[GHC] #14661: Cannot derive (newtype I a b = I (F a -> F b) deriving newtype Category) for type family F
GHC
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Thu Jan 11 17:43:54 UTC 2018
#14661: Cannot derive (newtype I a b = I (F a -> F b) deriving newtype Category)
for type family F
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Reporter: Iceland_jack | Owner: (none)
Type: bug | Status: new
Priority: normal | Milestone:
Component: Compiler | Version: 8.4.1-alpha1
Resolution: | Keywords:
| DerivingStrategies, deriving,
| TypeFamilies
Operating System: Unknown/Multiple | Architecture:
| Unknown/Multiple
Type of failure: None/Unknown | Test Case:
Blocked By: | Blocking:
Related Tickets: | Differential Rev(s):
Wiki Page: |
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Comment (by simonpj):
Interesting. The type family is a red herring. Same thing happens with
`data Interp a = I`.
--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14661#comment:1>
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