[Python-Dev] PEP 408 -- Standard library __preview__ package

[Antoine Pitrou]

Hello Philippe,

On Fri, 27 Jan 2012 17:09:08 +0100
Philippe Fremy <phil at freehackers.org> wrote:
> 
> According to the PEP, the interface may change betweeen __preview__ and
> final inclusion in stdlib. It would be unwise as a developer to assume
> that a program written for the preview version will work correctly in
> the stdlib version, wouldn't it ?
> 
> I would use your "normal" incantation only after checking that no
> significant API change have occured after stdlib integration.
> 
> By the way, if as Antoine suggests, the package remain available in
> __preview__ even after it's accepted in the stdlib, how is the user
> supposed to deal with possible API changes ?

The API *may* change but it would probably not change much anyway.
Consider e.g. the "regex" module: it aims at compatibility with the
standard "re" module; there may be additional APIs (e.g. new flags),
but whoever uses it with the standard "re" API would not see any
difference between the __preview__ version and the final version.

cheers

Antoine.