#1965: Allow unconstrained existential contexts in newtypes -------------------------------------+------------------------------------ Reporter: guest | Owner: Type: feature request | Status: new Priority: normal | Milestone: 7.6.2 Component: Compiler | Version: 6.8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Comment (by heisenbug): Replying to [comment:13 pumpkin]:

To be clear about what I'm looking for:

Yes, I always wondered how existentially quantifying over a type constructor with non-* domain kinds can ever necessitate extra information at runtime. I fully support the reopen proposal because of `data Hidden :: k -> * where Hide :: t a -> Hidden t` wants to be a `newtype`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/1965#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler