10 Jun
2011
10 Jun
'11
7:10 p.m.
On Fri, Jun 10, 2011 at 12:05 PM, Alexander Solla
On Thu, Jun 9, 2011 at 6:04 PM, Felipe Almeida Lessa < felipe.lessa@gmail.com> wrote:
Something like this?
equivalenceClosure = fix $ \f e -> let e' = reflexivity . symmetry . transitivity $ e in if e' == e then e else f e'
Cheers,
-- Felipe.
I managed something even "clearer". I still have very little intuition about what's going on, but I had an aha moment -- which I promptly forgot :0( -- and at least there's a mechanical translation from the iterate version to the fix one.
equivalenceClosure :: (Ord a) => Relation a -> Relation a equivalenceClosure = fix (\f -> reflexivity . symmetry . transitivity)
Cancel that, it's not passing my tests.