#12515: Pattern synonyms with non-conid/consym names give poor error messages -------------------------------------+------------------------------------- Reporter: pkmx | Owner: Type: feature | Status: new request | Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Incorrect Unknown/Multiple | warning at compile-time Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- The following: {{{#!hs {-# LANGUAGE PatternSynonyms #-} -- Correct: pattern P = () pattern p = () }}} gives a rather unhelpful error message: {{{ parse error on input ‘=’ Perhaps you need a 'let' in a 'do' block? e.g. 'let x = 5' instead of 'x = 5' }}} Ideally, it should hint that the name of pattern should follow constructor identifier rules. ---- In the same vein, the following: {{{#!hs {-# LANGUAGE PatternSynonyms #-} -- Correct: pattern (:+) = () pattern (+) = () }}} currently gives: {{{ error: parse error on input ‘+’ }}} It should hint that the operator should begin with a {{{:}}}. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12515 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler