[Haskell-cafe] Generalized Newtype Deriving not allowed in Safe Haskell
Omari Norman
omari at smileystation.com
Thu Apr 9 01:43:34 UTC 2015
When compiling code with Generalized Newtype Deriving and the -fwarn-unsafe
flag, I get
-XGeneralizedNewtypeDeriving is not allowed in Safe Haskell
This happens both in GHC 7.8 and GHC 7.10.
I thought I remembered reading somewhere that GNTD is now part of the safe
language? The GHC manual used to state that GNTD is not allowed in Safe
Haskell:
https://downloads.haskell.org/~ghc/7.6.3/docs/html/users_guide/safe-haskell.html#safe-language
But this language on GNTD not being part of the safe language was removed
in the 7.8 manual:
https://downloads.haskell.org/~ghc/7.8.2/docs/html/users_guide/safe-haskell.html#safe-language
The GHC release notes don't say anything about this one way or the other.
Thoughts?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.haskell.org/pipermail/haskell-cafe/attachments/20150408/85364b03/attachment.html>
More information about the Haskell-Cafe
mailing list