luabind/container_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_CONTAINER_POLICY_HPP_INCLUDED
  25 #define LUABIND_CONTAINER_POLICY_HPP_INCLUDED
  26
  27 #include <luabind/config.hpp>
  28 #include <luabind/detail/policy.hpp>
  29 #include <boost/mpl/apply_wrap.hpp>
  30
  31 namespace luabind { namespace detail {
  32
  33         namespace mpl = boost::mpl;
  34
  35         template<class Policies>
  36         struct container_converter_lua_to_cpp
  37         {
  38         int const consumed_args(...)
  39         {
  40             return 1;
  41         }
  42
  43         template<class T>
  44                 T apply(lua_State* L, by_const_reference<T>, int index)
  45                 {
  46                         typedef typename T::value_type value_type;
  47
  48                         typedef typename find_conversion_policy<1, Policies>::type converter_policy;
  49                         typename mpl::apply_wrap2<converter_policy,value_type,lua_to_cpp>::type converter;
  50
  51                         T container;
  52
  53                         lua_pushnil(L);
  54                         while (lua_next(L, index))
  55                         {
  56                                 container.push_back(converter.apply(L, LUABIND_DECORATE_TYPE(value_type), -1));
  57                                 lua_pop(L, 1); // pop value
  58                         }
  59
  60                         return container;
  61                 }
  62
  63                 template<class T>
  64                 T apply(lua_State* L, by_value<T>, int index)
  65                 {
  66                         return apply(L, by_const_reference<T>(), index);
  67                 }
  68
  69                 template<class T>
  70                 static int match(lua_State* L, by_const_reference<T>, int index)
  71                 {
  72                         if (lua_istable(L, index)) return 0; else return -1;
  73                 }
  74
  75                 template<class T>
  76                 void converter_postcall(lua_State*, T, int) {}
  77         };
  78
  79         template<class Policies>
  80         struct container_converter_cpp_to_lua
  81         {
  82                 template<class T>
  83                 void apply(lua_State* L, const T& container)
  84                 {
  85                         typedef typename T::value_type value_type;
  86
  87                         typedef typename find_conversion_policy<1, Policies>::type converter_policy;
  88                         typename mpl::apply_wrap2<converter_policy,value_type,lua_to_cpp>::type converter;
  89
  90                         lua_newtable(L);
  91
  92                         int index = 1;
  93
  94                         for (typename T::const_iterator i = container.begin(); i != container.end(); ++i)
  95                         {
  96                                 converter.apply(L, *i);
  97                                 lua_rawseti(L, -2, index);
  98                                 ++index;
  99                         }
 100                 }
 101         };
 102
 103         template<int N, class Policies>
 104 //      struct container_policy : converter_policy_tag
 105         struct container_policy : conversion_policy<N>
 106         {
 107 //              BOOST_STATIC_CONSTANT(int, index = N);
 108
 109                 static void precall(lua_State*, const index_map&) {}
 110                 static void postcall(lua_State*, const index_map&) {}
 111
 112                 struct only_accepts_nonconst_pointers {};
 113
 114                 template<class T, class Direction>
 115                 struct apply
 116                 {
 117                         typedef typename boost::mpl::if_<boost::is_same<lua_to_cpp, Direction>
 118                                 , container_converter_lua_to_cpp<Policies>
 119                                 , container_converter_cpp_to_lua<Policies>
 120                         >::type type;
 121                 };
 122         };
 123
 124 }}
 125
 126 namespace luabind
 127 {
 128         template<int N>
 129         detail::policy_cons<detail::container_policy<N, detail::null_type>, detail::null_type>
 130         container(LUABIND_PLACEHOLDER_ARG(N))
 131         {
 132                 return detail::policy_cons<detail::container_policy<N, detail::null_type>, detail::null_type>();
 133         }
 134
 135         template<int N, class Policies>
 136         detail::policy_cons<detail::container_policy<N, Policies>, detail::null_type>
 137         container(LUABIND_PLACEHOLDER_ARG(N), const Policies&)
 138         {
 139                 return detail::policy_cons<detail::container_policy<N, Policies>, detail::null_type>();
 140         }
 141 }
 142
 143 #endif // LUABIND_CONTAINER_POLICY_HPP_INCLUDED