ceph/src/boost/libs/spirit/include/boost/spirit/home/qi/directive/as.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3     Copyright (c) 2001-2011 Hartmut Kaiser
   4     Copyright (c)      2010 Bryce Lelbach
   5
   6     Distributed under the Boost Software License, Version 1.0. (See accompanying
   7     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   8 =============================================================================*/
   9 #if !defined(SPIRIT_AS_DECEMBER_6_2010_1013AM)
  10 #define SPIRIT_AS_DECEMBER_6_2010_1013AM
  11
  12 #if defined(_MSC_VER)
  13 #pragma once
  14 #endif
  15
  16 #include <boost/spirit/home/qi/meta_compiler.hpp>
  17 #include <boost/spirit/home/qi/skip_over.hpp>
  18 #include <boost/spirit/home/qi/parser.hpp>
  19 #include <boost/spirit/home/qi/detail/assign_to.hpp>
  20 #include <boost/spirit/home/support/unused.hpp>
  21 #include <boost/spirit/home/support/info.hpp>
  22 #include <boost/spirit/home/support/common_terminals.hpp>
  23 #include <boost/spirit/home/support/unused.hpp>
  24 #include <boost/spirit/home/support/has_semantic_action.hpp>
  25 #include <boost/spirit/home/support/handles_container.hpp>
  26 #include <boost/spirit/home/support/assert_msg.hpp>
  27 #include <boost/spirit/home/support/container.hpp>
  28 #include <boost/range/iterator_range.hpp>
  29 #include <string>
  30
  31 namespace boost { namespace spirit { namespace qi
  32 {
  33     template <typename T>
  34     struct as
  35       : stateful_tag_type<T, tag::as>
  36     {
  37         //~ BOOST_SPIRIT_ASSERT_MSG(
  38             //~ (traits::is_container<T>::type::value),
  39             //~ error_type_must_be_a_container,
  40             //~ (T));
  41     };
  42 }}}
  43
  44 namespace boost { namespace spirit
  45 {
  46     ///////////////////////////////////////////////////////////////////////////
  47     // Enablers
  48     ///////////////////////////////////////////////////////////////////////////
  49     // enables as_string[...]
  50     template <>
  51     struct use_directive<qi::domain, tag::as_string>
  52       : mpl::true_ {};
  53
  54     // enables as_wstring[...]
  55     template <>
  56     struct use_directive<qi::domain, tag::as_wstring>
  57       : mpl::true_ {};
  58
  59     // enables as<T>[...]
  60     template <typename T>
  61     struct use_directive<qi::domain, tag::stateful_tag<T, tag::as> >
  62       : mpl::true_
  63     {};
  64 }}
  65
  66 namespace boost { namespace spirit { namespace qi
  67 {
  68 #ifndef BOOST_SPIRIT_NO_PREDEFINED_TERMINALS
  69     using spirit::as_string;
  70     using spirit::as_wstring;
  71 #endif
  72     using spirit::as_string_type;
  73     using spirit::as_wstring_type;
  74
  75     template <typename Subject, typename T>
  76     struct as_directive : unary_parser<as_directive<Subject, T> >
  77     {
  78         typedef Subject subject_type;
  79         as_directive(Subject const& subject_)
  80           : subject(subject_) {}
  81
  82         template <typename Context, typename Iterator>
  83         struct attribute
  84         {
  85             typedef T type;
  86         };
  87
  88         template <typename Iterator, typename Context
  89           , typename Skipper, typename Attribute>
  90         bool parse(Iterator& first, Iterator const& last
  91           , Context& context, Skipper const& skipper, Attribute& attr_) const
  92         {
  93             Iterator i = first;
  94             T as_attr;
  95             if (subject.parse(i, last, context, skipper, as_attr))
  96             {
  97                 spirit::traits::assign_to(as_attr, attr_);
  98                 first = i;
  99                 return true;
 100             }
 101             return false;
 102         }
 103
 104         template <typename Iterator, typename Context, typename Skipper>
 105         bool parse(Iterator& first, Iterator const& last
 106           , Context& context, Skipper const& skipper, T& attr_) const
 107         {
 108             Iterator i = first;
 109             if (subject.parse(i, last, context, skipper, attr_))
 110             {
 111                 first = i;
 112                 return true;
 113             }
 114             return false;
 115         }
 116
 117         template <typename Context>
 118         info what(Context& context) const
 119         {
 120             return info("as", subject.what(context));
 121         }
 122
 123         Subject subject;
 124     };
 125
 126     ///////////////////////////////////////////////////////////////////////////
 127     // Parser generators: make_xxx function (objects)
 128     ///////////////////////////////////////////////////////////////////////////
 129     template <typename Subject, typename Modifiers>
 130     struct make_directive<tag::as_string, Subject, Modifiers>
 131     {
 132         typedef as_directive<Subject, std::string> result_type;
 133         result_type operator()(unused_type, Subject const& subject
 134           , unused_type) const
 135         {
 136             return result_type(subject);
 137         }
 138     };
 139
 140     template <typename Subject, typename Modifiers>
 141     struct make_directive<tag::as_wstring, Subject, Modifiers>
 142     {
 143         typedef as_directive<Subject, std::basic_string<wchar_t> > result_type;
 144         result_type operator()(unused_type, Subject const& subject
 145           , unused_type) const
 146         {
 147             return result_type(subject);
 148         }
 149     };
 150
 151     template <typename T, typename Subject, typename Modifiers>
 152     struct make_directive<tag::stateful_tag<T, tag::as>, Subject, Modifiers>
 153     {
 154         typedef as_directive<Subject, T> result_type;
 155         result_type operator()(unused_type, Subject const& subject
 156           , unused_type) const
 157         {
 158             return result_type(subject);
 159         }
 160     };
 161 }}}
 162
 163 namespace boost { namespace spirit { namespace traits
 164 {
 165     ///////////////////////////////////////////////////////////////////////////
 166     template <typename Subject, typename T>
 167     struct has_semantic_action<qi::as_directive<Subject, T> >
 168       : unary_has_semantic_action<Subject> {};
 169
 170     ///////////////////////////////////////////////////////////////////////////
 171     template <typename Subject, typename T, typename Attribute
 172         , typename Context, typename Iterator>
 173     struct handles_container<qi::as_directive<Subject, T>, Attribute
 174         , Context, Iterator>
 175       : mpl::false_ {};
 176 }}}
 177
 178 #endif