Re: [gentoo-dev] add global useflag: webkit

[Michał Górny]

On Mon, 07 May 2012 20:58:18 -0700
Zac Medico <zmedico@g.o> wrote:

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> On 05/07/2012 08:50 PM, Michał Górny wrote:
> > On Mon, 07 May 2012 14:41:33 -0700 Zac Medico <zmedico@g.o>
> > wrote:
> >
> >> On 05/07/2012 01:43 PM, Michał Górny wrote:
> >>> On Mon, 07 May 2012 13:24:31 -0700 Zac Medico
> >>> <zmedico@g.o> wrote:
> >>>
> >>>> On 05/07/2012 12:18 PM, Ulrich Mueller wrote:
> >>>>>>>>>> On Mon, 7 May 2012, Ciaran McCreesh wrote:
> >>>>>
> >>>>>> I propose:
> >>>>>
> >>>>>> REQUIRED_USE="== ( qt webkit )"
> >>>>>
> >>>>> But this just means that the ebuild has redundant USE
> >>>>> flags, so one of them shouldn't be in IUSE, in the first
> >>>>> place.
> >>>>
> >>>> It serves to convey meaning, such that a user who has
> >>>> disabled the qt USE flag will get a meaningful prompt if that
> >>>> flag is required for webkit support. This kind of information
> >>>> could be useful to some people, and it may be preferable to
> >>>> having a separate webkit-qt flag.
> >>>
> >>> If 'qt' flag is required for webkit support, it's 'webkit? ( qt
> >>> )'.
> >>
> >> What if '!webkit? ( !qt )' also applies though? As an alternative
> >> to listing both constraints separately, you could combine them as
> >> '^^ ( webkit !qt )', or add support for '== ( qt webkit )' to
> >> make the expression easier to read.
> >
> > Then it's pointless to have the 'webkit' flag which doesn't
> > control anything.
>
> Generalize the discussion to be about two abstract flags "x" and "y"
> that have the same kind of relationship, where each one actually does
> control something, but the two features are intertwined in a
> particular package such that they must both be enabled or disabled in
> unison.

Then please show me an example of that.

-- 
Best regards,
Michał Górny