refactor: make talon's choice of result message easier to read in the code as per Richard's suggestion.
#ifndef BOOST_MPL_EVAL_IF_HPP_INCLUDED
#define BOOST_MPL_EVAL_IF_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: eval_if.hpp 49267 2008-10-11 06:19:02Z agurtovoy $
// $Date: 2008-10-11 02:19:02 -0400 (Sat, 11 Oct 2008) $
// $Revision: 49267 $
#include <boost/mpl/if.hpp>
#include <boost/mpl/aux_/na_spec.hpp>
#include <boost/mpl/aux_/lambda_support.hpp>
#include <boost/mpl/aux_/config/msvc.hpp>
#include <boost/mpl/aux_/config/gcc.hpp>
#include <boost/mpl/aux_/config/workaround.hpp>
namespace boost { namespace mpl {
template<
typename BOOST_MPL_AUX_NA_PARAM(C)
, typename BOOST_MPL_AUX_NA_PARAM(F1)
, typename BOOST_MPL_AUX_NA_PARAM(F2)
>
struct eval_if
#if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \
|| ( BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, >= 0x0300) \
&& BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, BOOST_TESTED_AT(0x0304)) \
)
{
typedef typename if_<C,F1,F2>::type f_;
typedef typename f_::type type;
#else
: if_<C,F1,F2>::type
{
#endif
BOOST_MPL_AUX_LAMBDA_SUPPORT(3,eval_if,(C,F1,F2))
};
// (almost) copy & paste in order to save one more
// recursively nested template instantiation to user
template<
bool C
, typename F1
, typename F2
>
struct eval_if_c
#if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \
|| ( BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, >= 0x0300) \
&& BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, BOOST_TESTED_AT(0x0304)) \
)
{
typedef typename if_c<C,F1,F2>::type f_;
typedef typename f_::type type;
#else
: if_c<C,F1,F2>::type
{
#endif
};
BOOST_MPL_AUX_NA_SPEC(3, eval_if)
}}
#endif // BOOST_MPL_EVAL_IF_HPP_INCLUDED