Curiously enough, this is a new bug. The patch that fixed my previous problem does not solve this issue.
I had a problem with derived Eq and Ord with a polymorphic representation of regular expressions. Simon Peyton-Jones recently put a updated ghc/compiler/typecheck/TcGenDeriv.lhs in CVS, FYI. best, leon On Thursday 23 January 2003 11:01, Malcolm Wallace wrote: > The interactive loop of ghci displays an interesting evaluation fault > to do with derived equality. In the attached source file, there is > a simple guard which tests some equalities, and basically the same > value is given on the left and right of the (==). Yet, it evaluates > to False in interactive mode, whereas it (correctly) evaluates to True > when compiled. > > > $ ghci > ___ ___ _ > / _ \ /\ /\/ __(_) > / /_\// /_/ / / | | GHC Interactive, version 5.04.2, for Haskell 98. > / /_\\/ __ / /___| | http://www.haskell.org/ghc/ > \____/\/ /_/\____/|_| Type :? for help. > > Loading package base ... linking ... done. > Loading package haskell98 ... linking ... done. > Prelude> :l Small > Compiling Main ( Small.hs, interpreted ) > Ok, modules loaded: Main. > *Main> main > "*** Exception: Four.bceFour: precondition fails:arrows not parallel > f = E > g = E > > > $ ghc -o Small Small.hs > $ ./Small > "it works" > > > I have verified that the fault exists at least as far back as 5.02.3. > > Regards, > Malcolm _______________________________________________ Glasgow-haskell-bugs mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
