luabind/yield_policy.hpp

   1 // Copyright (c) 2003 Daniel Wallin and Arvid Norberg
   2
   3 // Permission is hereby granted, free of charge, to any person obtaining a
   4 // copy of this software and associated documentation files (the "Software"),
   5 // to deal in the Software without restriction, including without limitation
   6 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
   7 // and/or sell copies of the Software, and to permit persons to whom the
   8 // Software is furnished to do so, subject to the following conditions:
   9
  10 // The above copyright notice and this permission notice shall be included
  11 // in all copies or substantial portions of the Software.
  12
  13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
  14 // ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
  15 // TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
  16 // PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
  17 // SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
  18 // ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  19 // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
  21 // OR OTHER DEALINGS IN THE SOFTWARE.
  22
  23
  24 #ifndef LUABIND_YIELD_POLICY_HPP_INCLUDED
  25 #define LUABIND_YIELD_POLICY_HPP_INCLUDED
  26
  27 #include <luabind/config.hpp>
  28 #include <luabind/detail/policy.hpp>
  29
  30 namespace luabind { namespace detail
  31 {
  32         struct yield_policy
  33         {
  34                 static void precall(lua_State*, const index_map&) {}
  35                 static void postcall(lua_State*, const index_map&) {}
  36         };
  37
  38         template<class T>
  39         struct has_yield
  40         {
  41                 BOOST_STATIC_CONSTANT(bool,
  42                         value = (boost::is_same<yield_policy, typename T::head>::value ||
  43                                           has_yield<typename T::tail>::value));
  44         };
  45
  46         template<>
  47         struct has_yield<null_type>
  48         {
  49                 BOOST_STATIC_CONSTANT(bool, value = false);
  50         };
  51 }}
  52
  53 namespace luabind
  54 {
  55   detail::policy_cons<detail::yield_policy, detail::null_type> const yield = {};
  56
  57   namespace detail
  58   {
  59     inline void ignore_unused_yield()
  60     {
  61         (void)yield;
  62     }
  63   }
  64 }
  65
  66 #endif // LUABIND_YIELD_POLICY_HPP_INCLUDED
  67