[Python-Dev] Accept just PEP-0426

Vinay Sajip vinay_sajip at yahoo.co.uk
Tue Nov 20 16:16:25 CET 2012

Daniel Holth <dholth <at> gmail.com> writes:

> If you don't have Provides-Dist, then distribute must continue to bundle an
> extra .egg-info directory to emulate the feature. This is more than enough
> justification for me. Name: is essentially an alias for Provides-Dist: (or
> vice-versa) so there is no such thing as a single-valued Provides-Dist. Having
> two names for a package is just as complicated as having twenty.

I'm not so sure. In the case of two names, it could be assumed that one was a
fork of the other (as in the specific cases of distribute/setuptools, or PIL/
Pillow). You cannot reasonably make this assumption if you have twenty entries
in your Provides-Dist.

> You should not implement Provides-Dist by searching for every Provides-Dist:
> name on PyPI.

I wasn't seriously suggesting that this approach be taken - merely pointing out
that Provides-Dist isn't of much use in a metadata index.

> should only use it when deciding whether to download setuptools when distribute
> is already installed and a package depends on setuptools.The bundling term was
> bad wording on the part of the PEP. No one should ever include non-renamed
> copies of other dists in their dists "import six" vs. "import django.util.six".
> I've suggested a new wording in this thread.

So apart from the setuptools/distribute and PIL/Pillow scenarios, what are the
scenarios where you would have 3 or more values in Provides-Dist? If they are
e.g. a bundled SQLAlchemy, why would that be preferable to an entry in


Vinay Sajip

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