Subject: Re: [bug#77708] [PATCH] gexp: ‘with-parameters‘ is respected by caches.

From: Ludovic Courtès <[email-masked]>
Date: Thu, 26 Jun 2025 08:56:51 +0200

Hello,

Quick note…

David Elsing <[email-masked]> writes:

> Ludovic Courtès <[email-masked]> writes:

[...]

>> Overall I have two main concerns: the added complexity and the run-time
>> overhead.  I would be tempted to just not pretend supporting
>> <parameterized> for arbitrary parameters than to pay this price.
>>
>> WDYT?
>
> I think parameterized packages would be very useful. Something like the
> previous approach [1] would of course be nicer, but I didn't find any
> information why it was not continued.

Oh, I see.  The GSoC project you’re referring to was very nice but IMO
went a bit too far in terms of what it provides; but the main factor for
it being discontinued is that the intern walked away after the
internship I believe, and nobody picked it up.  FWIW, I was advocating
for something simpler and that would try to reduce the risks of
combinatorial explosion¹.

At any rate, I don’t think parameters (in the sense of SRFI-39) can be a
useful building block for parameterized packages (in the sense of Gentoo
USE flags.)  I think parameterized packages need to be implemented with
some declarative interface as was proposed during that GSoC project and
that earlier message I mentioned.

I hope that makes sense!

Thanks,
Ludo’.

¹ https://lists.gnu.org/archive/html/guix-devel/2020-11/msg00312.html