[Python-Dev] folding cElementTree behind ElementTree in 3.3

[Nick Coghlan]

On Mon, Feb 20, 2012 at 9:43 PM, Xavier Morel <python-dev at masklinn.net> wrote:
> I'm not sure that's much of an issue, Element (and most of the top-level
> utility "constructors") are documented as being frontend interfaces with
> no specific type of their own, and indeed they are simply functions in
> lxml, just as they are in cElementTree.
>
> Others will probably disagree, but as far as I am concerned these can stay
> functions, avoid issues when switching to lxml or between ElementTree and
> lxml (from one project to the next).

For a similar situation (only the other way around), we're probably
going to add a pure Python variant of functools.partial as a
staticmethod, while the C version is a callable extension type. (see
http://bugs.python.org/issue12428)

Basically, if something is just documented as being callable without
subclassing or instance checks being mentioned as supported in the
docs, it can be implemented as either a type or an ordinary function,
or pretty much any other kind of callable without being deemed an API
change (obviously that's not a free pass to go make such
implementation changes without a compelling reason, but C vs Python
often *is* such a reason).

Cheers,
Nick.

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