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