#8095: TypeFamilies painfully slow -------------------------------------------------+------------------------- Reporter: MikeIzbicki | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler (Type checker) | Version: 7.6.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time performance bug | Unknown/Multiple Test Case: | Difficulty: Blocking: | Unknown | Blocked By: | Related Tickets: 5321 -------------------------------------------------+------------------------- Comment (by goldfire): I've been playing around with type families recently, so I just took a look at this one. I can reproduce Mike's observed behavior exactly, both with 7.6.3 and with HEAD (although I had to strike the "`import GHC.TypeLits`" to get the produced file to compile with HEAD). It seems that the problem lies outside the area I've been editing, so I'm going to leave this for now. For what it's worth, I tried this example with closed type families, and the resultant behavior is the same. This leads me to believe the problem is indeed in the constraint solver. Thanks for reporting and for creating a great test environment! -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8095#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler