ceph/src/boost/boost/function_types/detail/to_sequence.hpp

   1
   2 // (C) Copyright Tobias Schwinger
   3 //
   4 // Use modification and distribution are subject to the boost Software License,
   5 // Version 1.0. (See http://www.boost.org/LICENSE_1_0.txt).
   6
   7 //------------------------------------------------------------------------------
   8
   9 #ifndef BOOST_FT_DETAIL_TO_SEQUENCE_HPP_INCLUDED
  10 #define BOOST_FT_DETAIL_TO_SEQUENCE_HPP_INCLUDED
  11
  12 #include <boost/mpl/eval_if.hpp>
  13 #include <boost/mpl/identity.hpp>
  14 #include <boost/mpl/is_sequence.hpp>
  15 #include <boost/mpl/placeholders.hpp>
  16 #include <boost/type_traits/add_reference.hpp>
  17
  18 #include <boost/function_types/is_callable_builtin.hpp>
  19
  20 namespace boost { namespace function_types { namespace detail {
  21
  22 // wrap first arguments in components, if callable builtin type
  23 template<typename T>
  24 struct to_sequence
  25 {
  26   typedef typename
  27    mpl::eval_if
  28    < is_callable_builtin<T>
  29    , to_sequence< components<T> >
  30    , mpl::identity< T >
  31    >::type
  32   type;
  33 };
  34
  35 // reduce template instantiations, if possible
  36 template<typename T, typename U>
  37 struct to_sequence< components<T,U> >
  38 {
  39   typedef typename components<T,U>::types type;
  40 };
  41
  42 } } } // namespace ::boost::function_types::detail
  43
  44 #endif
  45