Re: [gentoo-dev] Re: sub-slots (for EAPI 5)

[Fabian Groffen]

On 07-09-2012 20:36:02 +0100, Ciaran McCreesh wrote:
> The correct fix for "not needing to rebuild" stuff is to SLOT libraries
> like crazy, and have a SLOT per thing-we-don't-call-ABI. This then
> needs := dependencies, so that packages can say "and remember which
> SLOT I was built against".
>
> However, there are some packages that cannot easily be SLOTted to the
> degree that we'd like. This is where sub-SLOTs come in. Given
> sub-SLOTted packages dep:1/a and dep:1/b, this says "I'd like to have
> slots 1a and 1b, but it's too difficult to allow 1a and 1b to be
> installed at the same time".
>
> So suppose the user has pkg with a dependency upon dep, with slot 1 and
> a := operator. They install pkg when dep:1/a is installed. The user
> then installs dep:1/b. In an ideal world, dep:1/a would remain
> installed in parallel with dep:1/b, but your friendly Gentoo developers
> have decided it's not worth their time to allow this. Thus, dep:1/a has
> to be uninstalled to allow dep:1/b to be installed. But this would
> break pkg, since pkg needs dep:1/a. However, a clever dependency
> resolver can note that reinstalling pkg would fix it, since dep:1/b
> also satisfies pkg's slot 1 := dependency (but not the locked 1/a
> dependency that the installed version of pkg has picked up).

Thanks.  It seems we're there.  At last.


-- 
Fabian Groffen
Gentoo on a different level