[Python-Dev] Returning int instead of long from struct when possible for performance

[Tim Peters]

[Bob Ippolito]
> ...
> Unfortunately, this change to the struct module slightly alters the
> documented API for the following format codes: I, L, q, Q. Currently
> it is documented that those format codes will always return longs,
> regardless of their value.

I view that more as having documented the CPython implementation du
jour than as documenting the language.  IOW, it was a doc bug <0.5
wink>.

> I've prototyped this change on the trunk (behind a currently
> undefined PY_USE_INT_WHEN_POSSIBLE macro). The standard library test
> suite passes with this enabled, but it would break any doctests in
> third party code that check the result of an unpack operation with
> one of those format codes. Given the interchangeability of int and
> long, I don't foresee any other complications with this change.
>
> Thoughts?

+1, and for 2.5.  Even int() doesn't always return an int anymore, and
it's just stupid to bear the burden of an unbounded long when it's not
really needed.  As to doctest breakage, I'm wholly unsympathetic to
any doctest user except me, and I don't have any doctests that would
break.  So that's a total non-issue :-)