initial checkin

[SVN r12861]

include/boost/python/lvalue_from_python.hpp

@@ -0,0 +1,96 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef LVALUE_FROM_PYTHON_DWA2002130_HPP
+# define LVALUE_FROM_PYTHON_DWA2002130_HPP
+
+# include <boost/python/converter/from_python.hpp>
+# include <boost/python/type_from_python.hpp>
+
+namespace boost { namespace python { 
+
+// Utility which produces a member extractor function on platforms
+// other than VC6.
+template <class Class, class Member, Member (Class::*mp)>
+struct get_member
+{
+    static Member& execute(Class& c)
+    {
+        return c.*mp;
+    }
+};
+
+namespace detail
+{
+  template <class Class>
+  struct extract_identity
+  {
+      static Class& execute(Class& c)
+      {
+          return c;
+      }
+  };
+}
+
+template <
+    PyTypeObject const* python_type
+    , class Value
+    , class PythonObject = Value
+    , class Extract = detail::extract_identity<Value>
+    >
+class lvalue_from_python
+{
+    typedef type_from_python<python_type> convertible_t;
+ public:
+    
+    lvalue_from_python()
+        : m_mutable_converter(
+            &convertible_t::convertible, convert_mutable)
+        
+        , m_const_converter(
+            &convertible_t::convertible, convert_const)
+
+        , m_mutable_pointer_converter(
+            &convertible_t::convertible, convert_mutable_pointer)
+        
+        , m_const_pointer_converter(
+            &convertible_t::convertible, convert_const_pointer)
+    {}
+    
+ private:
+    static Value& convert_mutable(PyObject* op, converter::from_python_data&)
+    {
+        return Extract::execute(*(PythonObject*)op);
+    }
+    
+    static Value const& convert_const(PyObject* op, converter::from_python_data&)
+    {
+        return Extract::execute(*(PythonObject*)op);
+    }
+    
+    static Value* convert_mutable_pointer(PyObject* op, converter::from_python_data&)
+    {
+        return &Extract::execute(*(PythonObject*)op);
+    }
+    
+    static Value const* convert_const_pointer(PyObject* op, converter::from_python_data&)
+    {
+        return &Extract::execute(*(PythonObject*)op);
+    }
+    
+    typedef converter::from_python_converter<Value&> mutable_converter;
+    typedef converter::from_python_converter<Value const&> const_converter;
+    typedef converter::from_python_converter<Value*> mutable_pointer_converter;
+    typedef converter::from_python_converter<Value const*> const_pointer_converter;
+    
+    mutable_converter m_mutable_converter;
+    const_converter m_const_converter;
+    mutable_pointer_converter m_mutable_pointer_converter;
+    const_pointer_converter m_const_pointer_converter;
+};
+
+}} // namespace boost::python
+
+#endif // LVALUE_FROM_PYTHON_DWA2002130_HPP