Swift 4 Protocol-Oriented Programming - Third Edition

Conforming to the Equatable protocol

In this section, we will show how we can conform to the Equatable protocol using extensions. When a type conforms to the Equatable protocol, we can use the equal-to (==) operator to compare for equality and the not-equal-to (!=) operator to compare for inequality.

If you will be comparing instances of a custom type, it is a good idea to have that type conform to the Equatable protocol because it makes comparing instances very easy.

Let's start off by creating the type that we will compare. We will name this type Place:

struct Place { 
  let id: String 
  let latitude: Double 
  let longitude: Double 
} 

In the Place type, we have three properties that represent the ID of the place and the latitude and longitude ...