[Distutils] .egg-info metadata

[PJ Eby]

On Thu, Sep 20, 2012 at 4:53 PM, Donald Stufft <donald.stufft at gmail.com> wrote:
> On Thursday, September 20, 2012 at 4:24 PM, Daniel Holth wrote:
>
> It's probably a style thing, but I like to distribute this information
> out-of-band. So as the author of foopackage (an application) I list
> all the requirements and their requirements and where they can be
> found, including git+http://github urls and so forth. I'm sure this
> has all been discussed to death over the last 6+ years.
>
> For what it's worth I agree with you here.

As a practical matter (and practicality beats purity), it's sometimes
necessary to provide this information in order to depend on packages
that aren't cataloged in PyPI, or when third-party build support is
required, and your goal is to offer a library or application which
itself is used as a dependency.

That is, if project A depends on project B, which depends on C, which
is not on PyPI, then A cannot simply depend on B without *copying*
this "out of band" information, propagating a maintenance burden.
Dependency links work around this problem (among others).

So, IMO, this is actually a crucial part of making a composable
dependency system in *practice*, even if it is not required in
*theory*.