1 2 #ifndef BOOST_MPL_EVAL_IF_HPP_INCLUDED 3 #define BOOST_MPL_EVAL_IF_HPP_INCLUDED 4 5 // Copyright Aleksey Gurtovoy 2000-2004 6 // 7 // Distributed under the Boost Software License, Version 1.0. 8 // (See accompanying file LICENSE_1_0.txt or copy at 9 // http://www.boost.org/LICENSE_1_0.txt) 10 // 11 // See http://www.boost.org/libs/mpl for documentation. 12 13 // $Id: eval_if.hpp 61921 2010-05-11 21:33:24Z neilgroves $ 14 // $Date: 2010-05-11 14:33:24 -0700 (Tue, 11 May 2010) $ 15 // $Revision: 61921 $ 16 17 #include <boost/mpl/if.hpp> 18 #include <boost/mpl/aux_/na_spec.hpp> 19 #include <boost/mpl/aux_/lambda_support.hpp> 20 #include <boost/mpl/aux_/config/msvc.hpp> 21 #include <boost/mpl/aux_/config/gcc.hpp> 22 #include <boost/mpl/aux_/config/workaround.hpp> 23 24 namespace boost { namespace mpl { 25 26 template< 27 typename BOOST_MPL_AUX_NA_PARAM(C) 28 , typename BOOST_MPL_AUX_NA_PARAM(F1) 29 , typename BOOST_MPL_AUX_NA_PARAM(F2) 30 > 31 struct eval_if 32 #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \ 33 || ( BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, >= 0x0300) \ 34 && BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, BOOST_TESTED_AT(0x0304)) \ 35 ) 36 { 37 typedef typename if_<C,F1,F2>::type f_; 38 typedef typename f_::type type; 39 #else 40 : if_<C,F1,F2>::type 41 { 42 #endif 43 BOOST_MPL_AUX_LAMBDA_SUPPORT(3,eval_if,(C,F1,F2)) 44 }; 45 46 // (almost) copy & paste in order to save one more 47 // recursively nested template instantiation to user 48 template< 49 bool C 50 , typename F1 51 , typename F2 52 > 53 struct eval_if_c 54 #if BOOST_WORKAROUND(BOOST_MSVC, <= 1300) \ 55 || ( BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, >= 0x0300) \ 56 && BOOST_WORKAROUND(BOOST_MPL_CFG_GCC, BOOST_TESTED_AT(0x0304)) \ 57 ) 58 { 59 typedef typename if_c<C,F1,F2>::type f_; 60 typedef typename f_::type type; 61 #else 62 : if_c<C,F1,F2>::type 63 { 64 #endif 65 }; 66 67 BOOST_MPL_AUX_NA_SPEC(3, eval_if) 68 69 }} 70 71 #endif // BOOST_MPL_EVAL_IF_HPP_INCLUDED 72