Example
All basic datatypes (like Int, String, Eq a => [a]) from Prelude except for functions and IO have instances of Eq. If a type instantiates Eq it means that we know how to compare two values for value or structural equality.
> 3 == 2
False
> 3 == 3
True
Required methods
(==) :: Eq a => a -> a -> Booleanor(/=) :: Eq a => a -> a -> Boolean(if only one is implemented, the other defaults to the negation of the defined one)
Defines
(==) :: Eq a => a -> a -> Boolean(/=) :: Eq a => a -> a -> Boolean
Direct superclasses
None
