// Copyright Aleksey Gurtovoy 2002-2006
// Copyright David Abrahams 2002-2003
+// Copyright Daniel Walker 2007
//
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
//
// See http://www.boost.org/libs/mpl for documentation.
-// $Id: has_xxx.hpp 49273 2008-10-11 06:54:06Z agurtovoy $
-// $Date: 2008-10-11 02:54:06 -0400 (Sat, 11 Oct 2008) $
-// $Revision: 49273 $
+// $Id: has_xxx.hpp 64146 2010-07-19 00:46:31Z djwalker $
+// $Date: 2010-07-18 20:46:31 -0400 (Sun, 18 Jul 2010) $
+// $Revision: 64146 $
#include <boost/mpl/bool.hpp>
+#include <boost/mpl/aux_/na_spec.hpp>
#include <boost/mpl/aux_/type_wrapper.hpp>
#include <boost/mpl/aux_/yes_no.hpp>
+#include <boost/mpl/aux_/config/gcc.hpp>
#include <boost/mpl/aux_/config/has_xxx.hpp>
#include <boost/mpl/aux_/config/msvc_typename.hpp>
#include <boost/mpl/aux_/config/msvc.hpp>
#include <boost/mpl/aux_/config/static_constant.hpp>
#include <boost/mpl/aux_/config/workaround.hpp>
+#include <boost/preprocessor/array/elem.hpp>
#include <boost/preprocessor/cat.hpp>
+#include <boost/preprocessor/control/if.hpp>
+#include <boost/preprocessor/repetition/enum_params.hpp>
+#include <boost/preprocessor/repetition/enum_trailing_params.hpp>
#if BOOST_WORKAROUND( __BORLANDC__, BOOST_TESTED_AT(0x590) )
# include <boost/type_traits/is_class.hpp>
BOOST_MPL_HAS_XXX_TRAIT_NAMED_DEF(BOOST_PP_CAT(has_,name), name, false) \
/**/
+
+#if !defined(BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE)
+
+// Create a boolean Metafunction to detect a nested template
+// member. This implementation is based on a USENET newsgroup's
+// posting by Aleksey Gurtovoy (comp.lang.c++.moderated, 2002-03-19),
+// Rani Sharoni's USENET posting cited above, the non-template has_xxx
+// implementations above, and discussion on the Boost mailing list.
+
+# if !defined(BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES)
+# if BOOST_WORKAROUND(BOOST_MSVC, <= 1400)
+# define BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES 1
+# endif
+# endif
+
+# if !defined(BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION)
+# if (defined(BOOST_NO_EXPLICIT_FUNCTION_TEMPLATE_ARGUMENTS))
+# define BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION 1
+# endif
+# endif
+
+# if !defined(BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE)
+# if BOOST_WORKAROUND(BOOST_MSVC, <= 1400)
+# define BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE 1
+# endif
+# endif
+
+// NOTE: Many internal implementation macros take a Boost.Preprocessor
+// array argument called args which is of the following form.
+// ( 4, ( trait, name, max_arity, default_ ) )
+
+# define BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args) \
+ BOOST_PP_CAT(BOOST_PP_ARRAY_ELEM(0, args) , _introspect) \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) \
+ BOOST_PP_CAT(BOOST_PP_CAT(BOOST_PP_ARRAY_ELEM(0, args) , _substitute), n) \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args) \
+ BOOST_PP_CAT(BOOST_PP_ARRAY_ELEM(0, args) , _test) \
+ /**/
+
+// Thanks to Guillaume Melquiond for pointing out the need for the
+// "substitute" template as an argument to the overloaded test
+// functions to get SFINAE to work for member templates with the
+// correct name but different number of arguments.
+# define BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE(z, n, args) \
+ template< \
+ template< BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(n), typename V) > class V \
+ > \
+ struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) { \
+ }; \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_SUBSTITUTE(args, substitute_macro) \
+ BOOST_PP_REPEAT( \
+ BOOST_PP_ARRAY_ELEM(2, args) \
+ , BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE \
+ , args \
+ ) \
+ /**/
+
+# if !BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION
+# define BOOST_MPL_HAS_MEMBER_REJECT(args, member_macro) \
+ template< typename V > \
+ static boost::mpl::aux::no_tag \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)(...); \
+ /**/
+# else
+# define BOOST_MPL_HAS_MEMBER_REJECT(args, member_macro) \
+ static boost::mpl::aux::no_tag \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)(...); \
+ /**/
+# endif
+
+# if !BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES
+# define BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT(z, n, args) \
+ template< typename V > \
+ static boost::mpl::aux::yes_tag \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \
+ boost::mpl::aux::type_wrapper< V > const volatile* \
+ , BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) < \
+ V::template BOOST_PP_ARRAY_ELEM(1, args) \
+ >* = 0 \
+ ); \
+ /**/
+# define BOOST_MPL_HAS_MEMBER_ACCEPT(args, member_macro) \
+ BOOST_PP_REPEAT( \
+ BOOST_PP_ARRAY_ELEM(2, args) \
+ , BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT \
+ , args \
+ ) \
+ /**/
+# else
+# define BOOST_MPL_HAS_MEMBER_ACCEPT(args, member_macro) \
+ template< typename V > \
+ static boost::mpl::aux::yes_tag \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \
+ V const volatile* \
+ , member_macro(args, V, T)* = 0 \
+ ); \
+ /**/
+# endif
+
+# if !BOOST_MPL_HAS_XXX_NO_EXPLICIT_TEST_FUNCTION
+# define BOOST_MPL_HAS_MEMBER_TEST(args) \
+ sizeof(BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)< U >(0)) \
+ == sizeof(boost::mpl::aux::yes_tag) \
+ /**/
+# else
+# if !BOOST_MPL_HAS_XXX_NO_WRAPPED_TYPES
+# define BOOST_MPL_HAS_MEMBER_TEST(args) \
+ sizeof( \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \
+ static_cast< boost::mpl::aux::type_wrapper< U >* >(0) \
+ ) \
+ ) == sizeof(boost::mpl::aux::yes_tag) \
+ /**/
+# else
+# define BOOST_MPL_HAS_MEMBER_TEST(args) \
+ sizeof( \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)( \
+ static_cast< U* >(0) \
+ ) \
+ ) == sizeof(boost::mpl::aux::yes_tag) \
+ /**/
+# endif
+# endif
+
+# define BOOST_MPL_HAS_MEMBER_INTROSPECT( \
+ args, substitute_macro, member_macro \
+ ) \
+ template< typename U > \
+ struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args) { \
+ BOOST_MPL_HAS_MEMBER_SUBSTITUTE(args, substitute_macro) \
+ BOOST_MPL_HAS_MEMBER_REJECT(args, member_macro) \
+ BOOST_MPL_HAS_MEMBER_ACCEPT(args, member_macro) \
+ BOOST_STATIC_CONSTANT( \
+ bool, value = BOOST_MPL_HAS_MEMBER_TEST(args) \
+ ); \
+ typedef boost::mpl::bool_< value > type; \
+ }; \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_IMPLEMENTATION( \
+ args, introspect_macro, substitute_macro, member_macro \
+ ) \
+ template< \
+ typename T \
+ , typename fallback_ \
+ = boost::mpl::bool_< BOOST_PP_ARRAY_ELEM(3, args) > \
+ > \
+ class BOOST_PP_ARRAY_ELEM(0, args) { \
+ introspect_macro(args, substitute_macro, member_macro) \
+ public: \
+ static const bool value \
+ = BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args)< T >::value; \
+ typedef typename BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args)< \
+ T \
+ >::type type; \
+ }; \
+ /**/
+
+// BOOST_MPL_HAS_MEMBER_WITH_FUNCTION_SFINAE expands to the full
+// implementation of the function-based metafunction. Compile with -E
+// to see the preprocessor output for this macro.
+# define BOOST_MPL_HAS_MEMBER_WITH_FUNCTION_SFINAE( \
+ args, substitute_macro, member_macro \
+ ) \
+ BOOST_MPL_HAS_MEMBER_IMPLEMENTATION( \
+ args \
+ , BOOST_MPL_HAS_MEMBER_INTROSPECT \
+ , substitute_macro \
+ , member_macro \
+ ) \
+ /**/
+
+# if BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE
+
+# if !defined(BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE)
+# if BOOST_WORKAROUND(BOOST_MSVC, <= 1400)
+# define BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE 1
+# endif
+# endif
+
+# if !BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE
+# define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \
+ args, n \
+ ) \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) \
+ /**/
+# else
+# define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \
+ args, n \
+ ) \
+ BOOST_PP_CAT( \
+ boost_mpl_has_xxx_ \
+ , BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME(args, n) \
+ ) \
+ /**/
+# endif
+
+# define BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME( \
+ args \
+ ) \
+ BOOST_PP_CAT( \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \
+ args, 0 \
+ ) \
+ , _tag \
+ ) \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE_WITH_TEMPLATE_SFINAE( \
+ z, n, args \
+ ) \
+ template< \
+ template< BOOST_PP_ENUM_PARAMS(BOOST_PP_INC(n), typename U) > class U \
+ > \
+ struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \
+ args, n \
+ ) { \
+ typedef \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME(args) \
+ type; \
+ }; \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_SUBSTITUTE_WITH_TEMPLATE_SFINAE( \
+ args, substitute_macro \
+ ) \
+ typedef void \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME(args); \
+ BOOST_PP_REPEAT( \
+ BOOST_PP_ARRAY_ELEM(2, args) \
+ , BOOST_MPL_HAS_MEMBER_MULTI_SUBSTITUTE_WITH_TEMPLATE_SFINAE \
+ , args \
+ ) \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_REJECT_WITH_TEMPLATE_SFINAE( \
+ args, member_macro \
+ ) \
+ template< \
+ typename U \
+ , typename V \
+ = BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_TAG_NAME(args) \
+ > \
+ struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args) { \
+ BOOST_STATIC_CONSTANT(bool, value = false); \
+ typedef boost::mpl::bool_< value > type; \
+ }; \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT_WITH_TEMPLATE_SFINAE( \
+ z, n, args \
+ ) \
+ template< typename U > \
+ struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)< \
+ U \
+ , typename \
+ BOOST_MPL_HAS_MEMBER_INTROSPECTION_SUBSTITUTE_NAME_WITH_TEMPLATE_SFINAE( \
+ args, n \
+ )< \
+ BOOST_MSVC_TYPENAME U::BOOST_PP_ARRAY_ELEM(1, args)< > \
+ >::type \
+ > { \
+ BOOST_STATIC_CONSTANT(bool, value = true); \
+ typedef boost::mpl::bool_< value > type; \
+ }; \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_ACCEPT_WITH_TEMPLATE_SFINAE( \
+ args, member_macro \
+ ) \
+ BOOST_PP_REPEAT( \
+ BOOST_PP_ARRAY_ELEM(2, args) \
+ , BOOST_MPL_HAS_MEMBER_MULTI_ACCEPT_WITH_TEMPLATE_SFINAE \
+ , args \
+ ) \
+ /**/
+
+# define BOOST_MPL_HAS_MEMBER_INTROSPECT_WITH_TEMPLATE_SFINAE( \
+ args, substitute_macro, member_macro \
+ ) \
+ BOOST_MPL_HAS_MEMBER_REJECT_WITH_TEMPLATE_SFINAE(args, member_macro) \
+ BOOST_MPL_HAS_MEMBER_ACCEPT_WITH_TEMPLATE_SFINAE(args, member_macro) \
+ template< typename U > \
+ struct BOOST_MPL_HAS_MEMBER_INTROSPECTION_NAME(args) \
+ : BOOST_MPL_HAS_MEMBER_INTROSPECTION_TEST_NAME(args)< U > { \
+ }; \
+ /**/
+
+// BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE expands to the full
+// implementation of the template-based metafunction. Compile with -E
+// to see the preprocessor output for this macro.
+//
+// Note that if BOOST_MPL_HAS_XXX_NEEDS_NAMESPACE_LEVEL_SUBSTITUTE is
+// defined BOOST_MPL_HAS_MEMBER_SUBSTITUTE_WITH_TEMPLATE_SFINAE needs
+// to be expanded at namespace level before
+// BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE can be used.
+# define BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE( \
+ args, substitute_macro, member_macro \
+ ) \
+ BOOST_MPL_HAS_MEMBER_SUBSTITUTE_WITH_TEMPLATE_SFINAE( \
+ args, substitute_macro \
+ ) \
+ BOOST_MPL_HAS_MEMBER_IMPLEMENTATION( \
+ args \
+ , BOOST_MPL_HAS_MEMBER_INTROSPECT_WITH_TEMPLATE_SFINAE \
+ , substitute_macro \
+ , member_macro \
+ ) \
+ /**/
+
+# endif // BOOST_MPL_HAS_XXX_NEEDS_TEMPLATE_SFINAE
+
+// Note: In the current implementation the parameter and access macros
+// are no longer expanded.
+# if !BOOST_WORKAROUND(BOOST_MSVC, <= 1400)
+# define BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF(trait, name, default_) \
+ BOOST_MPL_HAS_MEMBER_WITH_FUNCTION_SFINAE( \
+ ( 4, ( trait, name, BOOST_MPL_LIMIT_METAFUNCTION_ARITY, default_ ) ) \
+ , BOOST_MPL_HAS_MEMBER_TEMPLATE_SUBSTITUTE_PARAMETER \
+ , BOOST_MPL_HAS_MEMBER_TEMPLATE_ACCESS \
+ ) \
+ /**/
+# else
+# define BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF(trait, name, default_) \
+ BOOST_MPL_HAS_MEMBER_WITH_TEMPLATE_SFINAE( \
+ ( 4, ( trait, name, BOOST_MPL_LIMIT_METAFUNCTION_ARITY, default_ ) ) \
+ , BOOST_MPL_HAS_MEMBER_TEMPLATE_SUBSTITUTE_PARAMETER \
+ , BOOST_MPL_HAS_MEMBER_TEMPLATE_ACCESS \
+ ) \
+ /**/
+# endif
+
+#else // BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE
+
+// placeholder implementation
+
+# define BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF(trait, name, default_) \
+ template< typename T \
+ , typename fallback_ = boost::mpl::bool_< default_ > > \
+ struct trait { \
+ BOOST_STATIC_CONSTANT(bool, value = fallback_::value); \
+ typedef fallback_ type; \
+ }; \
+ /**/
+
+#endif // BOOST_MPL_CFG_NO_HAS_XXX_TEMPLATE
+
+# define BOOST_MPL_HAS_XXX_TEMPLATE_DEF(name) \
+ BOOST_MPL_HAS_XXX_TEMPLATE_NAMED_DEF( \
+ BOOST_PP_CAT(has_, name), name, false \
+ ) \
+ /**/
+
#endif // BOOST_MPL_HAS_XXX_HPP_INCLUDED