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On Mon, Feb 23, 2009 at 7:53 AM, Ciaran McCreesh |
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<ciaran.mccreesh@××××××××××.com> wrote: |
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> On Mon, 23 Feb 2009 08:43:09 -0700 |
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> Steve Dibb <beandog@g.o> wrote: |
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>> Plus, I don't really grasp the whole "we have to source the whole |
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>> ebuild to know the EAPI version" argument. It's one variable, in one |
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>> line. Can't a simple parser get that and go from there? |
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> |
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> Not true. This is entirely legal: |
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> |
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> In pkg-1.ebuild: |
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> |
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> EAPI="${PV}" |
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> printf -v EAPI '%s' 4 |
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> inherit foo |
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> EAPI="2" |
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> |
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> In foo.eclass: |
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> |
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> EAPI="3" |
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|
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This is not legal, the devmanual[1] explicitly states that it is not |
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legal to set EAPI in an eclass. If it was you would have an open and |
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shut case for g55 (since you could set EAPI based on PV in an eclass |
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and then inherit the eapi; requiring a bash parser). But its illegal, |
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which makes your argument harder. |
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|
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A bad argument is EAPI based on some PV logic that you can copy across |
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ebuilds that differ by version; which would fall into 'stupid' in my |
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book. |
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|
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[1] http://devmanual.gentoo.org/ebuild-writing/eapi/index.html |
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|
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> |
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> And in this case, the package manager has to know that EAPI=2, and it |
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> has to use EAPI 2's behaviour for performing the inherit. |
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> |
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> In fact, it gets worse if you consider that future EAPIs will probably |
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> allow per-package eclasses. So you could end up with this crazy |
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> situation: |
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> |
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> In pkg-1.ebuild: |
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> |
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> require pkg |
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> |
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> In cat/pkg/pkg.eclass: |
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> |
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> EAPI="3" |
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> |
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> In global pkg.eclass: |
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> |
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> EAPI="2" |
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|
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Also illegal, but I assume here you intend to change the legality of |
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things in your weird future example. |
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|
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> |
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> So here you can't even use a faked pre-source EAPI. If you assume EAPI |
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> 0 beforehand, the global pkg.eclass will be used, so EAPI will end up |
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> as 2. But if you assume EAPI 3 beforehand, the per-pkg eclass will be |
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> used, so the EAPI will end up as 3. |
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> |
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> It gets even crazier if you put EAPI="2" in the per-pkg eclass and |
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> EAPI="3" in the global one instead... |
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> |
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> And whilst this is clearly a deliberate example of how to create |
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> craziness, the only difference between this and the real world is that |
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> the craziness is obvious here. The current rules really are this |
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> complicated, and we can't retroactively fix them. |
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> |
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> -- |
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> Ciaran McCreesh |
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> |
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