| /*============================================================================= |
| Copyright (c) 2001-2010 Joel de Guzman |
| |
| 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_CHAR_PARSER_APR_16_2006_0906AM) |
| #define BOOST_SPIRIT_CHAR_PARSER_APR_16_2006_0906AM |
| |
| #if defined(_MSC_VER) |
| #pragma once |
| #endif |
| |
| #include <boost/spirit/home/qi/domain.hpp> |
| #include <boost/spirit/home/qi/parser.hpp> |
| #include <boost/spirit/home/qi/detail/assign_to.hpp> |
| #include <boost/spirit/home/qi/meta_compiler.hpp> |
| #include <boost/spirit/home/qi/skip_over.hpp> |
| #include <boost/spirit/home/support/unused.hpp> |
| #include <boost/spirit/home/support/info.hpp> |
| |
| namespace boost { namespace spirit |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // Enablers |
| /////////////////////////////////////////////////////////////////////////// |
| template <> |
| struct use_operator<qi::domain, proto::tag::complement> // enables ~ |
| : mpl::true_ {}; |
| }} |
| |
| namespace boost { namespace spirit { namespace traits // classification |
| { |
| namespace detail |
| { |
| BOOST_MPL_HAS_XXX_TRAIT_DEF(char_parser_id) |
| } |
| |
| template <typename T> |
| struct is_char_parser : detail::has_char_parser_id<T> {}; |
| }}} |
| |
| namespace boost { namespace spirit { namespace qi |
| { |
| /////////////////////////////////////////////////////////////////////////// |
| // The base char_parser |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename Derived, typename Char, typename Attr = Char> |
| struct char_parser : primitive_parser<Derived> |
| { |
| typedef Char char_type; |
| struct char_parser_id; |
| |
| // if Attr is unused_type, Derived must supply its own attribute |
| // metafunction |
| template <typename Context, typename Iterator> |
| struct attribute |
| { |
| typedef Attr type; |
| }; |
| |
| template <typename Iterator, typename Context, typename Skipper, typename Attribute> |
| bool parse(Iterator& first, Iterator const& last |
| , Context& context, Skipper const& skipper, Attribute& attr) const |
| { |
| qi::skip_over(first, last, skipper); |
| |
| if (first != last && this->derived().test(*first, context)) |
| { |
| spirit::traits::assign_to(*first, attr); |
| ++first; |
| return true; |
| } |
| return false; |
| } |
| |
| // Requirement: p.test(ch, context) -> bool |
| // |
| // ch: character being parsed |
| // context: enclosing rule context |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // negated_char_parser handles ~cp expressions (cp is a char_parser) |
| /////////////////////////////////////////////////////////////////////////// |
| template <typename Positive> |
| struct negated_char_parser : |
| char_parser<negated_char_parser<Positive>, typename Positive::char_type> |
| { |
| negated_char_parser(Positive const& positive) |
| : positive(positive) {} |
| |
| template <typename CharParam, typename Context> |
| bool test(CharParam ch, Context& context) const |
| { |
| return !positive.test(ch, context); |
| } |
| |
| template <typename Context> |
| info what(Context& context) const |
| { |
| return info("not", positive.what(context)); |
| } |
| |
| Positive positive; |
| }; |
| |
| /////////////////////////////////////////////////////////////////////////// |
| // Parser generators: make_xxx function (objects) |
| /////////////////////////////////////////////////////////////////////////// |
| namespace detail |
| { |
| template <typename Positive> |
| struct make_negated_char_parser |
| { |
| typedef negated_char_parser<Positive> result_type; |
| result_type operator()(Positive const& positive) const |
| { |
| return result_type(positive); |
| } |
| }; |
| |
| template <typename Positive> |
| struct make_negated_char_parser<negated_char_parser<Positive> > |
| { |
| typedef Positive result_type; |
| result_type operator()(negated_char_parser<Positive> const& ncp) const |
| { |
| return ncp.positive; |
| } |
| }; |
| } |
| |
| template <typename Elements, typename Modifiers> |
| struct make_composite<proto::tag::complement, Elements, Modifiers> |
| { |
| typedef typename |
| fusion::result_of::value_at_c<Elements, 0>::type |
| subject; |
| |
| BOOST_SPIRIT_ASSERT_MSG(( |
| traits::is_char_parser<subject>::value |
| ), subject_is_not_negatable, (subject)); |
| |
| typedef typename |
| detail::make_negated_char_parser<subject>::result_type |
| result_type; |
| |
| result_type operator()(Elements const& elements, unused_type) const |
| { |
| return detail::make_negated_char_parser<subject>()( |
| fusion::at_c<0>(elements)); |
| } |
| }; |
| }}} |
| |
| #endif |