The attoparsec package on hackage defines multiple internal libraries inside
one package, named "attoparsec" and "attoparsec-internal", with the first
depending on the latter. Importing attoparsec using `guix import hackage
attoparsec` therefore yields the following erroneous package definition:
(define-public ghc-attoparsec
(package
(name "ghc-attoparsec")
(version "0.14.4")
(source
(origin
(method url-fetch)
(uri (hackage-uri "attoparsec" version))
(sha256
(base32 "0v4yjz4qi8bwhbyavqxlhsfb1iv07v10gxi64khmsmi4hvjpycrz"))))
(build-system haskell-build-system)
(inputs (list ghc-scientific ghc-attoparsec-internal))
(native-inputs
(list ghc-quickcheck
ghc-quickcheck-unicode
ghc-tasty
ghc-tasty-quickcheck
ghc-vector))
(arguments
`(#:cabal-revision
("1" "149ihklmwnl13mmixq6iq5gzggkgqwsqrjlg2fshqwwbvbd4nn3r")))
(home-page "https://github.com/bgamari/attoparsec";)
(synopsis "Fast combinator parsing for bytestrings and text")
(description
"This package provides a fast parser combinator library, aimed
particularly at
dealing efficiently with network protocols and complicated text/binary file
formats.")
(license license:bsd-3)))
Note that `ghc-attoparsec-internal` is listed as a dependency of
`ghc-attoparsec`. I believe that is incorrect, and that we should filter out
the internal dependencies from `inputs`, just like we filter out
`ghc-attoparsec` from the list of `native-inputs`.
