Identity operators (=== and !==) in Swift - Mini Project: Build & Apply

Identity Operators (=== and !==) in Swift

📖 Scenario: Imagine you are managing a list of pets in a pet shelter. Each pet is represented by an object. Sometimes, you want to check if two variables point to the exact same pet object, not just pets that look alike.

🎯 Goal: You will create two pet objects, then use Swift's identity operators === and !== to check if two variables refer to the same object.

📋 What You'll Learn

Create two instances of a class called Pet with a name property

Create two variables referencing these instances

Use the identity operator === to check if two variables refer to the same object

Use the identity operator !== to check if two variables do not refer to the same object

Print the results of these identity checks

💡 Why This Matters

🌍 Real World

In real apps, identity operators help check if two variables point to the same object in memory, which is important when managing shared resources or references.

💼 Career

Understanding identity operators is useful for Swift developers working on iOS apps, especially when handling object references, memory management, and debugging.

1

Create two Pet objects

Create a class called Pet with a property name of type String. Then create two instances called pet1 with name "Buddy" and pet2 with name "Buddy".

Swift

class Pet {
    var name: String
    init(name: String) {
        self.name = name
    }
}

// Create pet1 and pet2 instances below
# Your code here

Need a hint?

Define the class with a name property and an initializer. Then create two separate instances with the same name.

2

Create a third variable referencing pet1

Create a variable called pet3 and assign it to reference the same object as pet1.

Swift

class Pet {
    var name: String
    init(name: String) {
        self.name = name
    }
}

let pet1 = Pet(name: "Buddy")
let pet2 = Pet(name: "Buddy")

// Create pet3 referencing pet1 below
# Your code here

Need a hint?

Assign pet3 to pet1 so both point to the same object.

3

Use identity operators to compare pets

Use if statements with the identity operator === to check if pet1 and pet3 refer to the same object, and if pet1 and pet2 refer to the same object. Store the results in variables samePet1and3 and samePet1and2 respectively.

Swift

class Pet {
    var name: String
    init(name: String) {
        self.name = name
    }
}

let pet1 = Pet(name: "Buddy")
let pet2 = Pet(name: "Buddy")
let pet3 = pet1

// Use identity operators to compare pet1 and pet3, pet1 and pet2
# Your code here

Need a hint?

Use === to check if two variables point to the same object and assign the result to variables.

4

Print the results of identity checks

Print the values of samePet1and3 and samePet1and2 using print statements.

Swift

class Pet {
    var name: String
    init(name: String) {
        self.name = name
    }
}

let pet1 = Pet(name: "Buddy")
let pet2 = Pet(name: "Buddy")
let pet3 = pet1

let samePet1and3 = (pet1 === pet3)
let samePet1and2 = (pet1 === pet2)

// Print the results below
# Your code here

Need a hint?

Use print to show the boolean results of the identity checks.