Generic type declaration in Swift - Mini Project: Build & Apply

Generic type declaration

📖 Scenario: Imagine you want to create a simple container that can hold any type of item, like a box that can store toys, books, or clothes. Instead of making a new box for each item type, you can make one box that works for all types using generics.

🎯 Goal: You will build a generic Box struct in Swift that can hold any type of item. You will then create boxes for different item types and print their contents.

📋 What You'll Learn

Create a generic struct called Box with a type parameter Item

Add a property item of type Item to Box

Create a variable toyBox of type Box holding a String value

Create a variable numberBox of type Box holding an Int value

Print the contents of both boxes

💡 Why This Matters

🌍 Real World

Generics let you write flexible and reusable code that works with any data type, like containers, collections, or algorithms.

💼 Career

Understanding generics is important for Swift developers to create clean, efficient, and type-safe code used in apps and frameworks.

1

Create a generic struct called Box

Write a generic struct called Box with a type parameter Item. Inside it, declare a property called item of type Item.

Swift

struct Box {
    // Your code here
}

Need a hint?

Use struct Box to declare a generic struct. Inside, add var item: Item.

2

Create a Box holding a String

Create a variable called toyBox of type Box holding the string "Teddy Bear".

Swift

struct Box {
    var item: Item
}

// Your code here

Need a hint?

Use var toyBox = Box(item: "Teddy Bear") to create the box.

3

Create a Box holding an Int

Create a variable called numberBox of type Box holding the integer 42.

Swift

struct Box {
    var item: Item
}

var toyBox = Box(item: "Teddy Bear")

// Your code here

Need a hint?

Use var numberBox = Box(item: 42) to create the box.

4

Print the contents of both boxes

Write two print statements to display the contents of toyBox and numberBox using their item properties.

Swift

struct Box {
    var item: Item
}

var toyBox = Box(item: "Teddy Bear")
var numberBox = Box(item: 42)

// Your code here

Need a hint?

Use print("Toy box contains: \(toyBox.item)") and similarly for numberBox.