Rc pointer in Rust - Mini Project: Build & Apply

Understanding Rc Pointer in Rust

📖 Scenario: You are building a simple program to share ownership of a value between multiple parts of your code safely.Rust's Rc pointer helps you do this by keeping track of how many owners a value has.

🎯 Goal: Learn how to create an Rc pointer, clone it to share ownership, and check the reference count.

📋 What You'll Learn

Create an Rc pointer with a string value

Clone the Rc pointer to share ownership

Check the reference count using Rc::strong_count

Print the reference count to see how many owners exist

💡 Why This Matters

🌍 Real World

Sharing data safely between parts of a program without copying it multiple times.

💼 Career

Understanding Rc pointers is important for Rust developers working on applications that need shared ownership without using threads.

1

Create an Rc pointer

Write code to create an Rc pointer called shared_name that holds the string "Rustacean". Use Rc::new to create it.

Rust

use std::rc::Rc;

fn main() {
    // Create an Rc pointer called shared_name holding "Rustacean"
    // Your code here
}

Hint

Use Rc::new(String::from("Rustacean")) to create the pointer.

2

Clone the Rc pointer

Add code to clone the Rc pointer shared_name into a new variable called shared_name_clone. This shares ownership of the same string.

Rust

use std::rc::Rc;

fn main() {
    let shared_name = Rc::new(String::from("Rustacean"));
    // Clone shared_name into shared_name_clone
    // Your code here
}

Hint

Use Rc::clone(&shared_name) to clone the pointer.

3

Check the reference count

Add code to create a variable called count that stores the number of owners of the value inside shared_name. Use Rc::strong_count(&shared_name).

Rust

use std::rc::Rc;

fn main() {
    let shared_name = Rc::new(String::from("Rustacean"));
    let shared_name_clone = Rc::clone(&shared_name);
    // Get the reference count into count
    // Your code here
}

Hint

Use Rc::strong_count(&shared_name) to get the number of owners.

4

Print the reference count

Write a println! statement to display the text "Reference count: {count}" where {count} is the value of the variable count.

Rust

use std::rc::Rc;

fn main() {
    let shared_name = Rc::new(String::from("Rustacean"));
    let shared_name_clone = Rc::clone(&shared_name);
    let count = Rc::strong_count(&shared_name);
    // Print the reference count
    // Your code here
}

Hint

Use println!("Reference count: {}", count); to show the count.