ceph/src/boost/libs/metaparse/example/meta_hs/semantic.hpp

   1 #ifndef META_HS_SEMANTIC_HPP
   2 #define META_HS_SEMANTIC_HPP
   3
   4 // Copyright Abel Sinkovics (abel@sinkovics.hu)  2012.
   5 // Distributed under the Boost Software License, Version 1.0.
   6 //    (See accompanying file LICENSE_1_0.txt or copy at
   7 //          http://www.boost.org/LICENSE_1_0.txt)
   8
   9 #include <ast.hpp>
  10 #include <curry.hpp>
  11
  12 #include <boost/mpl/if.hpp>
  13 #include <boost/mpl/apply_wrap.hpp>
  14 #include <boost/mpl/front.hpp>
  15 #include <boost/mpl/back.hpp>
  16 #include <boost/mpl/at.hpp>
  17 #include <boost/mpl/pair.hpp>
  18
  19 namespace semantic
  20 {
  21   struct ref
  22   {
  23     typedef ref type;
  24
  25     template <class Name>
  26     struct apply : ast::ref<Name> {};
  27   };
  28
  29   struct value
  30   {
  31     typedef value type;
  32
  33     template <class V>
  34     struct apply : ast::value<V> {};
  35   };
  36
  37   struct lambda
  38   {
  39     typedef lambda type;
  40
  41     template <class F, class ArgName>
  42     struct apply : ast::lambda<F, ArgName> {};
  43   };
  44
  45   struct application
  46   {
  47     typedef application type;
  48
  49     template <class F, class Arg>
  50     struct apply : ast::application<F, Arg> {};
  51   };
  52
  53   class if_
  54   {
  55   private:
  56     template <class C, class T, class F>
  57     struct lazy_if : boost::mpl::if_<typename C::type, T, F> {};
  58   public:
  59     typedef if_ type;
  60
  61     template <class Seq>
  62     struct apply :
  63       boost::mpl::apply_wrap2<
  64         application,
  65         typename boost::mpl::apply_wrap2<
  66           application,
  67           typename boost::mpl::apply_wrap2<
  68             application,
  69             ast::value<curry3<lazy_if> >,
  70             typename boost::mpl::at_c<Seq, 0>::type
  71           >::type,
  72           typename boost::mpl::at_c<Seq, 1>::type
  73         >::type,
  74         typename boost::mpl::at_c<Seq, 2>::type
  75       >
  76     {};
  77   };
  78
  79   struct binary_op
  80   {
  81     typedef binary_op type;
  82
  83     template <class Exp, class C>
  84     struct apply :
  85       boost::mpl::apply_wrap2<
  86         application,
  87         typename boost::mpl::apply_wrap2<
  88           application,
  89           typename boost::mpl::apply_wrap1<
  90             ref,
  91             typename boost::mpl::front<C>::type
  92           >::type,
  93           Exp
  94         >::type,
  95         typename boost::mpl::back<C>::type
  96       >
  97     {};
  98   };
  99
 100   struct pair
 101   {
 102     typedef pair type;
 103
 104     template <class Seq>
 105     struct apply :
 106       boost::mpl::pair<
 107         typename boost::mpl::front<Seq>::type,
 108         ast::top_bound<typename boost::mpl::back<Seq>::type>
 109       >
 110     {};
 111   };
 112 }
 113
 114 #endif
 115