On Fri, Feb 15, 2008 at 12:52 PM, Phillip J. Eby <[EMAIL PROTECTED]> wrote: > At 11:41 AM 2/15/2008 -0800, Guido van Rossum wrote: > >On Fri, Feb 15, 2008 at 10:26 AM, Phillip J. Eby > ><[EMAIL PROTECTED]> wrote: > > > > I've never actually encountered a usecase for keeping a standard > > > weakref to a standard bound method, though. It's pretty useless, > > > because bound methods are nearly always immediately disposed of, and > > > there's no logical place (or reason) to store them. So, Nick's query > > > is (in effect), can we either: > > > > > > 1. make ref(method) create a "weak method" instead, or > > > > > > 2. make ref(method) an error instead of useless behavior that gives > > > you the illusion of working code > > > >#2 is easily implemented (just remove the machinery to support weak > >refs from the bound method object) but the question is, will it break > >anybody's code -- and if so, do we care enough to break it? (In Py3k, > >that is.) > > It's hard to imagine what could be using it, but I guess it's possible. > > > > >#1 isn't so easy in terms of how you'd implement it -- I don't think > >the weakref.ref() call currently has a way to customize what kind of > >thing you get back. I'd be open for a patch containing working code > >that can be generalized to other cases. > > Well, one could allow for a __weaken__ method that would be called if > present, instead of the default constructor. The part I'm not > immediately sure of is where to call it *from*, so that you can still > subclass weakref.ref and not end up in a strange delegation loop. I > guess you could call it if and only if weakref.ref.__new__ was passed > weakref.ref as the class to construct.
I think str() does this. But maybe given how rare the use case is, it would be easier to just create a custom class in weakref.py that does what Nick requested. -- --Guido van Rossum (home page: http://www.python.org/~guido/) _______________________________________________ Python-3000 mailing list Python-3000@python.org http://mail.python.org/mailman/listinfo/python-3000 Unsubscribe: http://mail.python.org/mailman/options/python-3000/archive%40mail-archive.com
