Rust Function: Check Option Some or None

Last update on December 21 2024 10:22:36 (UTC/GMT +8 hours)

Write a Rust function that takes an Option and returns "Some" if it's Some(i32) and "None" otherwise.

Sample Solution:

Rust Code:

// Function that checks if the input is Some(i32) or None and returns a corresponding string.
fn check_option(option: Option<i32>) -> &'static str {
    match option {
        Some(_) => "Some",
        None => "None",
    }
}

fn main() {
    // Example usage
    let some_value = Some(100);
    let none_value: Option<i32> = None;
    
    println!("For Some(100): {}", check_option(some_value)); // Output: Some
    println!("For None: {}", check_option(none_value));     // Output: None
}

Output:

For Some(100): Some
For None: None

Explanation:

In the exercise above,

• The "check_option()" function takes an Option<i32> as input and returns a string indicating whether the input is 'Some(i32)' or 'None'.
• Inside the function, a 'match' expression is used to pattern match the input 'Option'. If the input is 'Some(_)', meaning it contains a value, it returns "Some". If the input is None, it returns "None".
• In the "main()" function, two examples are demonstrated: one with a 'Some' value (Some(100)) and one with a 'None' value. The "check_option()" function is called with each example, and the result is printed to the console.

Rust Code Editor:

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