It's probably because other importers are structured that way. I'd be in favor of changing that and using the condition system.

Le 27 septembre 2022 13:33:56 GMT+02:00, Csepp <raingloom@riseup.net> a écrit :
>The specific error is this:
>Wrong number of values returned to continuation (expected 2)
>It is caused by opam->guix-package silencing intermediate errors by
>using and-let* (the poor person's Maybe monad) and returning #f when the
>receiving side expects two return values.
>
>Initial reproducer:
>guix import opam -r mirage
>
>Also happens with opam-monorepo.
>
>Cc-ing Julien whom might know why the code is structured this way?  It's
>not like the calling side can handle a falsy return and the error is not
>detected early either, so the user doesn't even know what is causing it.
>Can I just turn it all into errors?  Or maybe we can use the condition
>system?
>