Harendra Kumar <harendra.ku...@gmail.com> writes: > I see the following errors when compiling with ghc head version: > > $ ghc-stage2 --version > The Glorious Glasgow Haskell Compilation System, version 9.3.20210608 > > $ cabal build --with-compiler ghc-stage2 --allow-newer > > Data/Colour/CIE.hs:80:12: error: > Ambiguous occurrence ‘sum’ > It could refer to > either ‘Prelude.sum’, > imported from ‘Prelude’ at Data/Colour/CIE.hs:25:8-22 > (and originally defined in ‘Data.Foldable’) > or ‘Data.List.sum’, > imported from ‘Data.List’ at Data/Colour/CIE.hs:41:1-16 > (and originally defined in ‘GHC.List’) > | > 80 | total = sum $ map fst l > | ^^^ > > Can someone briefly describe this change and what's the recommended way of > fixing this? Just hide the Data.List definition? I do not see this > mentioned in the release notes of 9.2/9.4 here: > https://ghc.gitlab.haskell.org/ghc/doc/users_guide/9.2.1-notes.html > Indeed, this is due to the monomorphic Data.List proposal, which the CLC decided would accompany the addition of Data.List.singleton. The correct fix here is to either qualify the import of `Data.List` or add an explicit import list. I'll try to remember to add a note about this to the release notes and migration guide.
Cheers, - Ben
signature.asc
Description: PGP signature
_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
