ceph/src/boost/libs/parameter/include/boost/parameter/aux_/template_keyword.hpp

   1 // Copyright Daniel Wallin 2006. Use, modification and distribution is
   2 // subject to the Boost Software License, Version 1.0. (See accompanying
   3 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   4
   5 #ifndef BOOST_PARAMETER_TEMPLATE_KEYWORD_060203_HPP
   6 # define BOOST_PARAMETER_TEMPLATE_KEYWORD_060203_HPP
   7
   8 # include <boost/mpl/and.hpp>
   9 # include <boost/mpl/not.hpp>
  10 # include <boost/type_traits/is_convertible.hpp>
  11 # include <boost/type_traits/is_reference.hpp>
  12
  13 namespace boost { namespace parameter {
  14
  15 namespace aux
  16 {
  17
  18   struct template_keyword_tag {};
  19
  20   template <class T, class U>
  21   struct is_pointer_convertible
  22     : is_convertible<T*, U*>
  23   {};
  24
  25   template <class T>
  26   struct is_template_keyword
  27     : mpl::and_<
  28           mpl::not_<is_reference<T> >
  29         , is_pointer_convertible<T, template_keyword_tag>
  30       >
  31   {};
  32
  33 } // namespace aux
  34
  35 template <class Tag, class T>
  36 struct template_keyword
  37   : aux::template_keyword_tag
  38 {
  39     typedef Tag key_type;
  40     typedef T value_type;
  41     typedef value_type reference;
  42 };
  43
  44 }} // namespace boost::parameter
  45
  46 #endif // BOOST_PARAMETER_TEMPLATE_KEYWORD_060203_HPP
  47