ceph/src/boost/libs/spirit/include/boost/spirit/home/support/nonterminal/extract_param.hpp

   1 /*=============================================================================
   2     Copyright (c) 2001-2011 Joel de Guzman
   3     Copyright (c) 2001-2011 Hartmut Kaiser
   4     Copyright (c) 2009 Francois Barel
   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(BOOST_SPIRIT_EXTRACT_PARAM_AUGUST_08_2009_0848AM)
  10 #define BOOST_SPIRIT_EXTRACT_PARAM_AUGUST_08_2009_0848AM
  11
  12 #if defined(_MSC_VER)
  13 #pragma once
  14 #endif
  15
  16 #include <boost/spirit/home/support/meta_compiler.hpp>
  17 #include <boost/spirit/home/support/nonterminal/locals.hpp>
  18 #include <boost/spirit/home/support/unused.hpp>
  19 #include <boost/spirit/home/support/common_terminals.hpp>
  20
  21 #include <boost/function_types/is_function.hpp>
  22 #include <boost/function_types/parameter_types.hpp>
  23 #include <boost/function_types/result_type.hpp>
  24 #include <boost/fusion/include/as_list.hpp>
  25 #include <boost/fusion/include/as_vector.hpp>
  26 #include <boost/mpl/deref.hpp>
  27 #include <boost/mpl/end.hpp>
  28 #include <boost/mpl/eval_if.hpp>
  29 #include <boost/mpl/find_if.hpp>
  30 #include <boost/mpl/identity.hpp>
  31 #include <boost/mpl/if.hpp>
  32 #include <boost/mpl/or.hpp>
  33 #include <boost/mpl/and.hpp>
  34 #include <boost/mpl/placeholders.hpp>
  35 #include <boost/type_traits/is_same.hpp>
  36
  37 namespace boost { namespace spirit { namespace detail
  38 {
  39     ///////////////////////////////////////////////////////////////////////////
  40     // Helpers to extract params (locals, attributes, ...) from nonterminal
  41     // template arguments
  42     ///////////////////////////////////////////////////////////////////////////
  43     template <typename Types, typename Pred, typename Default>
  44     struct extract_param
  45     {
  46         typedef typename mpl::find_if<Types, Pred>::type pos;
  47
  48         typedef typename
  49             mpl::eval_if<
  50                 is_same<pos, typename mpl::end<Types>::type>
  51               , mpl::identity<Default>
  52               , mpl::deref<pos>
  53             >::type
  54         type;
  55     };
  56
  57     ///////////////////////////////////////////////////////////////////////////
  58     template <typename Types>
  59     struct extract_locals
  60       : fusion::result_of::as_vector<
  61             typename extract_param<
  62                 Types
  63               , is_locals<mpl::_>
  64               , locals<>
  65             >::type
  66         >
  67     {};
  68
  69     ///////////////////////////////////////////////////////////////////////////
  70     template <typename Domain, typename Types>
  71     struct extract_component
  72       : spirit::result_of::compile<
  73             Domain
  74           , typename extract_param<
  75                 Types
  76               , traits::matches<Domain, mpl::_>
  77               , unused_type
  78             >::type
  79         >
  80     {};
  81
  82     ///////////////////////////////////////////////////////////////////////////
  83     template <typename T>
  84     struct make_function_type : mpl::identity<T()> {};
  85
  86     ///////////////////////////////////////////////////////////////////////////
  87     template <typename Types, typename Encoding, typename Domain>
  88     struct extract_sig
  89     {
  90         typedef typename
  91             extract_param<
  92                 Types
  93               , mpl::or_<
  94                     function_types::is_function<mpl::_>
  95                   , mpl::and_<
  96                         mpl::not_<is_locals<mpl::_> >
  97                       , mpl::not_<is_same<mpl::_, Encoding> >
  98                       , mpl::not_<traits::matches<Domain, mpl::_> >
  99                       , mpl::not_<is_same<mpl::_, unused_type> >
 100                     >
 101                 >
 102               , void()
 103             >::type
 104         attr_of_ftype;
 105
 106         typedef typename
 107             mpl::eval_if<
 108                 function_types::is_function<attr_of_ftype>
 109               , mpl::identity<attr_of_ftype>
 110               , make_function_type<attr_of_ftype>
 111             >::type
 112         type;
 113     };
 114
 115     template <typename Sig>
 116     struct attr_from_sig
 117     {
 118         typedef typename function_types::result_type<Sig>::type attr;
 119
 120         typedef typename
 121             mpl::if_<
 122                 is_same<attr, void>
 123               , unused_type
 124               , attr
 125             >::type
 126         type;
 127     };
 128
 129     template <typename Sig>
 130     struct params_from_sig
 131     {
 132         typedef typename function_types::parameter_types<Sig>::type params;
 133
 134         typedef typename fusion::result_of::as_list<params>::type type;
 135     };
 136
 137     ///////////////////////////////////////////////////////////////////////////
 138     template <typename Types>
 139     struct extract_encoding
 140       : extract_param<
 141             Types
 142           , is_char_encoding<mpl::_>
 143           , unused_type
 144         >
 145     {};
 146 }}}
 147
 148 #endif