Error handling in Rust Options

err-option.rs

fn main() {
    // first let's define vector/array of numbers
    let numbers = vec![1, 2, 4];

    // now let's try to read value from vector
    let index_one = numbers[1];
    println!("value at index {}", index_one);

    // now let's try to read 10th index which doesn't exists
    // since Rust doesn't have neither null nor try/catch to handle error
    // so we will take leverage of **Option**
    
    // un comment below two line to check error

    // let out_of_index = numbers[10];
    // println!("this will throw error {}", out_of_index);

    // above code would result in following error
    // thread 'main' panicked at 'index out of bounds: the len is 3 but the index is 10'

    // rust has very interesting way to handle these errors
    // we will take advantage of Option and get method from
    // vector to handle these kind of errors

    // get method of vector returns **Option** enum
    // Option will have two properties Some and None
    // let's see how to read/catch error
    match numbers.get(10) {
        Some(value) => println!("Hello {}", value),
        None => println!("Yo!! out of bound error")
    }

    // now let's see how to read value from it
    let result = match numbers.get(10) {
        Some(value) => value,
        None => &-1 // defaulting to -1
    };

    println!("result is {}", result);

    // as you can see above code works well but,
    // we can improve code by taking advantage of Result
}