On Tue, 15 Jul 2008 04:14:18 +0200
Marius Mauch <genone@g.o> wrote:
> As a result of Cardoes earlier mail we talked a bit about possible
> solutions in #gento-portage, and I suggested to let portage
> automatically inject the deps based on SRC_URI pattern matching.
> A mapping of extensions and their unpack deps would be kept in the
> tree (e.g. mapping '.tar.bz2' to '( app-arch/tar app-arch/bzip2 )'

Could do it just as an eclass...

inherit work-out-my-unpack-deps-for-me

In principle, there's nothing that can't be done on the ebuild side
here.

For the future EAPI side, you could require package managers to define
super-magic/package-manager-unpack-bzip2 etc for whatever they use to do
the unpacking, and to make it work with existing EAPIs, use || deps
with what existing package managers happen to use as the second item.
For current EAPIs it's no worse than the existing situation, where
ebuilds have to guess that package managers use 'app-arch/unzip' to
unpack zip files.

-- 
Ciaran McCreesh