[Jeremy Hylton]
On Wed, 2004-01-21 at 20:24, François Pinard wrote:
If there is no base class, then "if there's a global variable named __metaclass__, it is used." So my guess would be that adding a mere
__metaclass__ = type
in global scope for a module would make all classes be "new-style", without the need to subclass them from object explicitly.
Unless you define a class that inherits from a base class defined in another module.
I thought about this of course. This is no problem in our case, since these other modules will have their `__metaclass__ = type' themselves.
I prefer to inherit from object, because it is more explicit, and avoids possible confusion when some classes have classic bases.
A `__metaclass__ = type' at the beginning of a module is explicit enough to my eyes. If I can demonstrate that this does not harm, it will become a convention here to include this line in each and every module for all in-house projects, and we should be done with classic classes. Unless we sub-class classic classes from the Python library, I do not know how frequently we do that. By the way :-), I presume there are plans for the Python library to progressively switch to new-style classes whenever possible? If not, should they be? -- François Pinard http://www.iro.umontreal.ca/~pinard