further MSVC fixes * Disable rvalue tests for MSVC 14.0 * Incorrect argument spec * constexpr checks * const test * Disable rvalues for msvc 14.1 * Docs * Added more const tests * Correct static_asserts * Update type requirements in docs * Corrected return types and conditions * Doc updates	2024-10-04 13:06:44 +03:00
Peter Dimov	c49f822b2e	Update .drone.jsonnet	2024-08-21 10:49:04 +03:00
Peter Dimov	889d2608e6	Add VERBATIM to add_custom_target	2024-08-20 21:06:26 +03:00
Peter Dimov	787a5dd4d1	Update build.jam	2024-08-20 20:56:20 +03:00
Rene Rivera	a6520ef2e1	Sync from upstream.	2024-07-25 17:20:02 -05:00
Rene Rivera	0d2593326f	Move inter-lib dependencies to a project variable and into the build targets.	2024-07-23 22:34:24 -05:00
Peter Dimov	4abae7082a	Update ci.yml	2024-07-22 02:15:35 +03:00
Peter Dimov	d802b97ba8	Update .drone.jsonnet	2024-07-22 02:03:00 +03:00
Rene Rivera	e6d2faa267	Sync from upstream.	2024-07-12 08:55:45 -05:00
Peter Dimov	9244cd17b9	Merge pull request #11 from cmazakas/feature/function-ref-cpp17 implement pointer-to-member function_ref overloads	2024-06-22 20:09:56 +03:00
Christian Mazakas	37dbb81cce	add workaround for clang-7	2024-06-21 07:57:36 -07:00
Christian Mazakas	8ed23dd6a7	implement pointer-to-member function_ref overloads	2024-06-21 07:57:36 -07:00
Peter Dimov	915a207fc9	Merge pull request #12 from cmazakas/fix/obj-tests fix function_ref Callable constructor	2024-06-21 05:30:24 +03:00
Christian Mazakas	2a5e8031f8	fix erroneous handling of const types in function_ref callable constructor	2024-06-20 11:28:10 -07:00
Christian Mazakas	b9f5082f6e	expand fn object function_ref tests	2024-06-20 11:28:10 -07:00
Peter Dimov	6a0f933b2e	Update BOOST_MSVC workarounds for msvc-14.3 19.40	2024-06-19 03:38:32 +03:00
Peter Dimov	ef0f49933b	Update ci.yml	2024-06-19 03:36:09 +03:00
Rene Rivera	438e0fbbf3	Bump B2 require to 5.2	2024-06-14 11:33:55 -05:00
Rene Rivera	df5cd71735	Add requires-b2 check to top-level build file.	2024-05-05 09:00:00 -05:00
Rene Rivera	6f8c2fe8c1	Add missing import-search for cconfig/predef checks.	2024-05-04 23:28:15 -05:00
Rene Rivera	e5f0043abc	Sync from upstream.	2024-04-28 20:36:12 -05:00
Peter Dimov	fb5f95b3b2	Remove unnecessary GCC jobs from Drone	2024-04-28 20:57:41 +03:00
Peter Dimov	cc45f3198a	Disable -Warray-bounds on GCC when sanitization is on	2024-04-28 20:12:14 +03:00
Peter Dimov	ef87b7c225	Add Drone support	2024-04-28 19:12:02 +03:00
Peter Dimov	257ce0b4bd	Update ci.yml	2024-04-28 13:48:18 +03:00
Peter Dimov	ea462a4363	Update revision history	2024-04-28 13:45:11 +03:00
Rene Rivera	d5cf9802bd	Add new lib dependencies.	2024-04-25 22:12:11 -05:00
Rene Rivera	28496a6a01	Sync from upstream.	2024-04-20 15:34:30 -05:00
Peter Dimov	09dd50c8db	Merge pull request #10 from cmazakas/feature/function-ref add c++11 version of `function_ref`	2024-04-17 20:49:09 +03:00
Christian Mazakas	f969df9b2a	Add workaround for msvc-14.1	2024-04-17 10:12:05 -07:00
Christian Mazakas	74d9d80471	Add initial function_ref docs	2024-04-17 09:40:34 -07:00
Christian Mazakas	26e3edd0af	Add initial draft of function_ref	2024-04-17 09:40:34 -07:00
Christian Mazakas	09d1a51778	Add gitignore	2024-04-17 09:40:34 -07:00
Peter Dimov	f0aeb3ba95	Revert "Update doc/Jamfile" This reverts commit `0afd51fcd3`.	2024-04-16 22:37:08 +03:00
Peter Dimov	0afd51fcd3	Update doc/Jamfile	2024-04-16 22:16:08 +03:00
Rene Rivera	ed8837a4ff	Sync from upstream.	2024-04-10 07:58:31 -05:00
Peter Dimov	54c72a5033	Update documentation	2024-04-06 22:56:05 +03:00
Peter Dimov	2bc168926b	Add is_nothrow_invocable_r	2024-04-06 22:20:25 +03:00
Peter Dimov	3025c1b929	Add is_invocable_r	2024-04-06 21:45:34 +03:00
Peter Dimov	04e6d2ce20	Remove unnecessary includes	2024-04-06 21:45:34 +03:00
Peter Dimov	8cfda56a62	Add constexpr tests for invoke_r	2024-04-06 21:45:19 +03:00
Peter Dimov	430c9b1b60	Add noexcept tests for invoke_r	2024-04-06 20:12:13 +03:00
Peter Dimov	a91461a442	Fix C++11 constexpr errors in invoke_r<void>	2024-04-06 19:45:44 +03:00
Peter Dimov	984d6b39da	Add invoke_r	2024-04-06 19:03:58 +03:00
Peter Dimov	87e758f538	Update meta/libraries.json	2024-03-31 22:38:49 +03:00
Peter Dimov	ab2670f0a8	Merge pull request #9 from ashtum/resolve-mem_fn_ambiguity Qualify call to `mem_fn`	2024-03-31 17:23:43 +03:00
Mohammad Nejati	0561949e15	Qualify call to `mem_fn`	2024-03-31 10:05:25 +00:00
Peter Dimov	5e88ebb1d1	Fix changelog	2024-03-30 22:24:04 +02:00
Peter Dimov	d071dfc91f	Update documentation	2024-03-30 21:54:03 +02:00
Rene Rivera	7fc7795d6b	Switch to library requirements instead of source. As source puts extra source in install targets.	2024-03-29 21:15:58 -05:00
Peter Dimov	30242af2c2	Add constexpr tests for bind_back	2024-03-29 21:43:34 +02:00
Peter Dimov	9a58caf918	Add bind_back	2024-03-29 21:20:49 +02:00
Peter Dimov	28e71552eb	Add integer_sequence_test	2024-03-28 21:37:43 +02:00
Peter Dimov	10ad6ab592	Add boost/compat/integer_sequence.hpp	2024-03-28 21:28:20 +02:00
Peter Dimov	39ddb40a47	Update test/quick.cpp	2024-03-28 21:13:31 +02:00
Peter Dimov	928f2d7255	Add bind_front_md_constexpr_test	2024-03-28 21:12:46 +02:00
Peter Dimov	5a5db4a74f	Add bind_front_mfn_constexpr_test	2024-03-28 21:12:46 +02:00
Peter Dimov	acd8c12e91	Add bind_front_obj_constexpr_test	2024-03-28 21:12:46 +02:00
Peter Dimov	710ea6a904	Add bind_front_fn_constexpr_test	2024-03-28 21:12:46 +02:00
Peter Dimov	a09b9b2c5a	Add bind_front_md_test	2024-03-28 21:12:46 +02:00
Peter Dimov	758b0c2ef9	Add bind_front_mfn_test	2024-03-28 21:12:46 +02:00
Peter Dimov	4ea967b756	Avoid bind_front_obj_test failure on GCC 4.8	2024-03-28 21:12:46 +02:00
Peter Dimov	d745abe3a3	Disable invoke_mfn_constexpr_test, invoke_md_constexpr_test for GCC 4.9 as well	2024-03-28 21:12:46 +02:00
Peter Dimov	fa9180b234	Add GCC 4.9 to GHA	2024-03-28 21:12:46 +02:00
Peter Dimov	abcc654046	Add bind_front_obj_test	2024-03-28 21:12:46 +02:00
Peter Dimov	b6deff5638	Update bind_front_fn_test	2024-03-28 21:12:46 +02:00
Peter Dimov	90e76cb4f4	Add bind_front	2024-03-28 21:12:45 +02:00
Peter Dimov	c290c03ea3	Merge branch 'master' into develop	2024-03-28 21:12:12 +02:00
Peter Dimov	bba8d5f101	Update CMakeLists.txt	2024-03-28 20:32:41 +02:00
Peter Dimov	56b776fc29	Update test/quick.cpp	2024-03-28 20:31:36 +02:00
Rene Rivera	0598dd0688	Sync from upstream.	2024-03-23 07:58:05 -05:00
Peter Dimov	53c5bcf824	Disable is_nothrow_invocable under msvc-14.0	2024-03-22 19:15:09 +02:00
Peter Dimov	e270914326	Rephrase is_nothrow_invocable to not crash MSVC	2024-03-22 19:05:04 +02:00
Peter Dimov	5b6c4ffe95	Add is_nothrow_invocable	2024-03-22 18:38:10 +02:00
Peter Dimov	26e18fd796	Add is_invocable	2024-03-22 18:14:36 +02:00
Peter Dimov	571b48ca51	Add Boost::mp11 to test/CMakeLists.txt	2024-03-22 17:48:08 +02:00
Peter Dimov	b4b6cacb9d	Add invoke_result_t	2024-03-22 17:34:42 +02:00
Peter Dimov	6b0825b893	Disable invoke_mfn_constexpr_test and invoke_md_constexpr_test for GCC 4.8	2024-03-22 05:09:13 +02:00
Peter Dimov	dca886ef30	Add constexpr tests for invoke	2024-03-22 05:02:43 +02:00
Peter Dimov	4710db471a	Add noexcept tests for invoke	2024-03-22 02:35:29 +02:00
Peter Dimov	d83085a5d9	Add trailing return types to mem_fn for C++11	2024-03-21 21:37:10 +02:00
Peter Dimov	8633042b73	Add constexpr to mem_fn and invoke	2024-03-21 21:30:10 +02:00
Peter Dimov	eba152aa8e	Reimplement mem_fn	2024-03-21 21:27:04 +02:00
Peter Dimov	efff37c7a3	Add mem_fn_mfn_test, mem_fn_md_test	2024-03-21 21:00:34 +02:00
Peter Dimov	d745a4cfba	Disable -Wnoexcept-type under GCC 7	2024-03-21 20:43:25 +02:00
Peter Dimov	9743e1e03f	Add invoke_md_test	2024-03-21 20:28:27 +02:00
Peter Dimov	3980572c34	Add invoke_mfn_test	2024-03-21 20:21:58 +02:00
Peter Dimov	9cad6fbca9	Add invoke_obj_test	2024-03-21 20:12:01 +02:00
Peter Dimov	31fe10bf54	Update invoke_fn_test.cpp	2024-03-21 20:04:47 +02:00
Peter Dimov	b6858273bd	Add boost::compat::invoke	2024-03-21 19:57:32 +02:00
Peter Dimov	0220855d9c	Update ci.yml	2024-03-21 19:51:58 +02:00
Peter Dimov	91c2054151	Merge pull request #7 from cmazakas/missing-copyright Add missing copyright to shared_lock_test.cpp	2024-03-21 19:48:13 +02:00
Christian Mazakas	6153916abe	Add missing copyright to shared_lock_test.cpp	2024-03-21 10:41:17 -07:00
Rene Rivera	c511487e78	Make the library modular usable.	2024-03-11 08:27:02 -05:00