Hi, Maxim Cournoyer <[email protected]> writes:
> Hi Simon, > > Simon Tournier <[email protected]> writes: > >> Hi Maxim, >> >> Well, part of the message is in: :-) >> >> https://issues.guix.gnu.org/msgid/[email protected] > > Oh, a Mumi reference to a message ID! I didn't know it supported that, > cool! > >> On Thu, 04 May 2023 at 11:52, Maxim Cournoyer <[email protected]> >> wrote: >> >>> It seems a valid use case to have a channel that depends on an old Guix >>> version. Should this be supported? >>> >>> If I could for example use the following channel dependency file at the >>> level of the channel in a .guix-channel, to depend on an older Guix >>> revision: >>> >>> --8<---------------cut here---------------start------------->8--- >>> (channel >>> (version 0) >>> (dependencies >>> (channel >>> (inherit %default-guix-channel) >>> (commit "9ed65e6af77893b658a7159b091b5002892c2f95")))) >>> --8<---------------cut here---------------end--------------->8--- >> >> You want complete channel depends on a previous Guix, right? > > That's the idea I had yes, seeing that my channel won't work with any > newer Guix revision, I thought I should be able to declare that upfront > as a dependency, and have the channels mechanism take care of treating > all things relating to this channel via a Guix inferior. The benefit > above having to explain to users how to do this in a manifest as done in > [0] would be twofold: > > 1. The channel can simply be added and works out of the box, without > having users go through the hoops of configuring an inferior. > > 2. 'guix pull', if taught to translate a dependency on a past Guix into > an inferior, could use that at the time it runs ad avoid errors caused > by removed or moved packages in current Guix. > > [0] https://gitlab.com/Apteryks/sfl-guix-channel/-/blob/master/README.org > >> Somehow, it would become equivalent to this channels.scm >> >> (list (channel >> (name 'guix) >> (url "https://git.savannah.gnu.org/git/guix.git";) >> (branch "master") >> (commit >> "9ed65e6af77893b658a7159b091b5002892c2f95")) >> (channel >> (name 'sfl) >> (url "file:///tmp/sfl-guix-channel") >> (branch "master")))) >> >> and then run “guix pull && guix build sflvault-client” or: >> >> guix time-machine -C channels.scm -- shell sflvault-client >> >> >> Well, I do not know if it is desirable. Most of the time, I only want >> one specific package from one specific Guix revision. > > Not exactly equivalent to that channel file. In my idea (not thinking > about the technicalities/difficulties yet), the dependency on the Guix > channel would be made private to the package (my translating it to a > Guix inferior as mentioned above), instead of spilling into the global > package namespace (which I agree would be undesirable!). > > In other words, declaring a dependency on a prior Guix channel would > cause all derivations for packages in that channel to happen in a > corresponding Guix inferior. Does that make sense? > >> >>> As a workaround, I can define a 'python-pycryto*' in the channel itself, >>> although that's kind of silly because it can only be used with a Guix >>> inferior pegged to commit 9ed65e6af77893b658a7159b091b5002892c2f95, >>> which does contain 'python-pycryto'. >> >> Well, I do not know if we are using the time-travel the same way. :-) >> >> Considering this: >> >> (define-public foo >> (package >> (name "foo") >> (inputs >> (list bar) >> (list baz)))) >> >> Most of the time, I want to build ’foo’ using a recent Guix but that >> recent Guix removed ’bar’ so I want to pick it up from an inferior. >> And let say I want ’baz’ from another Guix revision because some >> specific version of ’baz’ is required for building ’foo’. >> >> Basically, I am tempted to define the symbol ’bar’ and ’baz’ in my >> channel and bind them to some inferior packages (here from 2 Guix >> revisions). > > Interesting. So using inferiors inside your channel does work in > general, contrary to experiments made with the sfl-guix-channel in the > other thread? The discussion has long died, and so has my original use case, but based on what you had written I guess it could have been possible to add code to my channel file so that all packages would have been computed through an inferior. I'll close this for now. -- Thanks, Maxim
