Returns true if x and y are equivalent, false otherwise.
Returns true if x and y are equivalent, false otherwise.
Returns false if x and y are equivalent, true otherwise.
Returns false if x and y are equivalent, true otherwise.
Constructs a new Eq instance for type B where 2 elements are
equivalent iff eqv(f(x), f(y)).
Constructs a new Eq instance for type B where 2 elements are
equivalent iff eqv(f(x), f(y)).