git.sesse.net Git - casparcg/blob - dependencies/boost/boost/python/object/value_holder.hpp

   1 #if !defined(BOOST_PP_IS_ITERATING)
   2
   3 // Copyright David Abrahams 2001.
   4 // Distributed under the Boost Software License, Version 1.0. (See
   5 // accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt)
   7
   8 # ifndef VALUE_HOLDER_DWA20011215_HPP
   9 #  define VALUE_HOLDER_DWA20011215_HPP
  10
  11 #  include <boost/python/object/value_holder_fwd.hpp>
  12
  13 #  include <boost/python/instance_holder.hpp>
  14 #  include <boost/python/type_id.hpp>
  15 #  include <boost/python/wrapper.hpp>
  16
  17 #  include <boost/python/object/inheritance_query.hpp>
  18 #  include <boost/python/object/forward.hpp>
  19
  20 #  include <boost/python/detail/force_instantiate.hpp>
  21 #  include <boost/python/detail/preprocessor.hpp>
  22
  23 #  include <boost/preprocessor/comma_if.hpp>
  24 #  include <boost/preprocessor/enum_params.hpp>
  25 #  include <boost/preprocessor/iterate.hpp>
  26 #  include <boost/preprocessor/repeat.hpp>
  27 #  include <boost/preprocessor/debug/line.hpp>
  28
  29 #  include <boost/preprocessor/repetition/enum_params.hpp>
  30 #  include <boost/preprocessor/repetition/enum_binary_params.hpp>
  31
  32 #  include <boost/utility/addressof.hpp>
  33
  34 namespace boost { namespace python { namespace objects {
  35
  36 #  if BOOST_WORKAROUND(__GNUC__, == 2)
  37 #   define BOOST_PYTHON_UNFORWARD_LOCAL(z, n, _) BOOST_PP_COMMA_IF(n) (typename unforward<A##n>::type)objects::do_unforward(a##n,0)
  38 #  else
  39 #   define BOOST_PYTHON_UNFORWARD_LOCAL(z, n, _) BOOST_PP_COMMA_IF(n) objects::do_unforward(a##n,0)
  40 #  endif
  41
  42 template <class Value>
  43 struct value_holder : instance_holder
  44 {
  45     typedef Value held_type;
  46     typedef Value value_type;
  47
  48     // Forward construction to the held object
  49 #  define BOOST_PP_ITERATION_PARAMS_1 (4, (0, BOOST_PYTHON_MAX_ARITY, <boost/python/object/value_holder.hpp>, 1))
  50 #  include BOOST_PP_ITERATE()
  51
  52  private: // required holder implementation
  53     void* holds(type_info, bool null_ptr_only);
  54
  55     template <class T>
  56     inline void* holds_wrapped(type_info dst_t, wrapper<T>*,T* p)
  57     {
  58         return python::type_id<T>() == dst_t ? p : 0;
  59     }
  60
  61     inline void* holds_wrapped(type_info, ...)
  62     {
  63         return 0;
  64     }
  65  private: // data members
  66     Value m_held;
  67 };
  68
  69 template <class Value, class Held>
  70 struct value_holder_back_reference : instance_holder
  71 {
  72     typedef Held held_type;
  73     typedef Value value_type;
  74
  75     // Forward construction to the held object
  76 #  define BOOST_PP_ITERATION_PARAMS_1 (4, (0, BOOST_PYTHON_MAX_ARITY, <boost/python/object/value_holder.hpp>, 2))
  77 #  include BOOST_PP_ITERATE()
  78
  79 private: // required holder implementation
  80     void* holds(type_info, bool null_ptr_only);
  81
  82  private: // data members
  83     Held m_held;
  84 };
  85
  86 #  undef BOOST_PYTHON_UNFORWARD_LOCAL
  87
  88 template <class Value>
  89 void* value_holder<Value>::holds(type_info dst_t, bool /*null_ptr_only*/)
  90 {
  91     if (void* wrapped = holds_wrapped(dst_t, boost::addressof(m_held), boost::addressof(m_held)))
  92         return wrapped;
  93
  94     type_info src_t = python::type_id<Value>();
  95     return src_t == dst_t ? boost::addressof(m_held)
  96         : find_static_type(boost::addressof(m_held), src_t, dst_t);
  97 }
  98
  99 template <class Value, class Held>
 100 void* value_holder_back_reference<Value,Held>::holds(
 101     type_info dst_t, bool /*null_ptr_only*/)
 102 {
 103     type_info src_t = python::type_id<Value>();
 104     Value* x = &m_held;
 105
 106     if (dst_t == src_t)
 107         return x;
 108     else if (dst_t == python::type_id<Held>())
 109         return &m_held;
 110     else
 111         return find_static_type(x, src_t, dst_t);
 112 }
 113
 114 }}} // namespace boost::python::objects
 115
 116 # endif // VALUE_HOLDER_DWA20011215_HPP
 117
 118 // --------------- value_holder ---------------
 119
 120 // For gcc 4.4 compatability, we must include the
 121 // BOOST_PP_ITERATION_DEPTH test inside an #else clause.
 122 #else // BOOST_PP_IS_ITERATING
 123 #if BOOST_PP_ITERATION_DEPTH() == 1 && BOOST_PP_ITERATION_FLAGS() == 1
 124 # if !(BOOST_WORKAROUND(__MWERKS__, > 0x3100)                      \
 125         && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3201)))
 126 #  line BOOST_PP_LINE(__LINE__, value_holder.hpp(value_holder))
 127 # endif
 128
 129 # define N BOOST_PP_ITERATION()
 130
 131 # if (N != 0)
 132     template <BOOST_PP_ENUM_PARAMS_Z(1, N, class A)>
 133 # endif
 134     value_holder(
 135       PyObject* self BOOST_PP_COMMA_IF(N) BOOST_PP_ENUM_BINARY_PARAMS_Z(1, N, A, a))
 136         : m_held(
 137             BOOST_PP_REPEAT_1ST(N, BOOST_PYTHON_UNFORWARD_LOCAL, nil)
 138             )
 139     {
 140         python::detail::initialize_wrapper(self, boost::addressof(this->m_held));
 141     }
 142
 143 # undef N
 144
 145 // --------------- value_holder_back_reference ---------------
 146
 147 #elif BOOST_PP_ITERATION_DEPTH() == 1 && BOOST_PP_ITERATION_FLAGS() == 2
 148 # if !(BOOST_WORKAROUND(__MWERKS__, > 0x3100)                      \
 149         && BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3201)))
 150 #  line BOOST_PP_LINE(__LINE__, value_holder.hpp(value_holder_back_reference))
 151 # endif
 152
 153 # define N BOOST_PP_ITERATION()
 154
 155 # if (N != 0)
 156     template <BOOST_PP_ENUM_PARAMS_Z(1, N, class A)>
 157 # endif
 158     value_holder_back_reference(
 159         PyObject* p BOOST_PP_COMMA_IF(N) BOOST_PP_ENUM_BINARY_PARAMS_Z(1, N, A, a))
 160         : m_held(
 161             p BOOST_PP_COMMA_IF(N)
 162             BOOST_PP_REPEAT_1ST(N, BOOST_PYTHON_UNFORWARD_LOCAL, nil)
 163             )
 164     {
 165     }
 166
 167 # undef N
 168
 169 #endif // BOOST_PP_ITERATION_DEPTH()
 170 #endif