#9173: Better type error messages -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by rwbarton): The error there would not be about the type of `foo`, though. It would be about the type of `"Howdy!"`. {{{ Foo.hs:4:7: Couldn't match expected type ‘Int’ with actual type ‘[Char]’ In the expression: "Howdy!" In an equation for ‘foo’: foo = "Howdy!" }}} The "actual type" is ... the actual type of the expression `"Howdy!"` that the compiler points out. The "expected type" is the type expected from the context, that is, the type the expression would have to have for the whole thing to type check. I know lots of people find this confusing but I have never been able to understand why... -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9173#comment:10 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler