#10351: Inferred type is rejected -------------------------------------+------------------------------------- Reporter: simonpj | Owner: Type: bug | Status: closed Priority: normal | Milestone: Component: Compiler | Version: 7.10.1 Resolution: fixed | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: None/Unknown | Unknown/Multiple Blocked By: | Test Case: Related Tickets: | typecheck/should_fail/T10351 | Blocking: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by simonpj): The difficulty before is that GHC would infer a type ''and then complain that its own inferred type was illegal''. That seems confusing. Moreover sometimes, if it had simply refrained from generalising over that constraint, the program would have been accepted. So the change means that strictly more programs are accepted. But as you discovered, failing to generalise over a constraint may mean that it is reported as unsolved; and only when you fix that does it ask for `FlexibleContexts`. I'm open to suggestions, but the new behaviour seems cleaner to me. Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10351#comment:4 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler