rustHow to return error in Rust

Rust provides a number of ways to return errors. The most common way is to use the Result type. Result is an enum that can either be Ok or Err. Ok is used to indicate success and Err is used to indicate an error.

Code example:

fn divide(x: i32, y: i32) -> Result<i32, &'static str> {
    if y == 0 {
        return Err("Cannot divide by zero!");
    }
    Ok(x / y)
}

fn main() {
    let result = divide(10, 0);
    match result {
        Ok(val) => println!("Result: {}", val),
        Err(err) => println!("Error: {}", err),
    }
}

Output

Error: Cannot divide by zero!

Explanation:

1. The divide function takes two i32 parameters and returns a Result type. The Result type is an enum that can either be Ok or Err.
2. If the second parameter is 0, the function returns an Err with the message "Cannot divide by zero!".
3. If the second parameter is not 0, the function returns an Ok with the result of the division.
4. In the main function, the result of the divide function is stored in the result variable.
5. The match statement is used to check the value of the result variable.
6. If the result is Ok, the value is printed.
7. If the result is Err, the error message is printed.

Helpful links:

1. Rust Documentation - Result
2. Rust Documentation - Match

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