Squashed 'third_party/boostorg/concept_check/' content from commit ed0a0eb
Change-Id: Ib7230965334f9501601efc300242efde8352a380
git-subtree-dir: third_party/boostorg/concept_check
git-subtree-split: ed0a0ebd72f778cfa4931e0538ea34c28db3a42b
diff --git a/include/boost/concept/requires.hpp b/include/boost/concept/requires.hpp
new file mode 100644
index 0000000..365ce10
--- /dev/null
+++ b/include/boost/concept/requires.hpp
@@ -0,0 +1,93 @@
+// Copyright David Abrahams 2006. 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)
+#ifndef BOOST_CONCEPT_REQUIRES_DWA2006430_HPP
+# define BOOST_CONCEPT_REQUIRES_DWA2006430_HPP
+
+# include <boost/config.hpp>
+# include <boost/concept/assert.hpp>
+# include <boost/preprocessor/seq/for_each.hpp>
+
+namespace boost {
+
+// unaryfunptr_arg_type from parameter/aux_/parenthesized_type.hpp
+
+namespace ccheck_aux {
+
+// A metafunction that transforms void(*)(T) -> T
+template <class UnaryFunctionPointer>
+struct unaryfunptr_arg_type;
+
+template <class Arg>
+struct unaryfunptr_arg_type<void(*)(Arg)>
+{
+ typedef Arg type;
+};
+
+template <>
+struct unaryfunptr_arg_type<void(*)(void)>
+{
+ typedef void type;
+};
+
+} // namespace ccheck_aux
+
+// Template for use in handwritten assertions
+template <class Model, class More>
+struct requires_ : More
+{
+ BOOST_CONCEPT_ASSERT((Model));
+};
+
+// Template for use by macros, where models must be wrapped in parens.
+// This isn't in namespace detail to keep extra cruft out of resulting
+// error messages.
+template <class ModelFn>
+struct _requires_
+{
+ enum { value = 0 };
+ BOOST_CONCEPT_ASSERT_FN(ModelFn);
+};
+
+template <int check, class Result>
+struct Requires_ : ::boost::ccheck_aux::unaryfunptr_arg_type<Result>
+{
+};
+
+# if BOOST_WORKAROUND(BOOST_INTEL_WIN, BOOST_TESTED_AT(1010))
+# define BOOST_CONCEPT_REQUIRES_(r,data,t) | (::boost::_requires_<void(*)t>::value)
+# else
+# define BOOST_CONCEPT_REQUIRES_(r,data,t) + (::boost::_requires_<void(*)t>::value)
+# endif
+
+#if defined(NDEBUG)
+
+# define BOOST_CONCEPT_REQUIRES(models, result) \
+ typename ::boost::ccheck_aux::unaryfunptr_arg_type<void(*)result>::type
+
+#elif BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
+
+// Same thing as below without the initial typename
+# define BOOST_CONCEPT_REQUIRES(models, result) \
+ ::boost::Requires_< \
+ (0 BOOST_PP_SEQ_FOR_EACH(BOOST_CONCEPT_REQUIRES_, ~, models)), \
+ ::boost::ccheck_aux::unaryfunptr_arg_type<void(*)result> \
+ >::type
+
+#else
+
+// This just ICEs on MSVC6 :(
+# define BOOST_CONCEPT_REQUIRES(models, result) \
+ typename ::boost::Requires_< \
+ (0 BOOST_PP_SEQ_FOR_EACH(BOOST_CONCEPT_REQUIRES_, ~, models)), \
+ void(*)result \
+ >::type
+
+#endif
+
+// C++0x proposed syntax changed. This supports an older usage
+#define BOOST_CONCEPT_WHERE(models,result) BOOST_CONCEPT_REQUIRES(models,result)
+
+} // namespace boost::concept_check
+
+#endif // BOOST_CONCEPT_REQUIRES_DWA2006430_HPP