#15166: Bad error message when `!` is used without BangPatterns extension -------------------------------------+------------------------------------- Reporter: sighingnow | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: Incorrect Unknown/Multiple | error/warning at compile-time Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- For {{{#!hs f :: a -> a f !x = x }}} ghc-HEAD gives {{{ P.hs:22:1: error: The type signature for ‘f’ lacks an accompanying binding | 22 | f :: a -> a | ^ }}} Here ghc should suggest `BangPatterns` extension. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15166 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler