16 Apr
2008
16 Apr
'08
7 p.m.
I'm still confused about this point:
On 4/16/08, Dan Weston
class C a b c | c -> a b
Notice that there are multiple (two) parameters in the range of the FD.
It's tempting to convert the above to
class C a b c | c -> a, c -> b
but this yields a weaker (in terms of type improvement) system.
In both cases the statement is that given a type x, the instance C x y z for some y,z and the constraint C x a b, we unambiguously have a ~ y, b ~ z (where ~ is type equality) How does the order in (c -> a b) matter? -- ryan