Ciaran McCreesh wrote: > Is the less expressive solution you're describing still useful enough > to make it worthwhile? When we were doing this for Exherbo, we > identified five types of inter-use-flag dependency: > Actually, I said in my email I was looking for opinions about the feature not really about the syntax. It was just an example but as no-one jump to say it was useless and stupid, let's try with a clearer syntax.
> * if a then b > IUSE_REQUIREMENTS="a? ( b )" > * if a then not b > IUSE_REQUIREMENTS="a? ( -b )" > * at least one of a b c, possibly only if d > IUSE_REQUIREMENTS="d? ( || ( a b c ) )" > * exactly one of a b c, possibly only if d > IUSE_REQUIREMENTS="d? ( || ( a b c ) ) a ? ( -b -c ) b ? ( -a -c ) c? ( -a -b )" > * at most one of a b c, possibly only if d > IUSE_REQUIREMENTS="d? ( a? ( -b -c) b? ( -a -c ) c? ( -a -b) )" if needed we can add IUSE_REQUIREMENTS="!d? ( -a -b -c)" > Does Gentoo make use of all of these, and are there any cases that the > above doesn't cover? How would you express each of the above using > USE_REQUIREMENTS? > > From a package manager perspective, it's much easier to give good > advice to the user if we're told by the ebuild exactly what's going on. > So I think we can satisfy all use cases with the classic Gentoo syntax even if new operators could be appreciated ;) -- Mounir
