20 Feb
2009
20 Feb
'09
7:11 a.m.
you are applying the type to lookup only!
try let lookupIn = ((flip lookup ) :: (Eq a) => [(a, b)] -> a -> Maybe b )
On Fri, Feb 20, 2009 at 07:27, Matt R
So what's this all about then? How come a has become ()?
ghci> :t lookup lookup :: (Eq a) => a -> [(a, b)] -> Maybe b ghci> :t flip lookup flip lookup :: (Eq a) => [(a, b)] -> a -> Maybe b ghci> let lookupIn = (flip lookup :: (Eq a) => [(a, b)] -> a -> Maybe b ) ghci> :t lookupIn lookupIn :: [((), b)] -> () -> Maybe b _______________________________________________ Beginners mailing list Beginners@haskell.org http://www.haskell.org/mailman/listinfo/beginners
-- Rafael Gustavo da Cunha Pereira Pinto Electronic Engineer, MSc.