sl@0: // Copyright David Abrahams 2005. Distributed under the Boost
sl@0: // Software License, Version 1.0. (See accompanying
sl@0: // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
sl@0: #ifndef BOOST_PARAMETER_BINDING_DWA200558_HPP
sl@0: # define BOOST_PARAMETER_BINDING_DWA200558_HPP
sl@0: 
sl@0: # include <boost/mpl/apply.hpp>
sl@0: # include <boost/mpl/assert.hpp>
sl@0: # include <boost/mpl/and.hpp>
sl@0: # include <boost/parameter/aux_/result_of0.hpp>
sl@0: # include <boost/parameter/aux_/void.hpp>
sl@0: # include <boost/type_traits/is_same.hpp>
sl@0: 
sl@0: # if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
sl@0: #  include <boost/mpl/eval_if.hpp>
sl@0: # endif
sl@0: 
sl@0: namespace boost { namespace parameter { 
sl@0: 
sl@0: // A metafunction that, given an argument pack, returns the type of
sl@0: // the parameter identified by the given keyword.  If no such
sl@0: // parameter has been specified, returns Default
sl@0: 
sl@0: # if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \
sl@0:   || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
sl@0: template <class Parameters, class Keyword, class Default>
sl@0: struct binding0
sl@0: {
sl@0:     typedef typename mpl::apply_wrap3<
sl@0:         typename Parameters::binding,Keyword,Default,mpl::true_
sl@0:     >::type type;
sl@0: 
sl@0:     BOOST_MPL_ASSERT_NOT((
sl@0:         mpl::and_<
sl@0:             is_same<Default, void_>
sl@0:           , is_same<type, void_>
sl@0:         >
sl@0:     ));
sl@0: };
sl@0: # endif
sl@0: 
sl@0: template <class Parameters, class Keyword, class Default = void_>
sl@0: # if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
sl@0: struct binding
sl@0: # else
sl@0: struct binding_eti
sl@0: # endif
sl@0: {
sl@0: # if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \
sl@0:   || BOOST_WORKAROUND(__BORLANDC__, BOOST_TESTED_AT(0x564))
sl@0:     typedef typename mpl::eval_if<
sl@0:         mpl::is_placeholder<Parameters>
sl@0:       , mpl::identity<int>
sl@0:       , binding0<Parameters,Keyword,Default>
sl@0:     >::type type;
sl@0: # else
sl@0:     typedef typename mpl::apply_wrap3<
sl@0:         typename Parameters::binding,Keyword,Default,mpl::true_
sl@0:     >::type type;
sl@0: 
sl@0:     BOOST_MPL_ASSERT_NOT((
sl@0:         mpl::and_<
sl@0:             is_same<Default, void_>
sl@0:           , is_same<type, void_>
sl@0:         >
sl@0:     ));
sl@0: # endif
sl@0: 
sl@0: # if !BOOST_WORKAROUND(BOOST_MSVC, < 1300)
sl@0:     BOOST_MPL_AUX_LAMBDA_SUPPORT(3,binding,(Parameters,Keyword,Default))
sl@0: # endif
sl@0: };
sl@0: 
sl@0: # if BOOST_WORKAROUND(BOOST_MSVC, < 1300)
sl@0: template <class Parameters, class Keyword, class Default = void_>
sl@0: struct binding
sl@0: {
sl@0:     typedef typename mpl::eval_if<
sl@0:         is_same<Parameters, int>
sl@0:       , mpl::identity<int>
sl@0:       , binding_eti<Parameters, Keyword, Default>
sl@0:     >::type type;
sl@0: 
sl@0:     BOOST_MPL_AUX_LAMBDA_SUPPORT(3,binding,(Parameters,Keyword,Default))
sl@0: };
sl@0: # endif
sl@0: 
sl@0: // A metafunction that, given an argument pack, returns the type of
sl@0: // the parameter identified by the given keyword.  If no such
sl@0: // parameter has been specified, returns the type returned by invoking
sl@0: // DefaultFn
sl@0: template <class Parameters, class Keyword, class DefaultFn>
sl@0: struct lazy_binding
sl@0: {
sl@0:   typedef typename mpl::apply_wrap3<
sl@0:       typename Parameters::binding
sl@0:     , Keyword
sl@0:     , typename aux::result_of0<DefaultFn>::type
sl@0:     , mpl::true_
sl@0:   >::type type;
sl@0: };
sl@0: 
sl@0: 
sl@0: }} // namespace boost::parameter
sl@0: 
sl@0: #endif // BOOST_PARAMETER_BINDING_DWA200558_HPP