From fad52fc9125f29047c8b8e7bfa7c3de0dc4d44cd Mon Sep 17 00:00:00 2001
From: Paul <pfultz2@yahoo.com>
Date: Wed, 16 Mar 2016 12:58:49 -0500
Subject: [PATCH] Fixes for issue #118

---
 include/fit/by.hpp | 15 ++++++---------
 test/by.cpp        |  5 +++++
 test/capture.cpp   |  8 +++++++-
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/include/fit/by.hpp b/include/fit/by.hpp
index 8ec13e6..177e7b1 100644
--- a/include/fit/by.hpp
+++ b/include/fit/by.hpp
@@ -72,6 +72,7 @@
 #include <fit/detail/move.hpp>
 #include <fit/detail/make.hpp>
 #include <fit/detail/static_const_var.hpp>
+#include <fit/detail/compressed_pair.hpp>
 #include <fit/apply_eval.hpp>
 
 namespace fit {
@@ -160,19 +161,20 @@ template<class Projection, class F=void>
 struct by_adaptor;
 
 template<class Projection, class F>
-struct by_adaptor : detail::callable_base<Projection>, detail::callable_base<F>
+struct by_adaptor : detail::compressed_pair<detail::callable_base<Projection>, detail::callable_base<F>>
 {
     typedef by_adaptor fit_rewritable_tag;
+    typedef detail::compressed_pair<detail::callable_base<Projection>, detail::callable_base<F>> base;
     template<class... Ts>
     constexpr const detail::callable_base<F>& base_function(Ts&&... xs) const
     {
-        return always_ref(*this)(xs...);
+        return this->second(xs...);;
     }
 
     template<class... Ts>
     constexpr const detail::callable_base<Projection>& base_projection(Ts&&... xs) const
     {
-        return always_ref(*this)(xs...);
+        return this->first(xs...);
     }
 
     struct by_failure
@@ -191,12 +193,7 @@ struct by_adaptor : detail::callable_base<Projection>, detail::callable_base<F>
     : failure_map<by_failure, detail::callable_base<F>>
     {};
 
-    FIT_INHERIT_DEFAULT(by_adaptor, detail::callable_base<Projection>, F)
-
-    template<class P, class G, FIT_ENABLE_IF_CONVERTIBLE(P, detail::callable_base<Projection>), FIT_ENABLE_IF_CONVERTIBLE(G, detail::callable_base<F>)>
-    constexpr by_adaptor(P&& p, G&& f) 
-    : detail::callable_base<Projection>(FIT_FORWARD(P)(p)), detail::callable_base<F>(FIT_FORWARD(G)(f))
-    {}
+    FIT_INHERIT_CONSTRUCTOR(by_adaptor, base)
 
     FIT_RETURNS_CLASS(by_adaptor);
 
diff --git a/test/by.cpp b/test/by.cpp
index 817d0eb..aa1eb97 100644
--- a/test/by.cpp
+++ b/test/by.cpp
@@ -132,3 +132,8 @@ FIT_TEST_CASE()
 {
     FIT_STATIC_TEST_CHECK(constexpr_check_each()(bool_<true>()));
 }
+
+FIT_TEST_CASE()
+{
+    fit::by(fit::identity, fit::identity)(0);
+}
diff --git a/test/capture.cpp b/test/capture.cpp
index 08b57df..a0f75ba 100644
--- a/test/capture.cpp
+++ b/test/capture.cpp
@@ -1,5 +1,6 @@
-#include "test.hpp"
 #include <fit/capture.hpp>
+#include <fit/identity.hpp>
+#include "test.hpp"
 
 // TODO: Test empty capture
 
@@ -46,3 +47,8 @@ FIT_TEST_CASE()
     FIT_TEST_CHECK(fit::capture(add_member(1))(&add_member::add)(2) == 3);
 }
 
+FIT_TEST_CASE()
+{
+    fit::capture(fit::identity)(fit::identity)();
+}
+