Re: [gentoo-user] Is Gentoo wiping out Gtk 2 support from packages that support it?

[Albert Hopkins <marduk@letterboxes.org>]

On Friday, July 8 at 17:19 (+0200), Alan McKinnon said:

> On Friday 08 July 2011 09:14:36 Albert Hopkins did opine thusly:
> > On Friday, July 8 at 13:11 (+0100), Stroller said:
> > > Taking a look at this bug today, is there any reason why the
> > > ebuild shouldn't simply RDEPEND="x11-libs/gtk+" (i.e. remove
> > > the explicit dep on gtk3), detect what version you have
> > > installed on your system and then either run --enable-gtk3 or
> > > --enable-gtk2 during src_configure(), depending upon which
> > > you're using?
> > 
> > ebuilds generally don't do this, because it is bad.  What you have
> > and what you want aren't necessarily the same thing.  Consider:
> > 
> >       * You don't yet have any gtk installed
> >       * You have gtk2 but actually *want* the gtk3 version, so you
> > want the ebuild to pull in gtk3 (or vice versa)
> >       * You have both gtk2 and gtk3 installed.
> >       * You have gtk installed, but don't want gtk support for a
> >         particular package (if gtk support is optional for that
> >         package).
> 
> easy.
> 
> Two USE flags: gtk2 and gtk3
> 
> in ebuild:
> 
> DEPEND="
>     gtk2? (x11-libs/gtk+:2)
>     gtk3? (x11-libs/gtk+:3)
> "
> 
> in src-configure() write the code such that it establishes a 
> precedence
> 
> If both flags are set, build against gtk+:3
> If only one flag is set, build against that toolkit
> If no flags are set, do something appropriate.
> 

You mean like what they did with portage and python2/3?

Well, there was bugs in that (I reported 1 or 2 bugs myself).  It works
now (depending on your expectation of "works" but is very ugly.

> IIRC, it is frowned upon to have conditionals in DEPENDS based on USE 
> flags so the above is best - take the small hit on disk space if both 
> are set and gtk+:2 is used nowhere else (highly unlikely for quite a 
> while still)
> 
They could do that.. I don't see it happening though.

I didn't want to comment on this thread (having been on both sides of
the fence).  But I will say this.  The best thing about Gentoo is it's a
"meta-distribution".  It gives you more control and more ease to do
things "your" way.  I think people should learn to take more advantage
of the latter.  I do.