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Diffstat (limited to 'boost/metaparse/v1/always.hpp')
-rw-r--r-- | boost/metaparse/v1/always.hpp | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/boost/metaparse/v1/always.hpp b/boost/metaparse/v1/always.hpp new file mode 100644 index 0000000000..0a10ff4573 --- /dev/null +++ b/boost/metaparse/v1/always.hpp @@ -0,0 +1,51 @@ +#ifndef BOOST_METAPARSE_V1_ALWAYS_HPP +#define BOOST_METAPARSE_V1_ALWAYS_HPP + +// Copyright Abel Sinkovics (abel@sinkovics.hu) 2009 - 2010. +// 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) + +#include <boost/metaparse/v1/accept.hpp> +#include <boost/metaparse/v1/is_error.hpp> +#include <boost/metaparse/v1/get_remaining.hpp> +#include <boost/metaparse/v1/get_position.hpp> + +#include <boost/mpl/eval_if.hpp> + +namespace boost +{ + namespace metaparse + { + namespace v1 + { + template <class P, class Result> + struct always + { + private: + template <class Res> + struct apply_unchecked : + accept< + Result, + typename get_remaining<Res>::type, + typename get_position<Res>::type + > + {}; + public: + typedef always type; + + template <class S, class Pos> + struct apply : + boost::mpl::eval_if< + typename is_error<typename P::template apply<S, Pos> >::type, + typename P::template apply<S, Pos>, + apply_unchecked<typename P::template apply<S, Pos> > + > + {}; + }; + } + } +} + +#endif + |