
#8084: Enabling PolyKinds makes some type errors weird --------------------------------------------+------------------------------ Reporter: MartijnVanSteenbergen | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type checker) | Version: 7.6.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Test Case: | Difficulty: Unknown Blocking: | Blocked By: | Related Tickets: --------------------------------------------+------------------------------ Comment (by simonpj): I'd be interested to know what people think. * Should GHC display kind arguments by default (as now) or only with an explicit flag? One dificulty with the latter is that an explicit flag is not very discoverable. And if kind arguments are not displayed by default you might get messages like `Cannot unify X with X`, which looks like a bug, whereas `Cannot unify (X *) with (X (*->*))` makes more sense. * Should there be syntax to distinguish kind arguments? e.g. `(Any {*} Y)`, or `(Any @* Y)`. There are no major issues of principle here, just ones of design. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8084#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler