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On 11/08/2014 10:52 PM, Jauhien Piatlicki wrote: |
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> 08.11.14 22:47, hasufell написав(ла): |
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>> On 11/08/2014 10:30 PM, Rich Freeman wrote: |
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>>> On Sat, Nov 8, 2014 at 2:48 PM, hasufell <hasufell@g.o> wrote: |
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>>>> On 11/08/2014 08:32 PM, hasufell wrote: |
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>>>>>> Sorry to chime in like that but if you don't mind, I'd like to ask for a |
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>>>>>> real-life example for badly declared dependencies with a few words why |
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>>>>>> those are bad and how to make them actually better? |
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>>>>>> |
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>>>>> |
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>>>>> from dev-haskell/hashtables (note "hashtables" != "hashable"): |
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>>>>> || ( ( >=dev-haskell/hashable-1.1:=[profile?] |
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>>>>> <dev-haskell/hashable-1.2:=[profile?] ) |
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>>>>> ( >=dev-haskell/hashable-1.2.1:=[profile?] |
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>>>>> <dev-haskell/hashable-1.3:=[profile?] ) |
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>>>>> ) |
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>>>>> |
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>>>>> Latest stable version of dev-haskell/hashable is 1.2.1.0. |
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>>>>> On a stable system (arch) the paludis dep-solver will try to match the |
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>>>>> first group first and realize that there is also a stable version |
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>>>>> 1.1.2.5 that matches that group. At that point there is a correct |
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>>>>> solution, but since that involves downgrading a package, it will require |
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>>>>> user-intervention, because it may not be what the user wants. |
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>>>>> (this is the easy scenario... if downgrading causes blockers, you get |
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>>>>> much more interesting output) |
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>>>>> |
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>>>> |
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>>>> To be more specific... it is assumed that hashable-1.2.1.0 is already |
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>>>> installed. Every time the dep solver runs through those packages without |
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>>>> specifying what you want, you will hit the downgrade-problem. |
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>>> |
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>>> I'm missing the problem. The package requires one of two ranges of |
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>>> hashable versions. One of them is already installed. The dependency |
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>>> is satisfied. |
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>>> |
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>> |
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>> The one that is installed (1.2.1.0) is *excluded* by the first group, |
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>> but there is a valid version that fits instead (1.1.2.5). |
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>> |
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>> That's the point where the assumptions start about what the depstring |
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>> means and what the user wants. |
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>> |
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> |
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> So the problem is only with intervals? First of all, maintainer would specify higher interval first here and it would solve a problem with possible downgrading. |
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I have a feeling that this is an assumption as well. PMS just says this |
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is an 'any-of' group. There is not a single word about the processing |
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order of these specs or which one to prefer, in which case some is |
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better than the other and so on. |
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