ceph/src/boost/libs/proto/include/boost/proto/transform/integral_c.hpp

   1 ///////////////////////////////////////////////////////////////////////////////
   2 /// \file integral_c.hpp
   3 /// Contains definition of the integral_c transform and friends.
   4 //
   5 //  Copyright 2011 Eric Niebler. Distributed under the Boost
   6 //  Software License, Version 1.0. (See accompanying file
   7 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   8
   9 #ifndef BOOST_PROTO_TRANSFORM_INTEGRAL_C_HPP_EAN_04_28_2011
  10 #define BOOST_PROTO_TRANSFORM_INTEGRAL_C_HPP_EAN_04_28_2011
  11
  12 #include <boost/proto/proto_fwd.hpp>
  13 #include <boost/proto/transform/impl.hpp>
  14
  15 namespace boost { namespace proto
  16 {
  17
  18     /// \brief A PrimitiveTransform that returns a specified
  19     /// integral constant
  20     ///
  21     template<typename T, T I>
  22     struct integral_c : transform<integral_c<T, I> >
  23     {
  24         template<typename Expr, typename State, typename Data>
  25         struct impl : transform_impl<Expr, State, Data>
  26         {
  27             typedef T result_type;
  28
  29             /// \return \c I
  30             /// \throw nothrow
  31             T operator()(
  32                 typename impl::expr_param
  33               , typename impl::state_param
  34               , typename impl::data_param
  35             ) const
  36             {
  37                 return I;
  38             }
  39         };
  40     };
  41
  42     /// \brief A PrimitiveTransform that returns a specified
  43     /// char
  44     ///
  45     template<char I>
  46     struct char_
  47       : integral_c<char, I>
  48     {};
  49
  50     /// \brief A PrimitiveTransform that returns a specified
  51     /// int
  52     ///
  53     template<int I>
  54     struct int_
  55       : integral_c<int, I>
  56     {};
  57
  58     /// \brief A PrimitiveTransform that returns a specified
  59     /// long
  60     ///
  61     template<long I>
  62     struct long_
  63       : integral_c<long, I>
  64     {};
  65
  66     /// \brief A PrimitiveTransform that returns a specified
  67     /// std::size_t
  68     ///
  69     template<std::size_t I>
  70     struct size_t
  71       : integral_c<std::size_t, I>
  72     {};
  73
  74     /// INTERNAL ONLY
  75     ///
  76     template<typename T, T I>
  77     struct is_callable<integral_c<T, I> >
  78       : mpl::true_
  79     {};
  80
  81     /// INTERNAL ONLY
  82     ///
  83     template<char I>
  84     struct is_callable<char_<I> >
  85       : mpl::true_
  86     {};
  87
  88     /// INTERNAL ONLY
  89     ///
  90     template<int I>
  91     struct is_callable<int_<I> >
  92       : mpl::true_
  93     {};
  94
  95     /// INTERNAL ONLY
  96     ///
  97     template<long I>
  98     struct is_callable<long_<I> >
  99       : mpl::true_
 100     {};
 101
 102     /// INTERNAL ONLY
 103     ///
 104     template<std::size_t I>
 105     struct is_callable<size_t<I> >
 106       : mpl::true_
 107     {};
 108
 109 }}
 110
 111 #endif