Variable shadowing in Rust - Mini Project: Build & Apply

Variable shadowing

📖 Scenario: Imagine you are organizing a small event and need to keep track of the number of guests. Sometimes, you update the count temporarily for calculations without changing the original number.

🎯 Goal: You will create a variable to hold the initial guest count, then shadow it with a new value to show how variable shadowing works in Rust. Finally, you will print the final guest count.

📋 What You'll Learn

Create a variable called guest_count with the value 50.

Shadow the variable guest_count by creating a new variable with the same name and assign it the value guest_count + 10.

Print the value of guest_count.

💡 Why This Matters

🌍 Real World

Variable shadowing helps when you want to reuse a variable name for updated values without changing the original variable's mutability.

💼 Career

Understanding shadowing is important for writing clear and safe Rust code, which is valuable in systems programming and software development jobs.

1

Create the initial guest count variable

Create a variable called guest_count and set it to 50.

Rust

# Create a variable called guest_count and set it to 50
# Your code here

Need a hint?

Use let guest_count = 50; to create the variable.

2

Shadow the guest_count variable

Shadow the variable guest_count by creating a new variable with the same name and assign it the value guest_count + 10.

Rust

fn main() {
    let guest_count = 50;
    // Shadow guest_count by adding 10
    // Your code here
}

Need a hint?

Use let guest_count = guest_count + 10; to shadow the variable.

3

Print the guest_count variable

Use println! to print the value of guest_count.

Rust

fn main() {
    let guest_count = 50;
    let guest_count = guest_count + 10;
    // Print guest_count
    // Your code here
}

Need a hint?

Use println!("{}", guest_count); to print the value.

4

Run the program to see the output

Run the program and observe the printed output showing the final guest count.

Rust

fn main() {
    let guest_count = 50;
    let guest_count = guest_count + 10;
    println!("{}", guest_count);
    // Your code here
}

Need a hint?

The output should be 60 because the variable was shadowed with guest_count + 10.