Added a class PEP252Mixin. By adding this to your ObjectDefinition you

get PEP-252 style objects in stead of old-fashioned objects.
In stead of defining a GetattrHook you declare a class variable getsetlist,
which contains tuples (name, getcode, setcode, docstring).
Only lightly tested: the code still works if you don't inherit PEP252Mixin
and the code works if you inherit it but don't define any getters
or setters. Also, this will not work together with the "poor mans inheritance"
offered by method chains, so the CF module will remain with old-style
objects until PEP253 is supported too.

Tools/bgen/bgen/bgenObjectDefinition.py

@@ -23,6 +23,8 @@ class ObjectDefinition(GeneratorGroup):
 		self.argref = ""	# set to "*" if arg to <type>_New should be pointer
 		self.static = "static " # set to "" to make <type>_New and <type>_Convert public
 		self.modulename = None
+		if hasattr(self, "assertions"):
+			self.assertions()
 
 	def add(self, g, dupcheck=0):
 		g.setselftype(self.objecttype, self.itselftype)
@@ -62,8 +64,7 @@ class ObjectDefinition(GeneratorGroup):
 		GeneratorGroup.generate(self)
 
 		Output()
-		Output("%sPyMethodChain %s_chain = { %s_methods, %s };",
+		self.outputMethodChain()
-		        self.static,    self.prefix, self.prefix, self.basechain)
 
 		self.outputGetattr()
 
@@ -79,6 +80,10 @@ class ObjectDefinition(GeneratorGroup):
 
 		OutHeader2("End object type " + self.name)
 		
+	def outputMethodChain(self):
+		Output("%sPyMethodChain %s_chain = { %s_methods, %s };",
+		        self.static,    self.prefix, self.prefix, self.basechain)
+
 	def outputStructMembers(self):
 		Output("%s ob_itself;", self.itselftype)
 
@@ -200,7 +205,127 @@ class ObjectDefinition(GeneratorGroup):
 		                                           self.name)
 		DedentLevel()
 
+class PEP252Mixin:
+	getsetlist = []
 	
+	def assertions(self):
+		# Check that various things aren't overridden. If they are it could
+		# signify a bgen-client that has been partially converted to PEP252.
+		assert self.outputGetattr.im_func == PEP252Mixin.outputGetattr.im_func
+		assert self.outputSetattr.im_func == PEP252Mixin.outputSetattr.im_func
+		assert self.outputGetattrBody == None
+		assert self.outputGetattrHook == None
+		
+	def outputGetattr(self):
+		pass
+		
+	outputGetattrBody = None
+
+	outputGetattrHook = None
+
+	def outputSetattr(self):
+		pass
+	
+	def outputMethodChain(self):
+		# This is a good place to output the getters and setters
+		self.outputGetSetList()
+	
+	def outputHook(self, name):
+		methodname = "outputHook_" + name
+		if hasattr(self, methodname):
+			func = getattr(self, methodname)
+			func()
+		else:
+			Output("0, /*%s*/", methodname)
+	
+	def outputTypeObject(self):
+		sf = self.static and "static "
+		Output()
+		Output("%sPyTypeObject %s = {", sf, self.typename)
+		IndentLevel()
+		Output("PyObject_HEAD_INIT(NULL)")
+		Output("0, /*ob_size*/")
+		if self.modulename:
+			Output("\"%s.%s\", /*tp_name*/", self.modulename, self.name)
+		else:
+			Output("\"%s\", /*tp_name*/", self.name)
+		Output("sizeof(%s), /*tp_basicsize*/", self.objecttype)
+		Output("0, /*tp_itemsize*/")
+		
+		Output("/* methods */")
+		Output("(destructor) %s_dealloc, /*tp_dealloc*/", self.prefix)
+		Output("0, /*tp_print*/")
+		Output("(getattrfunc)0, /*tp_getattr*/")
+		Output("(setattrfunc)0, /*tp_setattr*/")
+		Output("(cmpfunc) %s_compare, /*tp_compare*/", self.prefix)
+		Output("(reprfunc) %s_repr, /*tp_repr*/", self.prefix)
+		
+		Output("(PyNumberMethods *)0, /* tp_as_number */")
+		Output("(PySequenceMethods *)0, /* tp_as_sequence */")
+		Output("(PyMappingMethods *)0, /* tp_as_mapping */")
+		
+		Output("(hashfunc) %s_hash, /*tp_hash*/", self.prefix)
+		Output("0, /*tp_call*/")
+		Output("0, /*tp_str*/")
+		Output("PyObject_GenericGetAttr, /*tp_getattro*/")
+		Output("PyObject_GenericSetAttr, /*tp_setattro */")
+		
+		self.outputHook("tp_as_buffer")
+		self.outputHook("tp_flags")
+		self.outputHook("tp_doc")
+		self.outputHook("tp_traverse")
+		self.outputHook("tp_clear")
+		self.outputHook("tp_richcompare")
+		self.outputHook("tp_weaklistoffset")
+		self.outputHook("tp_iter")
+		self.outputHook("tp_iternext")
+		Output("%s_methods, /* tp_methods */", self.prefix)
+		self.outputHook("tp_members")
+		Output("%s_getsetlist, /*tp_getset*/", self.prefix)
+		self.outputHook("tp_base")
+		DedentLevel()
+		Output("};")
+		
+	def outputGetSetList(self):
+		if self.getsetlist:
+			for name, get, set, doc in self.getsetlist:
+				if get:
+					self.outputGetter(name, get)
+				else:
+					Output("#define %s_get_%s NULL", self.prefix, name)
+				if set:
+					self.outputSetter(name, set)
+				else:
+					Output("#define %s_set_%s NULL", self.prefix, name)
+					
+			Output("static PyGetSetDef %s_getsetlist[] = {", self.prefix)
+			IndentLevel()
+			for name, get, set, doc in self.getsetlist:
+				if doc:
+					doc = `doc`
+				else:
+					doc = "NULL"
+				Output("{\"%s\", (getter)%s_get_%s, (setter)%s_set_%s, %s}", 
+					name, self.prefix, name, self.prefix, name, doc)
+			DedentLevel()
+			Output("};")
+		else:
+			Output("#define %s_getsetlist NULL", self.prefix)
+			
+	def outputGetter(self, name, code):
+		Output("static PyObject *%s_get_%s(%s *self, void *closure)",
+			self.prefix, name, self.objecttype)
+		OutLbrace()
+		Output(code)
+		OutRbrace()
+		
+	def outputSetter(self, name, code):
+		Output("static int %s_get_%s(%s *self, PyObject *v, void *closure)",
+			self.prefix, name, self.objecttype)
+		OutLbrace()
+		Output(code)
+		Output("return 0;")
+		OutRbrace()
 
 class GlobalObjectDefinition(ObjectDefinition):
 	"""Like ObjectDefinition but exports some parts.