[Python-Dev] Adding PEP consistent aliases for names that don't currently conform

[Nick Coghlan]

Guido van Rossum wrote:
> On Wed, Mar 25, 2009 at 5:46 AM, Nick Coghlan <ncoghlan at gmail.com> wrote:
>> Having helped with that kind of rename once (and for a relatively small
>> API at that), I'd want a *really* compelling reason before ever going
>> through it again - it's messy, tedious and a really good way to burn
>> volunteer time without a great deal to show for it at the end.
> 
> My first response was "in hindsight we shouldn't have done this."

Even in hindsight, I think our reasons for providing a PEP 8 compliant
threading API are sound. But the experience still makes me cautious of
doing it again.

> But
> we moved a bunch of other modules around too (urllib, http, db, I
> forget what else) and I think those worked out well.

For everything else, we just changed the module name or location. The
test suite is pretty good at finding any relevant imports that need to
be fixed, and 2to3 is also pretty good at handling them for third party
code. The threading module was different in that we actually wanted to
change the API of the module itself rather than just where to find it.

> Why was threading
> particularly unpleasant? (An no, this isn't a rhetorical question or a
> retort. I'm just curious -- I have the same feeling but can't pin it
> down.)

I think the main thing that may be putting me off is the amount of
energy that went into deciding whether or not to emit Py3k warnings or
DeprecationWarning or PendingDeprecationWarning for use of the old
threading API. The difficulty of that decision strongly flavours my
recollection of the whole process even though the final solution chosen
was quite simple (maintain the two APIs in parallel, with a couple of
notes in the documentation about the situation).

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
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