Num – Numeric Types
Numclass supports basic numeric methods for its types:
(+), (-), (*) :: a -> a -> a
negate, abs, signum :: a -> a
Notice that division is not included here because of how it is handled differently for integers floating-point numbers, as we will see in the next two classes (
signummethod returns the sign of a number (-1 for negative numbers and 1 for positive ones).