Derivation is missing output

[Hartmut Goebel]

Hi,

I'm still working on the download and importer for hex.pm and the rebar3
build-system for Erlang. So far I made good progress, but now I stepped
over a curious issue:

The downloader is modeled like the one for git, bzr and hg, creating a
fixed script controlled by environment variables. The script is created
as expected. But the script is never run. After some debugging, I
discovered that the source package's .drv file does not define any output:

    Derivce([],[…inputs…])

What can be the reason for this?

Some background (the whole source can be found at
https://gitlab.digitalcourage.de/htgoebel/guix/-/tree/HG-rebar-build-system):

    (source
     (origin
       (method hexpm-fetch)
       (uri "https://repo.hex.pm/tarballs/getopt-1.0.1.tar";)
       (sha256
        (base32 "1fhqnn4dvcil12cmqmzkmlk14lq5rn7ingld2380i6nl8v2dvm48"))))

and hexpm-fetch returns

  (mlet %store-monad ((guile (package->derivation guile system)))
    (gexp->derivation (pk (or name file-name)) build
                       … more arguments))

-- 
Regards
Hartmut Goebel

| Hartmut Goebel          | h.goebel@crazy-compilers.com               |
| www.crazy-compilers.com | compilers which you thought are impossible |