[Haskell-cafe] [] == []

Hi all, GHC is not happy with this: f = [] == [] nor this: f' = ([]::(Eq a) => [a]) == ([]::(Eq a) => [a]) but this is OK: f'' = ([]::[Integer]) == ([]::[Integer]) GHCI is comfortable with [] == [], so why not GHC? 'Just curious. Cheers, Paul