Re: [gentoo-dev] Actions of python team, especially Arfrever wrt python eclass and python-3*

[Graham Murray <graham@gmurray.org.uk>]

Thomas Sachau <tommy@gentoo.org> writes:

> Since python-3* is currently useless and not required for any package, the dependency should by
> default only pull in python-2* like this:
>
> =dev-lang/python-2*
>
> With that, the default way would not pull in a package, which is not needed or used. And if there
> will be any package, which really requires python-3*, it simply requests it in (R)DEPEND of the
> ebuild, which then would overwrite the default value of the eclass and pull in python-3*.

That would not work. For example if package 'bar' supports both python-2
and python-3, your mechanism will only build in python-2 support. That
is fine until package 'foo' comes along which uses 'bar' but also
requires python-3 - thus not only must python-3 be pulled in as a result
of foo's (R)DEPEND but also 'bar' must be rebuilt with python-3 support.

This could be done by adding python2 and python3 USE flags to packages
which support both and only have python2 enabled by default. Then 'foo'
could have a conditional (R)DEPEMD on 'bar[python3]', but that would
require the user to change the USE flags whereas the current system
handles everything automatically.