qi/directive/distinct.hpp

0001 //  Copyright (c) 2001-2011 Hartmut Kaiser
0002 //  Copyright (c) 2001-2011 Joel de Guzman
0003 //  Copyright (c) 2003 Vaclav Vesely
0004 //
0005 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
0006 //  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0007
0008 #ifndef BOOST_SPIRIT_REPOSITORY_QI_DIRECTIVE_DISTINCT_HPP
0009 #define BOOST_SPIRIT_REPOSITORY_QI_DIRECTIVE_DISTINCT_HPP
0010
0011 #if defined(_MSC_VER)
0012 #pragma once
0013 #endif
0014
0015 #include <boost/spirit/home/qi/skip_over.hpp>
0016 #include <boost/spirit/home/qi/domain.hpp>
0017 #include <boost/spirit/home/qi/parser.hpp>
0018 #include <boost/spirit/home/qi/meta_compiler.hpp>
0019 #include <boost/spirit/home/qi/detail/unused_skipper.hpp>
0020 #include <boost/spirit/home/support/common_terminals.hpp>
0021 #include <boost/spirit/home/support/make_component.hpp>
0022 #include <boost/spirit/home/support/info.hpp>
0023 #include <boost/spirit/home/support/unused.hpp>
0024 #include <boost/spirit/home/qi/detail/attributes.hpp>
0025 #include <boost/spirit/home/support/string_traits.hpp>
0026 #include <boost/spirit/home/qi/auxiliary/eps.hpp>
0027 #include <boost/spirit/home/qi/auxiliary/lazy.hpp>
0028 #include <boost/spirit/home/qi/directive/lexeme.hpp>
0029 #include <boost/spirit/home/qi/operator/not_predicate.hpp>
0030
0031 #include <boost/spirit/repository/home/support/distinct.hpp>
0032
0033 #include <boost/fusion/include/at.hpp>
0034 #include <boost/fusion/include/vector.hpp>
0035
0036 ///////////////////////////////////////////////////////////////////////////////
0037 namespace boost { namespace spirit
0038 {
0039     ///////////////////////////////////////////////////////////////////////////
0040     // Enablers
0041     ///////////////////////////////////////////////////////////////////////////
0042
0043     // enables distinct(...)[...]
0044     template <typename Tail>
0045     struct use_directive<qi::domain
0046           , terminal_ex<repository::tag::distinct, fusion::vector1<Tail> > >
0047       : mpl::true_ {};
0048
0049     // enables *lazy* distinct(...)[...]
0050     template <>
0051     struct use_lazy_directive<qi::domain, repository::tag::distinct, 1>
0052       : mpl::true_ {};
0053
0054 }}
0055
0056 ///////////////////////////////////////////////////////////////////////////////
0057 namespace boost { namespace spirit { namespace repository {namespace qi
0058 {
0059 #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
0060     using repository::distinct;
0061 #endif
0062     using repository::distinct_type;
0063
0064     template <typename Subject, typename Tail, typename Modifier>
0065     struct distinct_parser
0066       : spirit::qi::unary_parser<distinct_parser<Subject, Tail, Modifier> >
0067     {
0068         template <typename Context, typename Iterator>
0069         struct attribute
0070           : traits::attribute_of<Subject, Context, Iterator>
0071         {};
0072
0073         distinct_parser(Subject const& subject, Tail const& tail)
0074           : subject(subject), tail(tail) {}
0075
0076         template <typename Iterator, typename Context
0077           , typename Skipper, typename Attribute>
0078         bool parse(Iterator& first, Iterator const& last
0079           , Context& context, Skipper const& skipper, Attribute& attr) const
0080         {
0081             Iterator iter = first;
0082
0083             spirit::qi::skip_over(iter, last, skipper);
0084             if (!subject.parse(iter, last, context
0085               , spirit::qi::detail::unused_skipper<Skipper>(skipper), attr))
0086                 return false;
0087
0088             Iterator i = iter;
0089             if (tail.parse(i, last, context, unused, unused))
0090                 return false;
0091
0092             first = iter;
0093             return true;
0094         }
0095
0096         template <typename Context>
0097         info what(Context& ctx) const
0098         {
0099             return info("distinct", subject.what(ctx));
0100         }
0101
0102         Subject subject;
0103         Tail tail;
0104     };
0105
0106 }}}}
0107
0108 ///////////////////////////////////////////////////////////////////////////////
0109 namespace boost { namespace spirit { namespace qi
0110 {
0111     ///////////////////////////////////////////////////////////////////////////
0112     // Parser generators: make_xxx function (objects)
0113     ///////////////////////////////////////////////////////////////////////////
0114     template <typename Tail, typename Subject, typename Modifiers>
0115     struct make_directive<
0116         terminal_ex<repository::tag::distinct, fusion::vector1<Tail> >
0117       , Subject, Modifiers>
0118     {
0119         typedef typename result_of::compile<qi::domain, Tail, Modifiers>::type
0120             tail_type;
0121
0122         typedef repository::qi::distinct_parser<
0123             Subject, tail_type, Modifiers> result_type;
0124
0125         template <typename Terminal>
0126         result_type operator()(Terminal const& term, Subject const& subject
0127           , Modifiers const& modifiers) const
0128         {
0129             return result_type(subject
0130               , compile<qi::domain>(fusion::at_c<0>(term.args), modifiers));
0131         }
0132     };
0133
0134 }}}
0135
0136 namespace boost { namespace spirit { namespace traits
0137 {
0138     template <typename Subject, typename Tail, typename Modifier>
0139     struct has_semantic_action<
0140             repository::qi::distinct_parser<Subject, Tail, Modifier> >
0141       : unary_has_semantic_action<Subject> {};
0142 }}}
0143
0144 #endif
0145