[Python-Dev] PEP 352 Transition Plan

[Raymond Hettinger]

> > Why would a
> > release allow catching something that cannot be raised?  I must be
> > missing something here.
> 
> So conforming code can catch exceptions raised by not-yet conforming
code.

That makes sense.

What was the rationale for pushing the deprecation of __getitem__ and
args back to Py2.8?  Is the there a disadvantage for doing it earlier?
On the flip side, is there any reason it has to be done at all prior to
Py3.0?  That change seems orthogonal to the rest of the proposal and has
its own pluses and minuses (simplification on the plus-side and
code-breakage on the minus-side).  

FWIW, the args tuple does have a legitimate use case as one solution to
the problem of exception chaining (keeping the old info intact, but
adding new info as an extra field):

   try:
	raise TypeError('inner detail')
   except TypeError, e:
	args = e.args + ('outer context',)
	raise TypeError(*args)


Raymond