#11333: GHCi does not discharge satisfied constraints ----------------------------------------+-------------------------- Reporter: Iceland_jack | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.1 Keywords: | Operating System: Linux Architecture: Unknown/Multiple | Type of failure: Other Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: ----------------------------------------+-------------------------- Don't know if this is the intended behaviour (GHCi, version 8.1.20151231), with the new extension TypeApplications. For the function [https://hackage.haskell.org/package/base-4.8.1.0/docs /Text-Show.html#v:show show]: {{{#!hs Prelude> :set -XTypeApplications Prelude> :t show show :: Show a => a -> String Prelude> :t show @Int show @Int :: Show Int => Int -> String }}} And the function [https://hackage.haskell.org/package/base/docs/Data- Typeable.html#v:eqT eqT] (`:: forall a b. (Typeable a, Typeable b) => Maybe (a :~: b)`): {{{#!hs Prelude> :set -XTypeApplications Prelude> import Data.Typeable Prelude Data.Typeable> :t eqT eqT :: forall k1 (a :: k1) (b :: k1). (Typeable a, Typeable b) => Maybe (a :~: b) Prelude Data.Typeable> :t eqT eqT :: forall k1 (a :: k1) (b :: k1). (Typeable a, Typeable b) => Maybe (a :~: b) Prelude Data.Typeable> :t eqT @Int eqT @Int :: (Typeable Int, Typeable b) => Maybe (Int :~: b) }}} Should the types of `show @Int` and `eqT @Int` not be `Int -> String` and `(Typeable b) => Maybe (Int :~: b)` respectively? -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11333 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler