| // Copyright (c) 2001-2011 Hartmut Kaiser |
| // |
| // 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) |
| |
| #if !defined(BOOST_SPIRIT_KARMA_AS_STRING_DEC_18_0644PM) |
| #define BOOST_SPIRIT_KARMA_AS_STRING_DEC_18_0644PM |
| |
| #if defined(_MSC_VER) |
| #pragma once |
| #endif |
| |
| #include <boost/spirit/home/support/unused.hpp> |
| #include <boost/spirit/home/support/attributes_fwd.hpp> |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| namespace boost { namespace spirit { namespace traits |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // This file contains the attribute to string conversion utility. The |
| // utility provided also accept spirit's unused_type; all no-ops. Compiler |
| // optimization will easily strip these away. |
| /////////////////////////////////////////////////////////////////////////// |
| |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename T, typename Attribute> |
| inline typename spirit::result_of::attribute_as<T, Attribute>::type |
| as(Attribute const& attr) |
| { |
| return attribute_as<T, Attribute>::call(attr); |
| } |
| |
| template <typename T> |
| inline unused_type as(unused_type) |
| { |
| return unused; |
| } |
| |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename T, typename Attribute> |
| inline bool valid_as(Attribute const& attr) |
| { |
| return attribute_as<T, Attribute>::is_valid(attr); |
| } |
| |
| template <typename T> |
| inline bool valid_as(unused_type) |
| { |
| return true; |
| } |
| }}} |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| namespace boost { namespace spirit { namespace result_of |
| { |
| template <typename T, typename Attribute> |
| struct attribute_as |
| : traits::attribute_as<T, Attribute> |
| {}; |
| |
| template <typename T> |
| struct attribute_as<T, unused_type> |
| { |
| typedef unused_type type; |
| }; |
| |
| template <typename T> |
| struct attribute_as<T, unused_type const> |
| { |
| typedef unused_type type; |
| }; |
| }}} |
| |
| #endif |