protocol Equatable Instances of conforming types can be compared for value equality using operators == and !=. When adopting Equatable, only the == operator is required to be implemented. The standard library provides an implementation for !=. Inheritance View Protocol Hierarchy → Import import Swift Instance Methods func ==(_:rhs:) Required Return true if lhs is equal to rhs. Equality implies substitutability. When x == y, x and y are interchangeable in any code that only depends on their values. Class instance identity as distinguished by triple-equals === is notably not part of an instance's value. Exposing other non-value aspects of Equatable types is discouraged, and any that are exposed should be explicitly pointed out in documentation. Equality is an equivalence relation x == x is true x == y implies y == x x == y and y == z implies x == z Inequality is the inverse of equality, i.e. !(x == y) iff x != y. Declaration func ==(lhs: Self, rhs: Self) -> Bool