Something is rotten in the state of dynamic types and multiparameter type classes. I'd be grateful if you'd fix it soon, this is causing me big difficulties.
I'm sorry if this is complicated, but I've already spent two hours narrowing this bug down and the security are about to throw me out of the building . . . > uname -a SunOS bob 5.8 Generic_108528-12 sun4u sparc SUNW,Sun-Fire-280R > ghc --version The Glorious Glasgow Haskell Compilation System, version 5.02.2 > mkdir bug > cd bug > tar -xvzf [attachment] > ghc -fglasgow-exts -fallow-overlapping-instances -fallow-undecidable-instances >-package lang FoldersTest.hs TestFT.hs -o testFT > ./testFT Fail: <<loop>> [ OK, so main function isn't working] > ghci -fglasgow-exts -fallow-overlapping-instances -fallow-undecidable-instances >-package lang [GHCi startup screen] Prelude> :load FoldersTest Compiling FoldersTest ( FoldersTest.hs, interpreted ) Ok, modules loaded: FoldersTest. FoldersTest> Prelude.putStrLn (Prelude.show (Dynamic.typeOf (Prelude.undefined :: Folder))) Folders.Folder [So this DOES terminate. However it is exactly the same as the main function called by testFT. So what is going on????]
bug.tar.gz
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