Rust Program: Option Enum

Last update on December 21 2024 10:21:08 (UTC/GMT +8 hours)

Write a Rust program that creates an enum Option with variants representing some and none states.

Sample Solution:

Rust Code:

// Define an enum named 'Option' with variants representing 'Some' and 'None' states
enum Option<T> {
    Some(T),
    None,
}

fn main() {
    // Example usage: Create variables representing 'Some' and 'None' states
    let some_value: Option<i32> = Option::Some(42);
    let none_value: Option<i32> = Option::None;

    // Print the values of the variables
    match some_value {
        Option::Some(val) => println!("Some value: {}", val),
        Option::None => println!("No value"),
    }

    match none_value {
        Option::Some(val) => println!("Some value: {}", val),
        Option::None => println!("No value"),
    }
}

Output:

Some value: 42
No value

Explanation:

Here is a brief explanation of the above Rust code:

• We define an enum Option<T> with generic type 'T', which represents the type of value that 'Some' variant holds.
• We define two variants: Some(T) to hold a value of type 'T', and 'None' to represent the absence of a value.
• In the "main()" function, we create variables 'some_value' and 'none_value' representing instances of 'Option' enum with values in 'Some' and 'None' states, respectively.
• We use pattern matching (match expressions) to print the values of these variables. If the variable is in 'Some' state, we extract and print the inner value; if it's in 'None' state, we print a message indicating the absence of a value.

Rust Code Editor:

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