Re: more package transformations: overrides

[Ludovic Courtès]

Hi,

Ricardo Wurmus <rekado@elephly.net> skribis:

> when using package transformations the command line can become crowded
> very quickly.  Sometimes I would like to be able to provide a file
> containing a set of alternative packages that are used recursively in
> the package dependency graph, as some sort of override.

The long-command-line issue can be addressed by using a manifest,
possibly generated (info "(guix) Writing Manifests").

> What do you think about extending package transformations to allow for
> reading override packages from a file?  The replacements would happen by
> matching package names, so a package named “python-pytorch” in my
> overrides file would replace the original “python-pytorch” package in
> the input graph.  All these packages would be applied as overrides
> together.

Could this override mechanism be itself a package transformation option?
:-)

  guix shell python-pytorch \
    --with-overrides=$HOME/.config/guix/my-stuff.scm

Perhaps ‘--with-overrides’ without any argument would pick a default
file name.

It would be implemented in terms of ‘package-input-rewriting/spec’ I
suppose.

Ludo’.