[Python-Dev] q about __dict__

Stepan Koltsov yozh@mx1.ru
Tue, 13 Aug 2002 17:03:21 +0400

Hi, Guido, other python developers and other subscribers :-)

Anybody, please explain me, is this a bug? :

=== begin ===
class Dict(dict):
	def __setitem__(*x):
		raise Exception, "Please, do not touch me!"

class A:
	def __init__(*x):
		self.__dict__ = Dict()

A().x = 12
===  end  ===
doesn't raise Exception, i. e. my __setitem__ function is not called.

Patching that is simple: in Objects/classobject.c need to replace
	PyDict_SetItem -> PyObject_SetItem
	PyDict_GetItem -> PyObject_GetItem
	PyDict_DelItem -> PyObject_DelItem
and maybe something else (not much).

Overhead is minimal, and as bonus python gets ability of assigning
object of any type (not inherited from dict) to __dict__.


Somethimes I want to write strange classes, for example, class with
ordered attributes. I know, that it is possibe to implement this
redefining class attributes __setattr__, etc., but setting __dict__
looks clearer.

Thanks for reading this letter till the end ;-)

mailto: Stepan Koltsov <yozh@mx1.ru>