Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

boost/predef/language.h

/*
Copyright Rene Rivera 2011-2015
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)
*/

#if !defined(BOOST_PREDEF_LANGUAGE_H) || defined(BOOST_PREDEF_INTERNAL_GENERATE_TESTS)
#ifndef BOOST_PREDEF_LANGUAGE_H
#define BOOST_PREDEF_LANGUAGE_H
#endif

#include <boost/predef/language/stdc.h>
#include <boost/predef/language/stdcpp.h>
#include <boost/predef/language/objc.h>
#include <boost/predef/language/cuda.h>

#endif