#10905: Incorrect number of parameters in "role" errors -------------------------------------+------------------------------------- Reporter: crockeea | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Resolution: | Keywords: roles Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect | Unknown/Multiple warning at compile-time | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by goldfire): Here's my test case. It produces the bad output in 7.10, but (as noted above) not in HEAD. {{{ {-# LANGUAGE PolyKinds #-} module T10905 where import Data.Coerce import Data.Functor.Identity data TaggedT s m b = TagT { untagT :: m b } foo :: TaggedT () [] Int -> TaggedT () [] (Identity Int) foo = coerce -- test the printing of TaggedT's role signature }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10905#comment:2 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler