#8678: Deriving `Functor` complains about existential type -------------------------------------------------+------------------------- Reporter: heisenbug | Owner: Type: bug | Status: Priority: normal | closed Component: Compiler | Milestone: Resolution: fixed | Version: 7.7 Operating System: Unknown/Multiple | Keywords: Type of failure: None/Unknown | Architecture: Test Case: | Unknown/Multiple deriving/should_compile/T8678 | Difficulty: Blocking: | Unknown | Blocked By: | Related Tickets: -------------------------------------------------+------------------------- Changes (by simonpj): * status: new => closed * testcase: => deriving/should_compile/T8678 * resolution: => fixed Comment: Good idea. I have liberalise what `deriving Functor` will do, so that it looks only at the way in which the last type parameter is used. This makes perfect sense. Let's not merge this; it's a new feature. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8678#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler