Gentoo Archives: gentoo-dev

From: NP Hardass <np.hardass@×××××.com>
To: gentoo-dev@l.g.o, gentoo-portage-dev@l.g.o
Subject: [gentoo-dev] RFC: [Future EAPI] [Feature Request] RECOMMENDED_USE
Date: Fri, 06 Feb 2015 16:20:31
Message-Id: CA+42iEtk2-05J+nbdJkDb1a7TEF0Ba=8=TKaWXz3dvapPuimiQ@mail.gmail.com
1 https://bugs.gentoo.org/show_bug.cgi?id=539124
2
3 Excerpt:
4 Primarily, the idea here that a maintainer may want to have IUSE="foo bar"
5 and bar is recommended if foo is selected. Currently, the only way to
6 recommend a use flag is IUSE="+baz" This doesn't work with the above
7 mentioned example because IUSE="foo +bar" would recommend bar regardless of
8 whether foo is selected or not.
9
10 For backwards compatibility, the IUSE + syntax can be maintained, but
11 alternatively, it may be simpler, and make more sense to have something
12 like:
13 IUSE="foo bar baz"
14 RECOMMENDED_USE="
15 foo? ( bar )
16 baz"
17 So in this example:
18 IUSE="baz"
19 RECOMMENDED_USE="baz"
20 is equivalent to IUSE="+baz"
21
22 The original inspiration for this idea was the following,
23 app-emulation/wine works both with and without X. Most users who use X
24 would most likely want the USE flags lcms and xcomposite, but setting them
25 + in IUSE makes compiling wine with -X more complicated, as every flag that
26 + just for X users would have to be unset for non-X users. The above
27 system simplifies this by only setting + on lcms and xcomposite if X is set.
28
29 Alternatively, other names could be used, like DEFAULT_USE instead of
30 RECOMMENDED_USE, but that is a side note to the primary point.
31
32 Any thoughts on the idea would be greatly appreciated, and thank you in
33 advance for your time.