10 Oct
2011
10 Oct
'11
9:26 a.m.
Am 08.10.2011 01:40, schrieb Joe Van Dyk:
I'm going through the 99 Haskell problems and am trying to write quickCheck properties for each one.
-- 3 (find k"th element of a list) element_at xs x = xs !! x prop_3a xs x = (x< length xs&& x>= 0) ==> element_at xs (x::Int) == (xs !! x::Int)
The definition and test look very similar (basically "=" is replaced by "=="). So this seems to test reliability of definitions and Eq instances. Such tests should not be necessary. (Testing different implementations for equality makes more sense.) Cheers Christian