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

[Zac Medico]

On 05/07/2012 09:07 PM, Michał Górny wrote:
> 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.

I don't see any offhand. I guess it's fairly uncommon, or non-existent.
-- 
Thanks,
Zac