Re: [gentoo-dev] Re: Multiple implementations shouldn't block Gentoo's progress. Stabilize package combinations?

[Samuli Suominen <ssuominen@gentoo.org>]

On 09/08/13 11:46, Tom Wijsman wrote:
> On Fri, 09 Aug 2013 08:39:20 +0300
> Samuli Suominen <ssuominen@gentoo.org> wrote:
>
>> On 09/08/13 04:05, Zac Medico wrote:
>>
>>> This seems like a possible applicatio for "mix-in" profiles like
>>> Funtoo uses:
>>>
>>>     http://www.funtoo.org/wiki/Flavors_and_Mix-ins
>
> Thanks, that definitely looks interesting; reading it I actually would
> love to see this implemented to ease the user from switching from one
> to another init system, or whatever needs switching in the future.
>
>> What if eg. profiles/targets/desktop would have sub directory
>>
>> profiles/targets/desktop/systemd which would have a 'parent' of '..'
>> with USE="-consolekit systemd" and more importantly, the could-be
>> kludge to setup the /usr-move, the could-be environment variable to
>> disable functionality of gen_usr_ldscript...
>>
>> profiles/targets/desktop/gnome with 'parent' of '..' and
>> '../../systemd' ...
>
> Let me stop you right here; part of this idea came to mind yesterday,
> but I saw a flaw in it so I did not suggest it:
>
>    What if a certain profile needs to support two such profiles (eg.
>    upstart and systemd) that have conflicting choices (eg. one profile
>    lists -systemd, the other systemd); then you can no longer list both
>    as a parent as they will simply clash and make conflicting changes.

Sure you can, simply by counter effecting the parent as suggested, if 
parent lists '-systemd' then the actual profile can set 'systemd'
Plus it would be the main systemd sub profile that would be 'top most' 
in the parent file, causing it to enable 'systemd' even if the 'second 
top most' disables it

> Of course this isn't a problem for this situation, but it may become a
> problem in a future situation if we're going to follow this practice;
> that's why I think now that mix-in profiles fit the purpose better.

I'm not seeing the problem...