#16146: Trivial partial type signature kills type inference in the presence of GADTs -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.6.3 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 simonpj): Well I suppose we could have a different typing rule for the case where there is no quantification. I'm not very keen on this, because it changes behaviour in a subtle way, and just adding an unrelated quantifier to the partial signature would completely change its typing rule. It's user-facing, so perhaps GHC-proposal-worthy? The relevant function is `tcExprSig`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/16146#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler