bug#36653: [PATCH v2] guix import stackage: default to a LTS release compatible with GHC 8.4

[Timothy Sample]

Hello,

Over a year later, and I finally went ahead and pushed this!  See commit
f0bb2662bb05625042094e124521197c5f43505e.

Ludovic Courtès <ludo@gnu.org> writes:

> Robert Vollmert <rob@vllmrt.net> skribis:
>
>> +;;; Latest LTS version compatible with bundled ghc version.
>> +(define %default-lts-version "12.26")
>
> What about storing this elsewhere?  Perhaps in the ‘properties’ field of
> the ‘ghc’ package?  That should make it easier to keep these numbers in
> sync.

That’s true, but we already have this problem with the Hackage importer.
It has a version-specific list of packages included with GHC.  It’s true
that two wrongs don’t make a right, but having this patch in place –
even with shortcomings – will prevent real problems.  Besides, we can
always fix it later.

> Besides, it’s usually clearer to separate unrelated cleanups, but it’s
> no big deal in this case.

Agreed.  (The typos were fixed in the interim, but I let the “https”
change hitch a ride along with the LTS version stuff.)

Anyway, this will pave the way for a lint check and then we can finally
put an end to the Haskell package roll-backs.  :)


-- Tim