[Distutils] [Catalog-sig] Prototype setuptools-specific PyPI index.

["Martin v. Löwis"]

>> > Because if case actually made a difference, we couldn't have both
>> > packages installed in the same directory, could we?
>>
>> Right. However, there is a difference between case-insensitive,
>> and case-preserving.
> 
> I don't understand your statement here, nor what is supposed to follow
> from it.

Clearly, on a case-insensitive file system, project names differing
only in case cannot coexist. That doesn't mean that all references
to the project should be case-normalized (e.g. lower-cased).

So even if project names compare case-insensitive, there still
should (could) be a "right" spelling, the one that the package
author wants to see. This is the spelling that others then should
use.

So I still don't see why the file names on disk have any effect
on the lookup setuptools do to the index.

> Jim's objection was that if it's possible to get case-correction from
> the index, people will declare setup.py dependencies with incorrect
> case, leading to other packages having indirect dependencies with
> incorrect case, leading to lots of package index lookups.

I don't think that was his objection. IIUC, he complains about
incorrect spellings as bad, period - regardless of whether they also
have a performance effect. It's like spelling your name "Philipp" -
that's a bad thing to do, independent of whether it also makes you
harder to find (which it actually doesn't, thanks to Google).

> This objection is relevant only to requirements which differ from the
> actual project name only by their case.  A non-registered package lookup
> is going to fail no matter what, and thus isn't going to wind up in a
> setup.py without a dependency_links specifier that will prevent it being
> looked up in the package index to begin with.

Right. However, if setuptools would stop making case insensitive
lookups to the index, lookups to unregistered packages would become
more efficient.

Regards,
Martin