#15474: Error message mentions Any -------------------------------------+------------------------------------- Reporter: monoidal | Owner: (none) Type: bug | Status: new Priority: low | Milestone: 8.8.1 Component: Compiler | Version: 8.4.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Poor/confusing | Unknown/Multiple error message | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Description changed by monoidal: Old description:
I'm not sure if this is a bug. File:
{{{#!hs {-# LANGUAGE RankNTypes #-} {-# LANGUAGE TypeInType #-} module T15474 where
import Data.Kind (Type)
data Proxy a
type Forall = forall t. Proxy t
f1 :: forall (t :: Type). Proxy t f1 = f1
f2 :: Forall f2 = f1 }}}
gives an error message mentioning Any:
{{{ • Couldn't match type ‘GHC.Types.Any’ with ‘*’ Expected type: Proxy t Actual type: Proxy t0 }}}
The appearance of Any is suspicious - I thought it's an implementation detail?
New description: I'm not sure if this is a bug. File: {{{#!hs {-# LANGUAGE RankNTypes #-} {-# LANGUAGE TypeInType #-} module T15474 where import Data.Kind (Type) data Proxy a type Forall = forall t. Proxy t f1 :: forall (t :: Type). Proxy t f1 = f1 f2 :: Forall f2 = f1 }}} gives an error message mentioning Any: {{{ • Couldn't match type ‘GHC.Types.Any’ with ‘*’ Expected type: Proxy t Actual type: Proxy t0 }}} The appearance of Any is suspicious to me - I thought it's an implementation detail? -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15474#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler