Re: Package inputs in manifests

[zimoun <zimon.toutoune@gmail.com>]

Hi,

On Sun, 17 Nov 2019 at 11:35, Ludovic Courtès <ludo@gnu.org> wrote:

> You’re doing it right!  It turns out that two different variants of
> “gzip” appear: one in ‘%final-inputs’ (the implicit inputs of
> ‘gnu-build-system’) and another one somewhere else, hence the collision.
>
> The solution is to pass ‘--allow-collisions’, which is what ‘guix
> environment’ does by default precisely for that reason (see commit
> afd06f605bf88a796acefc7ed598b43879346a6b).

Nice!
I would be able to find myself! ;-)

However, in the commit afd06f605bf88a796acefc7ed598b43879346a6b, the
behaviour appears to me inconsistent. On one hand, the default is #f
in guix/profiles.scm or in guix/scripts/package.scm, on the other hand
the default is #t in guix/scripts/environment.scm. Does a rationale
exist for that?

Why not turn on #t all the defaults and instead have the option
"--no-allow-collisions". Keeping the option "--allow-collisions" for
compatibility.


> We could check exactly why we end up with several ‘gzip’ instances, but
> overall I think this kind of thing is hard to avoid for package inputs.

Yes, we could investigate from where comes this collisions.


Thank you for the explanations and the pointers.


All the best,
simon