michael rice
cf2 :: Rational -> [Int] cf2 a = let ai = floor a <-- Doesn't this make ai an Int? -Michael in if a == (toRational ai) then [ai] else ai : cf2 (1 / (a - ai))
One thing that you could try, is ghci in addition to (or instead of) Hugs. That will give you another take on the error messages, where Hugs says:
Main> :load cf.hs ERROR "cf.hs":7 - Type error in application *** Expression : ai : cf2 (1 / (a - ai)) *** Term : ai *** Type : Ratio Integer *** Does not match : Int
ghci will tell you: Couldn't match expected type `Rational' against inferred type `Int' In the second argument of `(-)', namely `ai' In the second argument of `(/)', namely `(a - ai)' In the first argument of `cf2', namely `(1 / (a - ai))' So while this is (almost) right:
cf2 a = let ai = floor a <-- Doesn't this make ai an Int? -Michael
The problem is the subtraction of ai from a, which forces them to be the same type. I tend to find ghc's messages more informative than Hugs's (but perhaps it is just that I am more familiar with ghc?). -k -- If I haven't seen further, it is by standing in the footprints of giants