[Haskell-cafe] monomorphism restriction

[Rex Page]

Definition of f:
    f = foldr (+) 0
Types:
    0 :: (Num t) => t
    foldr (+) 0 :: Num a => [a] -> a
    f :: [Integer] -> Integer

Please remind me, again, of the advantages of f being something different from 
the formula defining it.

  - Rex Page