boost/bind/arg.hpp

0001 #ifndef BOOST_BIND_ARG_HPP_INCLUDED
0002 #define BOOST_BIND_ARG_HPP_INCLUDED
0003
0004 // MS compatible compilers support #pragma once
0005
0006 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
0007 # pragma once
0008 #endif
0009
0010 //
0011 //  bind/arg.hpp
0012 //
0013 //  Copyright (c) 2002 Peter Dimov and Multi Media Ltd.
0014 //
0015 // Distributed under the Boost Software License, Version 1.0. (See
0016 // accompanying file LICENSE_1_0.txt or copy at
0017 // http://www.boost.org/LICENSE_1_0.txt)
0018 //
0019 //  See http://www.boost.org/libs/bind/bind.html for documentation.
0020 //
0021
0022 #include <boost/config.hpp>
0023 #include <boost/is_placeholder.hpp>
0024
0025 namespace boost
0026 {
0027
0028 template<bool Eq> struct _arg_eq
0029 {
0030 };
0031
0032 template<> struct _arg_eq<true>
0033 {
0034     typedef void type;
0035 };
0036
0037 template< int I > struct arg
0038 {
0039     BOOST_CONSTEXPR arg()
0040     {
0041     }
0042
0043     template< class T > BOOST_CONSTEXPR arg( T const & /* t */, typename _arg_eq< I == is_placeholder<T>::value >::type * = 0 )
0044     {
0045     }
0046 };
0047
0048 template< int I > BOOST_CONSTEXPR bool operator==( arg<I> const &, arg<I> const & )
0049 {
0050     return true;
0051 }
0052
0053 #if !defined( BOOST_NO_TEMPLATE_PARTIAL_SPECIALIZATION )
0054
0055 template< int I > struct is_placeholder< arg<I> >
0056 {
0057     enum _vt { value = I };
0058 };
0059
0060 template< int I > struct is_placeholder< arg<I> (*) () >
0061 {
0062     enum _vt { value = I };
0063 };
0064
0065 #endif
0066
0067 } // namespace boost
0068
0069 #endif // #ifndef BOOST_BIND_ARG_HPP_INCLUDED