hi i seem to have stumbled upon a bug which somehow seems to be realted to the module system and functional dependencies. attached are four files (sorry about that, but it seems to happen when the class and instance are in different modules), 2 files per example. when Bug1 is loaded, no error is reported (although it should have been). if i edit the file (say just add a blank line) using the :e feature, then an error is reported, but seems like the wrong error - it says ERROR "Bug1.hs":6 - Illegal type in class constraint while if i just move the class to the same module, i get the correct error ERROR "Bug1.hs":8 - Undefined type variable "t'" (GHC comes up with this same error) when Bug2 is loaded i get the error: INTERNAL ERROR: inheritFundeps - predicate failed to match it's own head! although these messages dont seem related it seems like their cause is common. i am using the vesrion of hugs from the CVS from about 2 weeks ago (doesnt seem to have a number it just says YYMMDD) bye iavor