[Python-Dev] Re: [Python-checkins] python/dist/src/Lib formatter.py,1.20,1.21 ftplib.py,1.69,1.70 gettext.py,1.13,1.14 hmac.py,1.5,1.6

Guido van Rossum guido@python.org
Sun, 02 Jun 2002 16:56:39 -0400

[Andrew MacIntyre commenting on Raymond H's changes from "if x" to
"if x is not None"]
> You have in fact changed the semantics of this test with your change.
> In the case where file = '', the original would fall through to the
> elif, whereas with your change it won't.

The question is whether that's an important change or not.  Raymond
has changed the semantics in every case where he made this particular
change.  Usually that's fine.  Occasionally it's not.

> It concerns me that your extensive changes have introduced some
> unexpected traps which won't be sprung until 2.3 is released.

Me too.  I think 99% of the changes were "right", but without looking
at actual use cases much more we won't know where the 1% mistakes are.

I think it's okay to do this (because of the 99%) but we should be
aware that we may be breaking some code and willing to revert the
decision in some cases.  I'm not sure how we can test this enough
before 2.3 is released -- surely the alphas won't shake out enough.

--Guido van Rossum (home page: http://www.python.org/~guido/)