ext-boost/boost/mpl/aux_/O1_size_impl.hpp
2014-12-07 23:50:51 +01:00

88 lines
2.1 KiB
C++

#ifndef BOOST_MPL_O1_SIZE_IMPL_HPP_INCLUDED
#define BOOST_MPL_O1_SIZE_IMPL_HPP_INCLUDED
// Copyright Aleksey Gurtovoy 2000-2004
//
// 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)
//
// See http://www.boost.org/libs/mpl for documentation.
// $Id$
// $Date$
// $Revision$
#include <boost/mpl/O1_size_fwd.hpp>
#include <boost/mpl/long.hpp>
#include <boost/mpl/if.hpp>
#include <boost/mpl/aux_/has_size.hpp>
#include <boost/mpl/aux_/config/forwarding.hpp>
#include <boost/mpl/aux_/config/static_constant.hpp>
#include <boost/mpl/aux_/config/msvc.hpp>
#include <boost/mpl/aux_/config/workaround.hpp>
namespace boost { namespace mpl {
// default implementation - returns 'Sequence::size' if sequence has a 'size'
// member, and -1 otherwise; conrete sequences might override it by
// specializing either the 'O1_size_impl' or the primary 'O1_size' template
# if !BOOST_WORKAROUND(BOOST_MSVC, < 1300) \
&& !BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3003))
namespace aux {
template< typename Sequence > struct O1_size_impl
: Sequence::size
{
};
}
template< typename Tag >
struct O1_size_impl
{
template< typename Sequence > struct apply
#if !defined(BOOST_MPL_CFG_NO_NESTED_FORWARDING)
: if_<
aux::has_size<Sequence>
, aux::O1_size_impl<Sequence>
, long_<-1>
>::type
{
#else
{
typedef typename if_<
aux::has_size<Sequence>
, aux::O1_size_impl<Sequence>
, long_<-1>
>::type type;
BOOST_STATIC_CONSTANT(long, value =
(if_<
aux::has_size<Sequence>
, aux::O1_size_impl<Sequence>
, long_<-1>
>::type::value)
);
#endif
};
};
# else // BOOST_MSVC
template< typename Tag >
struct O1_size_impl
{
template< typename Sequence > struct apply
: long_<-1>
{
};
};
# endif
}}
#endif // BOOST_MPL_O1_SIZE_IMPL_HPP_INCLUDED