#15359: Quantified constraints do not work with equality constraints -------------------------------------+------------------------------------- Reporter: goldfire | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: 8.6.1 Component: Compiler | Version: 8.5 Resolution: | Keywords: | QuantifiedConstraints Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by goldfire): All the examples in comment:7 involve superclass constraints, mostly on classes without any methods. This is interesting for type-level programming, but it's not clear where (even in type-level programming) the rubber is hitting the road here. Can you give a concrete example of a function that usefully uses an equality constraint in the head of an implication? This should be a function that I can call (that is, the constraints are satisfiable). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15359#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler