ceph/src/boost/libs/xpressive/include/boost/xpressive/detail/static/transforms/as_modifier.hpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // as_modifier.hpp
   3 //
   4 //  Copyright 2008 Eric Niebler. Distributed under the Boost
   5 //  Software License, Version 1.0. (See accompanying file
   6 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   7
   8 #ifndef BOOST_XPRESSIVE_DETAIL_STATIC_TRANSFORMS_AS_MODIFIER_HPP_EAN_04_05_2007
   9 #define BOOST_XPRESSIVE_DETAIL_STATIC_TRANSFORMS_AS_MODIFIER_HPP_EAN_04_05_2007
  10
  11 // MS compatible compilers support #pragma once
  12 #if defined(_MSC_VER)
  13 # pragma once
  14 #endif
  15
  16 #include <boost/mpl/sizeof.hpp>
  17 #include <boost/xpressive/detail/detail_fwd.hpp>
  18 #include <boost/xpressive/detail/static/static.hpp>
  19 #include <boost/proto/core.hpp>
  20
  21 #define UNCV(x) typename remove_const<x>::type
  22 #define UNREF(x) typename remove_reference<x>::type
  23 #define UNCVREF(x) UNCV(UNREF(x))
  24
  25 namespace boost { namespace xpressive { namespace detail
  26 {
  27     ///////////////////////////////////////////////////////////////////////////////
  28     // regex operator tags
  29     struct modifier_tag
  30     {};
  31
  32 }}}
  33
  34 namespace boost { namespace xpressive { namespace grammar_detail
  35 {
  36
  37     ///////////////////////////////////////////////////////////////////////////////
  38     // as_modifier
  39     template<typename Grammar, typename Callable = proto::callable>
  40     struct as_modifier : proto::transform<as_modifier<Grammar, Callable> >
  41     {
  42         template<typename Expr, typename State, typename Data>
  43         struct impl : proto::transform_impl<Expr, State, Data>
  44         {
  45             typedef
  46                 typename proto::result_of::value<
  47                     typename proto::result_of::left<typename impl::expr>::type
  48                 >::type
  49             modifier_type;
  50
  51             typedef
  52                 typename modifier_type::template apply<typename impl::data>::type
  53             visitor_type;
  54
  55             typedef
  56                 typename proto::result_of::right<Expr>::type
  57             expr_type;
  58
  59             typedef
  60                 typename Grammar::template impl<expr_type, State, visitor_type &>::result_type
  61             result_type;
  62
  63             result_type operator ()(
  64                 typename impl::expr_param expr
  65               , typename impl::state_param state
  66               , typename impl::data_param data
  67             ) const
  68             {
  69                 visitor_type new_visitor(proto::value(proto::left(expr)).call(data));
  70                 return typename Grammar::template impl<expr_type, State, visitor_type &>()(
  71                     proto::right(expr)
  72                   , state
  73                   , new_visitor
  74                 );
  75             }
  76         };
  77     };
  78
  79 }}}
  80
  81 #undef UNCV
  82 #undef UNREF
  83 #undef UNCVREF
  84
  85 #endif