#12165: Multiple pattern type signatures accepted -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple PatternSynonyms | Architecture: | Type of failure: GHC accepts Unknown/Multiple | invalid program Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- This hogwash is accepted: {{{ pattern P :: a -> b -> Maybe (a,b) pattern P :: foo => bar => blah -> urgh pattern P x y = Just (x, y) }}} A little experimentation shows that only the first pattern signature is examined. Others are accepted and ignored. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12165 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler