main function and entry point in Rust - Mini Project: Build & Apply

Understanding the main function and entry point in Rust

📖 Scenario: You are creating a simple Rust program that prints a welcome message. Every Rust program starts running from a special function called main. This project will help you learn how to write the main function and run code inside it.

🎯 Goal: Build a Rust program with a main function that prints the message "Welcome to Rust programming!" when run.

📋 What You'll Learn

Create a main function as the entry point

Use println! macro inside main to print the message

Print exactly: Welcome to Rust programming!

💡 Why This Matters

🌍 Real World

Every Rust program, from small tools to big applications, starts running from the <code>main</code> function. Knowing how to write it is essential.

💼 Career

Understanding the <code>main</code> function is a fundamental skill for Rust developers, needed in software development, systems programming, and more.

1

Create the main function

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

Rust

fn main() {
    // Your code here
}

Need a hint?

The main function is the starting point of a Rust program. It always looks like fn main() { }.

2

Add a print statement inside main

Inside the main function, add a line using println! macro to print the exact text "Welcome to Rust programming!".

Rust

fn main() {
    // Your code here
}

Need a hint?

Use println!("text") to print text to the screen in Rust.

3

Run the program to see the output

Run the Rust program so it executes the main function and prints the message. No code change needed here, just understand the flow.

Rust

fn main() {
    println!("Welcome to Rust programming!");
    // Run the program to see output
}

Need a hint?

Running the program will start at main and print the message.

4

Print the output

Print the output of the program by running it. The output should be exactly Welcome to Rust programming!.

Rust

fn main() {
    println!("Welcome to Rust programming!");
}

// Print the output below

Need a hint?

When you run the program, the console shows the printed message.