| /*============================================================================= | |
| 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 |