←
Beta
Home

Declaring and manipulating variables in programming is a fundamental concept that allows you to store and modify data. Variables in Rust are immutable by default, but you can make them mutable using the mut keyword.

In this challenge, you will declare and use mutable variables in Rust. You will be given a function where you need to declare variables, modify their values, and perform specific operations.

Your task

  • Declare variable text with an initial value of type String Use let mut to make it mutable.
  • Re assign the variable text to something else of your choice.
  • Call the mutates_value(&mut text) function, which will change the value of your text variable.
  • Return the final value of the variable.

Hints

If you're stuck, feel free to check out the hints below

<details> <summary>Click here to see the hints</summary>

  • Use the let mut keyword to declare a mutable variable.

  • To give the value to as a mutable reference use the &mut keyword. e.g.

    let mut text = "hello";
    mutates_value(&mut text);

  • To create a String from a &str, use String::from(value) or value.to_string(). e.g.

    let text = "hello";
    let text = text.to_string();

  • To return a value from a function, either use the return statement or let the last expression be the return value. For example:

    // Using return statement
    fn example1() -> String {
        return String::from("hello");
    }
    

    // Using expression (no semicolon)
    fn example2() -> String {
        String::from("hello")
    }
</details>
← PreviousNext →
pub fn mutating_variables() -> String {
    // 1. Declare a mutable variable `text` with value "hello"


    // 2. Call `mutates_value` with a mutable reference to `text`


    // 3. Return the value of `text` as a String
}


// Do not change this function
pub fn mutates_value(value: &mut String) {
    *value = String::from("bye")
}