Re: [gentoo-user] Re: Prevent depclean from removing Python-2.6?

[Alan McKinnon <alan.mckinnon@gmail.com>]

Apparently, though unproven, at 17:13 on Tuesday 10 May 2011, Grant Edwards 
did opine thusly:

> > I think the issue happens because portage does not take eselect
> > choices into account when building it's dep graph, it only uses the
> > DEPENDS in ebuilds.
> 
> Apparently so.  It seems like it ought to pay attention to eselect. 
> If I've explicitly configured my system to use 2.6 instead of 2.7,
> removing 2.6 doesn't seem like a good thing...

There's one more wrinkle though:

portage, ebuilds and EAPI are all portable to other systems (funtoo etc) 
whereas eselect is very gentoo-specific.

So putting gentooism support into portage would be counter-productive.

A real solution would require some kind of generic statement in ebuilds that 
would allow for optional dependencies. I haven't thought this completely 
through, but maybe something like the following:

- A new keyword in ebuilds to indicate packages with soft deps
- A new file format that lists these deps currently in use
- Tools like eselect could update this file as they adjust user preferences

This way, portage would have additional info available about unusual packages 
still in use when --depclean runs.


-- 
alan dot mckinnon at gmail dot com