Program structure in Rust - Mini Project: Build & Apply

Understanding Program Structure in Rust

📖 Scenario: You are learning how to write a simple Rust program. Rust programs start with a main function where the code runs. You will create a basic program that prints a greeting message.

🎯 Goal: Build a Rust program with a main function that prints Hello, Rust! to the screen.

📋 What You'll Learn

Create a main function

Use println! macro to print text

Print exactly Hello, Rust!

💡 Why This Matters

🌍 Real World

Every Rust program starts with a <code>main</code> function. This structure is the foundation for building command-line tools, servers, and more.

💼 Career

Understanding program structure is essential for any Rust developer. It helps you organize code and build applications that run correctly.

1

Create the main function

Write a fn main() function with empty curly braces {} to start your Rust program.

Rust

fn main() {
    // Your code here
}

Need a hint?

The main function is the entry point of a Rust program. It always starts with fn main() followed by curly braces.

2

Add a print statement inside main

Inside the main function, write println!("Hello, Rust!"); to print the greeting message.

Rust

fn main() {
    // Your code here
}

Need a hint?

The println! macro prints text to the screen. Remember to include the exclamation mark and the semicolon.

3

Check the program structure

Make sure your program has the fn main() function and inside it the line println!("Hello, Rust!");.

Rust

fn main() {
    println!("Hello, Rust!");
    // Your code here
}

Need a hint?

Double-check that your print statement is inside the main function and spelled exactly.

4

Run and display the output

Run the program and print the output. Write println!("Hello, Rust!"); inside main and then run it to see the message.

Rust

fn main() {
    println!("Hello, Rust!");
}

// Run the program to see the output

Need a hint?

When you run the program, the console should show Hello, Rust!.