| /*============================================================================= |
| Copyright (c) 2001-2003 Daniel Nuffer |
| http://spirit.sourceforge.net/ |
| |
| 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) |
| =============================================================================*/ |
| #ifndef BOOST_SPIRIT_FLUSH_MULTI_PASS_HPP |
| #define BOOST_SPIRIT_FLUSH_MULTI_PASS_HPP |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| #include <boost/spirit/home/classic/namespace.hpp> |
| #include <boost/spirit/home/classic/core.hpp> |
| #include <boost/spirit/home/classic/iterator/multi_pass.hpp> |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| namespace boost { namespace spirit { |
| |
| BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN |
| |
| namespace impl { |
| |
| template <typename T> |
| void flush_iterator(T &) {} |
| |
| template <typename T1, typename T2, typename T3, typename T4> |
| void flush_iterator(BOOST_SPIRIT_CLASSIC_NS::multi_pass< |
| T1, T2, T3, T4, BOOST_SPIRIT_CLASSIC_NS::multi_pass_policies::std_deque> &i) |
| { |
| i.clear_queue(); |
| } |
| |
| } // namespace impl |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // |
| // flush_multi_pass_parser |
| // |
| // The flush_multi_pass_parser flushes an underlying |
| // multi_pass_iterator during the normal parsing process. This may |
| // be used at certain points during the parsing process, when it is |
| // clear, that no backtracking is needed anymore and the input |
| // gathered so far may be discarded. |
| // |
| /////////////////////////////////////////////////////////////////////////// |
| class flush_multi_pass_parser |
| : public parser<flush_multi_pass_parser> |
| { |
| public: |
| typedef flush_multi_pass_parser this_t; |
| |
| template <typename ScannerT> |
| typename parser_result<this_t, ScannerT>::type |
| parse(ScannerT const& scan) const |
| { |
| impl::flush_iterator(scan.first); |
| return scan.empty_match(); |
| } |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // |
| // predefined flush_multi_pass_p object |
| // |
| // This object should may used to flush a multi_pass_iterator along |
| // the way during the normal parsing process. |
| // |
| /////////////////////////////////////////////////////////////////////////// |
| |
| flush_multi_pass_parser const |
| flush_multi_pass_p = flush_multi_pass_parser(); |
| |
| BOOST_SPIRIT_CLASSIC_NAMESPACE_END |
| |
| }} // namespace BOOST_SPIRIT_CLASSIC_NS |
| |
| #endif // BOOST_SPIRIT_FLUSH_MULTI_PASS_HPP |