#8631: Need ImpredicativeTypes for GeneralizedNewtypeDeriving? -------------------------------------+------------------------------------ Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.7 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 simonpj): `-XImpredicativeTypes` it not a very well-defined flag. It might make this program compile, and I think it'd be safe to enable it for GND- produced code. But it has had no love for many years. Do give it a try; which would make Q2 moot. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8631#comment:6 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler