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On Tue, 27 Dec 2005 19:27:01 +0100 Carsten Lohrke <carlo@g.o> |
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wrote: |
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| - We speak about ebuilds, which are installed and need to be |
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| reinstalled. There is no version cycling (or I do not get what you're |
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| after, please explain in that case). |
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|
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foo-1.0: DEPEND="=foo-2.0" |
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foo-2.0: DEPEND="" |
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foo-3.0: DEPEND="=foo-1.0" |
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bar-1.0: DEPEND="=foo-1.0" |
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baz-1.0: DEPEND="=foo-2.0 bar" |
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moo-1.0: DEPEND="=foo-3.0 baz" |
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|
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# emerge moo -pv |
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|
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One solution for this particular case, assuming I didn't get confused |
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and screw it up: |
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|
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[n] foo-2.0 |
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[d] foo-1.0 |
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[n] bar-1.0 |
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[u] foo-2.0 |
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[n] baz-1.0 |
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[d] foo-1.0 |
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[u] foo-3.0 |
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[n] moo-1.0 |
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|
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Notice how we have to repeatedly upgrade and downgrade foo. |
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|
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| - Changed use flags will be processed by the normal dependency |
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| calculation of the ebuilds to be rebuilt which may lead to additional |
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| dependencies or blockers. It could also be that some ebuilds are |
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| installed, which do not exist in the repository anymore. |
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|
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Again, you can get cycling. This one's even nastier, if you have |
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various packages that DEPEND upon something built with [foo], various |
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packages that DEPEND upon something built with [!foo] and upgrade / |
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downgrade cycling on that package... |
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|
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| > you may find the PCP somewhat useful...) |
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| |
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| PCP - pretty colored potato? I don't know the abbreviation. Please |
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| explain it and whatelse I miss in your eyes. |
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|
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Post's Correspondence Problem. It's a proven general case unsolvable |
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problem that looks suspiciously similar to the general case "dependency |
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resolution with cycling" situation... |
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|
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-- |
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Ciaran McCreesh : Gentoo Developer (I can kill you with my brain) |
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Mail : ciaranm at gentoo.org |
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Web : http://dev.gentoo.org/~ciaranm |
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