Optional elements in tuples in Typescript - Mini Project: Build & Apply

Optional elements in tuples

📖 Scenario: Imagine you are creating a simple system to store information about books. Some books have a subtitle, but not all. You want to use a tuple to store the title and optionally the subtitle.

🎯 Goal: Build a TypeScript tuple that can hold a book's title and optionally its subtitle using optional elements in tuples.

📋 What You'll Learn

Create a tuple type called Book with a required string for the title and an optional string for the subtitle.

Create a variable called book1 of type Book with only the title.

Create a variable called book2 of type Book with both title and subtitle.

Print both book1 and book2 to the console.

💡 Why This Matters

🌍 Real World

Optional tuple elements help model data where some parts may or may not be present, like subtitles in book titles.

💼 Career

Understanding optional tuple elements is useful for TypeScript developers working with flexible data structures in real-world applications.

1

Create the tuple type with an optional element

Create a tuple type called Book with a required string for the title and an optional string for the subtitle using the syntax [string, string?].

Typescript

# Your code here
// Create the tuple type Book with optional subtitle

Need a hint?

Use string? to mark the subtitle as optional in the tuple type.

2

Create a tuple variable with only the title

Create a variable called book1 of type Book and assign it a tuple with only the title 'The Great Gatsby'.

Typescript

type Book = [string, string?];
# Your code here
// Create book1 with only the title

Need a hint?

Assign a tuple with one string element to book1.

3

Create a tuple variable with title and subtitle

Create a variable called book2 of type Book and assign it a tuple with the title 'The Hobbit' and subtitle 'There and Back Again'.

Typescript

type Book = [string, string?];
const book1: Book = ['The Great Gatsby'];
# Your code here
// Create book2 with title and subtitle

Need a hint?

Assign a tuple with two string elements to book2.

4

Print both tuples to the console

Write two console.log statements to print book1 and book2 to the console.

Typescript

type Book = [string, string?];
const book1: Book = ['The Great Gatsby'];
const book2: Book = ['The Hobbit', 'There and Back Again'];
# Your code here
// Print book1 and book2

Need a hint?

Use console.log(book1); and console.log(book2); to show the tuples.