Luis Zarrabeitia schrieb: > Personally, I like to use "is" with singletons. I find it easier to type and > read "if param is None" than "if param == None", but some python developers > dislike the first one because of the "dark magic" involved in knowing that > None is a singleton.
Testing for None is the only common case where you should *not* use == comparison. If you want to check if something is None then do "if something is None". Easy, isn't it? :] Look, what Python does for the various way (simplified): "if a == None:" -> "if a.__cmp__(None)" "if a is None" -> "if id(a) == id(None)" "if a:" -> "if a.__nonzero__()" / "if a.__len__()" Christian -- http://mail.python.org/mailman/listinfo/python-list
