diff --git a/example/stream.cpp b/example/stream.cpp
index dc0eae0..d7fc944 100644
--- a/example/stream.cpp
+++ b/example/stream.cpp
@@ -4,7 +4,7 @@
 
 #include "../test/test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
@@ -26,8 +26,6 @@ namespace cnv = boost::cnv;
 namespace arg = boost::cnv::parameter;
 //]
 
-#include "../test/test.hpp"
-
 static
 void
 example1()
diff --git a/include/boost/convert.hpp b/include/boost/convert.hpp
index 91bb769..d3364d5 100644
--- a/include/boost/convert.hpp
+++ b/include/boost/convert.hpp
@@ -120,7 +120,7 @@ namespace boost
     }
 }
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     template<typename Converter, typename TypeOut, typename TypeIn>
     struct reference
@@ -204,6 +204,6 @@ namespace boost::cnv
     {
         return cnv::reference<Converter, TypeOut, void>(cnv);
     }
-}
+}}
 
 #endif // BOOST_CONVERT_HPP
diff --git a/include/boost/convert/base.hpp b/include/boost/convert/base.hpp
index 163a20a..ccb2e28 100644
--- a/include/boost/convert/base.hpp
+++ b/include/boost/convert/base.hpp
@@ -10,7 +10,7 @@
 #include <algorithm>
 #include <cstring>
 
-namespace boost::cnv { template<typename> struct cnvbase; }
+namespace boost { namespace cnv { template<typename> struct cnvbase; }}
 
 #define BOOST_CNV_TO_STRING                                                 \
     template<typename string_type>                                          \
diff --git a/include/boost/convert/charconv.hpp b/include/boost/convert/charconv.hpp
index 4406969..f2b5713 100644
--- a/include/boost/convert/charconv.hpp
+++ b/include/boost/convert/charconv.hpp
@@ -21,7 +21,7 @@
 #include <charconv>
 #include <type_traits>
 
-namespace boost::cnv { struct charconv; }
+namespace boost { namespace cnv { struct charconv; }}
 
 /// @brief std::to/from_chars-based extended converter
 /// @details The converter offers good overall performance and moderate formatting facilities.
diff --git a/include/boost/convert/detail/char.hpp b/include/boost/convert/detail/char.hpp
index 70980d9..a3d49e4 100644
--- a/include/boost/convert/detail/char.hpp
+++ b/include/boost/convert/detail/char.hpp
@@ -9,7 +9,7 @@
 #include <cctype>
 #include <cwctype>
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     using  char_type = char;
     using uchar_type = unsigned char;
@@ -33,7 +33,7 @@ namespace boost::cnv
     template<> inline  char_type to_upper ( char_type c) { return std::toupper(static_cast<uchar_type>(c)); }
     template<> inline uchar_type to_upper (uchar_type c) { return std::toupper(c); }
     template<> inline wchar_type to_upper (wchar_type c) { return std::towupper(c); }
-}
+}}
 
 #endif // BOOST_CONVERT_DETAIL_IS_CHAR_HPP
 
diff --git a/include/boost/convert/detail/config.hpp b/include/boost/convert/detail/config.hpp
index c2bbfe9..2db671c 100644
--- a/include/boost/convert/detail/config.hpp
+++ b/include/boost/convert/detail/config.hpp
@@ -10,25 +10,25 @@
 #include <boost/optional.hpp>
 #include <type_traits>
 
-#if defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES) || defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
-#undef BOOST_CONVERT_CXX11
+#if defined(BOOST_NO_CXX14)
+#undef BOOST_CONVERT_CXX14
 #else
-#define BOOST_CONVERT_CXX11
+#define BOOST_CONVERT_CXX14
 #endif
 
 // Intel 12.0 and lower have broken SFINAE
 #if defined(BOOST_INTEL) && (BOOST_INTEL <= 1200)
-#   define BOOST_CONVERT_IS_NOT_SUPPORTED
+#undef BOOST_CONVERT_CXX14
 #endif
 
 // No C++11 support
 #if defined(__GNUC__) && (__GNUC__ < 6)
-#   define BOOST_CONVERT_IS_NOT_SUPPORTED
+#undef BOOST_CONVERT_CXX14
 #endif
 
 // MSVC-11 and lower have broken SFINAE
 #if defined(_MSVC_VER) && (_MSVC_VER < 1800)
-#   define BOOST_CONVERT_IS_NOT_SUPPORTED
+#undef BOOST_CONVERT_CXX14
 #endif
 
 #if defined(_MSC_VER)
diff --git a/include/boost/convert/detail/is_callable.hpp b/include/boost/convert/detail/is_callable.hpp
index 972fa92..912eedd 100644
--- a/include/boost/convert/detail/is_callable.hpp
+++ b/include/boost/convert/detail/is_callable.hpp
@@ -7,7 +7,7 @@
 
 #include <boost/convert/detail/has_member.hpp>
 
-namespace boost::cnv::detail
+namespace boost { namespace cnv { namespace detail
 {
     using yes_type = ::boost::type_traits::yes_type;
     using  no_type = ::boost::type_traits:: no_type;
@@ -37,7 +37,7 @@ namespace boost::cnv::detail
         static yes_type test (...);
         static no_type  test (not_found);
     };
-}
+}}}
 
 // No-args case needs to be implemented differently and has not been implemented yet.
 //        template <typename R>
diff --git a/include/boost/convert/detail/is_fun.hpp b/include/boost/convert/detail/is_fun.hpp
index c790f0a..5dabff8 100644
--- a/include/boost/convert/detail/is_fun.hpp
+++ b/include/boost/convert/detail/is_fun.hpp
@@ -11,7 +11,7 @@
 #include <boost/function_types/function_arity.hpp>
 #include <boost/function_types/result_type.hpp>
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     using yes_type = ::boost::type_traits::yes_type;
     using  no_type = ::boost::type_traits:: no_type;
@@ -51,7 +51,7 @@ namespace boost::cnv
 
         BOOST_STATIC_CONSTANT(bool, value = (is_convertible<func_type, out_type>::value));
     };
-}
+}}
 
 #endif // BOOST_CONVERT_IS_FUNCTION_HPP
 
diff --git a/include/boost/convert/detail/is_string.hpp b/include/boost/convert/detail/is_string.hpp
index 95a39ad..161f5a7 100644
--- a/include/boost/convert/detail/is_string.hpp
+++ b/include/boost/convert/detail/is_string.hpp
@@ -7,7 +7,7 @@
 
 #include <boost/convert/detail/range.hpp>
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     namespace detail
     {
@@ -31,6 +31,6 @@ namespace boost::cnv
         typename std::remove_const<T>::type,
         std::is_class<T>::value && cnv::is_range<T>::value>
     {};
-}
+}}
 
 #endif // BOOST_CONVERT_DETAIL_IS_STRING_HPP
diff --git a/include/boost/convert/detail/range.hpp b/include/boost/convert/detail/range.hpp
index 22028df..69da887 100644
--- a/include/boost/convert/detail/range.hpp
+++ b/include/boost/convert/detail/range.hpp
@@ -9,7 +9,7 @@
 #include <boost/convert/detail/char.hpp>
 #include <boost/range/iterator.hpp>
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     namespace detail
     {
@@ -112,6 +112,6 @@ namespace boost::cnv
     {
         range (T* b, T* e =0) : range<T*>(b, e) {}
     };
-}
+}}
 
 #endif // BOOST_CONVERT_DETAIL_RANGE_HPP
diff --git a/include/boost/convert/lexical_cast.hpp b/include/boost/convert/lexical_cast.hpp
index b5076f0..400e16f 100644
--- a/include/boost/convert/lexical_cast.hpp
+++ b/include/boost/convert/lexical_cast.hpp
@@ -7,7 +7,7 @@
 
 #include <boost/lexical_cast.hpp>
 
-namespace boost::cnv { struct lexical_cast; }
+namespace boost { namespace cnv { struct lexical_cast; }}
 
 /// @brief boost::lexical_cast-based converter
 /// @details The purpose of the converter is to
diff --git a/include/boost/convert/parameters.hpp b/include/boost/convert/parameters.hpp
index 57270f6..33a44b2 100644
--- a/include/boost/convert/parameters.hpp
+++ b/include/boost/convert/parameters.hpp
@@ -9,7 +9,7 @@
 #include <boost/parameter/is_argument_pack.hpp>
 #include <boost/mpl/has_key.hpp>
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     enum class   adjust : uint8_t { left, right, center };
     enum class     base : uint8_t { bin =2, oct =8, dec =10, hex =16 };
@@ -28,6 +28,6 @@ namespace boost::cnv
         BOOST_PARAMETER_NAME((lowercase, type) lowercase)
         BOOST_PARAMETER_NAME((    width, type)     width)
     }
-}
+}}
 
 #endif // BOOST_CONVERT_PARAMETERS_HPP
diff --git a/include/boost/convert/printf.hpp b/include/boost/convert/printf.hpp
index c6d89cc..96afa76 100644
--- a/include/boost/convert/printf.hpp
+++ b/include/boost/convert/printf.hpp
@@ -12,7 +12,7 @@
 #include <string>
 #include <cstdio>
 
-namespace boost::cnv { struct printf; }
+namespace boost { namespace cnv { struct printf; }}
 
 struct boost::cnv::printf : boost::cnv::cnvbase<boost::cnv::printf>
 {
diff --git a/include/boost/convert/spirit.hpp b/include/boost/convert/spirit.hpp
index e698c1b..b5fdb2d 100644
--- a/include/boost/convert/spirit.hpp
+++ b/include/boost/convert/spirit.hpp
@@ -10,7 +10,7 @@
 #include <boost/spirit/include/qi.hpp>
 #include <boost/spirit/include/karma.hpp>
 
-namespace boost::cnv { struct spirit; }
+namespace boost { namespace cnv { struct spirit; }}
 
 struct boost::cnv::spirit : boost::cnv::cnvbase<boost::cnv::spirit>
 {
diff --git a/include/boost/convert/stream.hpp b/include/boost/convert/stream.hpp
index 9040c2f..d01e713 100644
--- a/include/boost/convert/stream.hpp
+++ b/include/boost/convert/stream.hpp
@@ -30,13 +30,13 @@
         typename mpl::has_key<              \
             argument_pack, cnv::parameter::type::param_name>::type());
 
-namespace boost::cnv
+namespace boost { namespace cnv
 {
     template<class Char> struct basic_stream;
 
     using cstream = boost::cnv::basic_stream<char>;
     using wstream = boost::cnv::basic_stream<wchar_t>;
-}
+}}
 
 template<class Char>
 struct boost::cnv::basic_stream
diff --git a/include/boost/convert/strtol.hpp b/include/boost/convert/strtol.hpp
index 9f2188b..943eeb6 100644
--- a/include/boost/convert/strtol.hpp
+++ b/include/boost/convert/strtol.hpp
@@ -11,7 +11,7 @@
 #include <climits>
 #include <cstdlib>
 
-namespace boost::cnv { struct strtol; }
+namespace boost { namespace cnv { struct strtol; }}
 
 /// @brief std::strtol-based extended converter
 /// @details The converter offers a fairly decent overall performance and moderate formatting facilities.
diff --git a/test/callable.cpp b/test/callable.cpp
index 0b85e53..9ace54c 100644
--- a/test/callable.cpp
+++ b/test/callable.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/charconv_converter.cpp b/test/charconv_converter.cpp
index 20329cd..bfa2a62 100644
--- a/test/charconv_converter.cpp
+++ b/test/charconv_converter.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED) || defined(BOOST_NO_CXX17_HDR_CHARCONV)
+#if !defined(BOOST_CONVERT_CXX14) || defined(BOOST_NO_CXX17_HDR_CHARCONV)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/encryption.cpp b/test/encryption.cpp
index 19f383e..33db389 100644
--- a/test/encryption.cpp
+++ b/test/encryption.cpp
@@ -4,7 +4,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/fallbacks.cpp b/test/fallbacks.cpp
index cca07d2..8a0bddf 100644
--- a/test/fallbacks.cpp
+++ b/test/fallbacks.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/has_member.cpp b/test/has_member.cpp
index d27bcc6..3492cb3 100644
--- a/test/has_member.cpp
+++ b/test/has_member.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/lcast_converter.cpp b/test/lcast_converter.cpp
index a99ea0c..c70d415 100644
--- a/test/lcast_converter.cpp
+++ b/test/lcast_converter.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/performance.cpp b/test/performance.cpp
index fa30832..d4f5db1 100644
--- a/test/performance.cpp
+++ b/test/performance.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14) || defined(BOOST_NO_CXX17_HDR_CHARCONV)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/performance_spirit.cpp b/test/performance_spirit.cpp
index 3e9b586..2ea7209 100644
--- a/test/performance_spirit.cpp
+++ b/test/performance_spirit.cpp
@@ -9,7 +9,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/printf_converter.cpp b/test/printf_converter.cpp
index 4d4b126..542a6ca 100644
--- a/test/printf_converter.cpp
+++ b/test/printf_converter.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/sfinae.cpp b/test/sfinae.cpp
index c037ef0..c6551ba 100644
--- a/test/sfinae.cpp
+++ b/test/sfinae.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/spirit_converter.cpp b/test/spirit_converter.cpp
index 5bfd48e..6c8b4dc 100644
--- a/test/spirit_converter.cpp
+++ b/test/spirit_converter.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/str_to_int.cpp b/test/str_to_int.cpp
index 447f1f5..8747d72 100644
--- a/test/str_to_int.cpp
+++ b/test/str_to_int.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/stream_converter.cpp b/test/stream_converter.cpp
index a548866..421090a 100644
--- a/test/stream_converter.cpp
+++ b/test/stream_converter.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/strtol_converter.cpp b/test/strtol_converter.cpp
index 054af68..b199f3b 100644
--- a/test/strtol_converter.cpp
+++ b/test/strtol_converter.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else
 
diff --git a/test/test.hpp b/test/test.hpp
index 0d098ae..7e00f1a 100644
--- a/test/test.hpp
+++ b/test/test.hpp
@@ -7,7 +7,7 @@
 
 #include <boost/convert/detail/config.hpp>
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 #else
 
 #include <boost/make_default.hpp>
diff --git a/test/user_type.cpp b/test/user_type.cpp
index f9c357b..f620b71 100644
--- a/test/user_type.cpp
+++ b/test/user_type.cpp
@@ -5,7 +5,7 @@
 
 #include "./test.hpp"
 
-#if defined(BOOST_CONVERT_IS_NOT_SUPPORTED)
+#if !defined(BOOST_CONVERT_CXX14)
 int main(int, char const* []) { return 0; }
 #else