Re: [gentoo-dev] USE variables in SRC_URI

[Dan Armak <danarmak@gentoo.org>]

> You actually can't do it that way, because it will cause incomplete digests
> to be generated if "foo" isn't set in USE.  The new system auto-adjusts so
> that maintainers always generate correct digests, but normal users only
> need to download the files they need.

As I understand this, you download everything if MAINTAINER is set. Then, I 
suppose, you also get a ${A} with all the files you downloaded and you unpack 
them all. 

Normally this isn't a problem, but in theory: an ebuild might use ${A} to do 
some "for x in" etc. processing to avoid putting use flag tests in both 
SRC_URI and every function. (Together with DEPEND and RDEPEND there are 5 
places where you typically query use flags, plus the 4 pkg_ functions.) This 
is a very rare case, but after working with eclasses I'm used to thinking in 
a generic way about these things.

So: I propose that to make ebuilds behave the same way regardless of 
MAINTAINER, we should set $A the proper way, and download all files anyway.

Perhaps you think this issue isn't very important; I admit I never wrote or 
saw an ebuild that behaved like this. But they might.

-- 

Dan Armak
Gentoo Linux Developer, Desktop Team
Matan, Israel