GNU bug report logs - #58112
OPAM importer fails in lookup-node

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From: Csepp <raingloom@HIDDEN>
To: Bug reports for GNU Guix <bug-guix@HIDDEN>
Subject: OPAM importer fails in lookup-node
Date: Tue, 27 Sep 2022 13:33:56 +0200
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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?