1 /*============================================================================= 2 Copyright (c) 1998-2003 Joel de Guzman 3 Copyright (c) 2001 Daniel Nuffer 4 Copyright (c) 2002 Hartmut Kaiser 5 http://spirit.sourceforge.net/ 6 7 Distributed under the Boost Software License, Version 1.0. (See accompanying 8 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 9 =============================================================================*/ 10 #if !defined(BOOST_SPIRIT_POSITIVE_HPP) 11 #define BOOST_SPIRIT_POSITIVE_HPP 12 13 #include <boost/spirit/home/classic/namespace.hpp> 14 #include <boost/spirit/home/classic/core/parser.hpp> 15 #include <boost/spirit/home/classic/core/primitives/primitives.hpp> 16 #include <boost/spirit/home/classic/core/composite/composite.hpp> 17 #include <boost/spirit/home/classic/meta/as_parser.hpp> 18 19 namespace boost { namespace spirit { 20 21 BOOST_SPIRIT_CLASSIC_NAMESPACE_BEGIN 22 23 /////////////////////////////////////////////////////////////////////////// 24 // 25 // positive class 26 // 27 // Handles expressions of the form: 28 // 29 // +a 30 // 31 // where a is a parser. The expression returns a composite 32 // parser that matches its subject one (1) or more times. 33 // 34 /////////////////////////////////////////////////////////////////////////// 35 struct positive_parser_gen; 36 37 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) 38 #pragma warning(push) 39 #pragma warning(disable:4512) //assignment operator could not be generated 40 #endif 41 42 template <typename S> 43 struct positive 44 : public unary<S, parser<positive<S> > > 45 { 46 typedef positive<S> self_t; 47 typedef unary_parser_category parser_category_t; 48 typedef positive_parser_gen parser_generator_t; 49 typedef unary<S, parser<self_t> > base_t; 50 positiveboost::spirit::positive51 positive(S const& a) 52 : base_t(a) {} 53 54 template <typename ScannerT> 55 typename parser_result<self_t, ScannerT>::type parseboost::spirit::positive56 parse(ScannerT const& scan) const 57 { 58 typedef typename parser_result<self_t, ScannerT>::type result_t; 59 typedef typename ScannerT::iterator_t iterator_t; 60 result_t hit = this->subject().parse(scan); 61 62 if (hit) 63 { 64 for (;;) 65 { 66 iterator_t save = scan.first; 67 if (result_t next = this->subject().parse(scan)) 68 { 69 scan.concat_match(hit, next); 70 } 71 else 72 { 73 scan.first = save; 74 break; 75 } 76 } 77 } 78 return hit; 79 } 80 }; 81 82 #if BOOST_WORKAROUND(BOOST_MSVC, >= 1400) 83 #pragma warning(pop) 84 #endif 85 86 struct positive_parser_gen 87 { 88 template <typename S> 89 struct result 90 { 91 typedef positive<S> type; 92 }; 93 94 template <typename S> 95 static positive<S> generateboost::spirit::positive_parser_gen96 generate(parser<S> const& a) 97 { 98 return positive<S>(a.derived()); 99 } 100 }; 101 102 template <typename S> 103 inline positive<S> 104 operator+(parser<S> const& a); 105 106 BOOST_SPIRIT_CLASSIC_NAMESPACE_END 107 108 }} // namespace BOOST_SPIRIT_CLASSIC_NS 109 110 #endif 111 112 #include <boost/spirit/home/classic/core/composite/impl/positive.ipp> 113