#10846: PartialTypeSignatures change implicit CallStack behavior -------------------------------------+------------------------------------- Reporter: | Owner: nitromaster101 | Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.10.2 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Revisions: | -------------------------------------+------------------------------------- I have two functions, f and f2 which are identical expect for the use of PartialTypeSignatures in f2. GHC produces a warning and says that f2's wildcard is filled in by String, which is correct. {{{#!hs {-# LANGUAGE ImplicitParams, PartialTypeSignatures #-} import GHC.Types f :: (?loc :: CallStack) => String f = show $ map (srcLocStartLine . snd) $ getCallStack ?loc f2 :: (?loc :: CallStack) => _ f2 = show $ map (srcLocStartLine . snd) $ getCallStack ?loc f_caller = f f2_caller = f2 }}} {{{ [1 of 1] Compiling Main ( Bug2.hs, interpreted ) Bug2.hs:8:30: warning: Found type wildcard ‘_’ standing for ‘String’ In the type signature for: f2 :: (?loc :: CallStack) => _ Ok, modules loaded: Main. *Main> f_caller "[6,11]" *Main> f2_caller "[9]" }}} f2_caller should have two entries (f2_caller's line and f2's line), just like f_caller. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10846 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler