rustlings/exercises/move_semantics/move_semantics4.rs

// move_semantics4.rs
// Refactor this code so that instead of having `vec0` and creating the vector
// in `fn main`, we create it within `fn fill_vec` and transfer the
// freshly created vector from fill_vec to its caller.
// Execute `rustlings hint move_semantics4` for hints!

// // original code
// fn main() {
//     let vec0 = Vec::new();

//     let mut vec1 = fill_vec(vec0);

//     println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);

//     vec1.push(88);

//     println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
// }

// // original code (cont'd)
// // `fill_vec()` no longer takes `vec: Vec<i32>` as argument
// fn fill_vec() -> Vec<i32> {
//     let mut vec = vec;

//     vec.push(22);
//     vec.push(44);
//     vec.push(66);

//     vec
// }
// // end of original code

// solution
fn main() {
    let mut vec1 = fill_vec();

    println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);

    vec1.push(88);

    println!("{} has length {} content `{:?}`", "vec1", vec1.len(), vec1);
}

// solution (cont'd)
// `fill_vec()` no longer takes `vec: Vec<i32>` as argument
fn fill_vec() -> Vec<i32> {
    // create mutable vec
    let mut vec = Vec::new();

    vec.push(22);
    vec.push(44);
    vec.push(66);

    vec
}
// end of solution