#11974: `default` declaration doesn't allow higher-kinded types -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: patch Priority: normal | Milestone: Component: Compiler | Version: 8.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D2136 Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): You're proposing a wholesale extension of the defaulting mechanism. Defaulting happens as per the Haskell Report or with a [https://downloads.haskell.org/~ghc/8.0.1-rc4/docs/html/users_guide/ghci.html #type-defaulting-in-ghci small extension]. In either case, the set of defaultable classes is fixed. You're proposing changing this, which is quite different than the purpose of this ticket. (This ticket is about letting `default` declarations include types that are already defaultable.) If you want this new behavior, I encourage you to write a specification of it (on a wiki page) and then submit a feature request. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11974#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler