ceph/src/boost/boost/parameter/aux_/preprocessor/impl/parenthesized_type.hpp

   1 // Copyright David Abrahams 2006.
   2 // Distributed under the Boost Software License, Version 1.0.
   3 // (See accompanying file LICENSE_1_0.txt or copy at
   4 // http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef BOOST_PARAMETER_AUX_PREPROCESSOR_IMPL_PARENTHESIZED_TYPE_HPP
   7 #define BOOST_PARAMETER_AUX_PREPROCESSOR_IMPL_PARENTHESIZED_TYPE_HPP
   8
   9 namespace boost { namespace parameter { namespace aux {
  10
  11     // A metafunction that transforms void(*)(T) -> T
  12     template <typename UnaryFunctionPointer>
  13     struct unaryfunptr_arg_type;
  14
  15     template <typename Arg>
  16     struct unaryfunptr_arg_type<void(*)(Arg)>
  17     {
  18         typedef Arg type;
  19     };
  20
  21     template <>
  22     struct unaryfunptr_arg_type<void(*)(void)>
  23     {
  24         typedef void type;
  25     };
  26 }}} // namespace boost::parameter::aux
  27
  28 // A macro that takes a parenthesized C++ type name (T) and transforms it
  29 // into an un-parenthesized type expression equivalent to T.
  30 #define BOOST_PARAMETER_PARENTHESIZED_TYPE(x)                                \
  31     ::boost::parameter::aux::unaryfunptr_arg_type< void(*)x >::type
  32
  33 #endif  // include guard
  34