Properly pass variables into extracted function

[Undin]

We always pass variables by value and it can lead to incorrect code.
We should correctly determine how to pass variable: by value or by reference.

fn foo() {
    let vec = vec![1, 2, 3];
    <selection>println!("{}", vec.len());</selection>
    println!("{}", vec[0]);
}

Expected:

fn foo() {
    let vec = vec![1, 2, 3];
    bar(&vec);
    println!("{}", vec[0]);
}

fn bar(vec: &Vec<i32>) {
    println!("{}", vec.len());
}

Actual:

fn foo() {
    let vec = vec![1, 2, 3];
    bar(vec);
    println!("{}", vec[0]); // error[E0382]: use of moved value: `vec`
}

fn bar(vec: Vec<i32>) {
    println!("{}", vec.len()); 
}

[t-kameyama]

I will work on this