[Python-Dev] breaking list.append()

Paul Prescod paul@prescod.net
Tue, 29 Feb 2000 18:56:33 -0800

Software configuration management is HARD. Every sudden backwards
incompatible change (warranted or not) makes it harder. Mutli-arg append
is not hurting anyone as much as a sudden change to it would. It would
be better to leave append() alone and publicize its near-term removal
rather than cause random, part-time supported modules to stop working
because their programmers may be too busy to update them right now.

So no, I'm not stepping up to do it. But I'm also saying that the better
"lazy" option is to put something in a prominent place in the
documentation and otherwise leave it alone.

As far as I am concerned, a formal warning-based deprecation mechanism
is necessary for Python's continued evolution. Perhaps we can even
expose the deprecation flag to the programmer so we can say:

if deprecation:
	print "This module isn't supported anymore."

if deprecation:
	print "Use method FooEx instead."

If we had a deprecation mechanism, maybe introducing new keywords would
not be quite so painful. Version x deprecates, version y adds the
keyword. Mayhap we should also deprecate implicit truncating integral
division while we are at it...

 Paul Prescod  - ISOGEN Consulting Engineer speaking for himself
"The calculus and the rich body of mathematical analysis to which it
gave rise made modern science possible, but it was the algorithm that
made possible the modern world." 
        - from "Advent of the Algorithm" David Berlinski