#13734: Code requires ScopedTypeVariables, possibly erroneously -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by RyanGlScott): This looks like expected behavior to me. After all, this won't typecheck without `ScopedTypeVariables` either: {{{#!hs {-# Language ScopedTypeVariables, TypeApplications, InstanceSigs #-} import Data.Proxy class Sized f where size :: proxy f -> Int instance Sized Int where size :: proxy Int -> Int size _ = 42 instance (Sized a, Sized b) => Sized (a, b) where size :: proxy (a, b) -> Int size _ = size (Proxy :: Proxy a) + size (Proxy :: Proxy b) }}} I don't see why `TypeApplications` would be different in that regard. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13734#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler