Iterator Patterns

Patterns สำหรับ iterator usage

Basic Iteration Patterns

fn main() {
    let numbers = vec![1, 2, 3, 4, 5];

    // for loop (uses IntoIterator)
    for n in &numbers {
        print!("{} ", n);
    }
    println!();

    // Explicit iterator
    let mut iter = numbers.iter();
    while let Some(n) = iter.next() {
        print!("{} ", n);
    }
    println!();

    // Three ways to iterate
    let vec = vec![1, 2, 3];

    for v in &vec { /* &T */ }        // Borrow
    for v in &mut vec.clone() { /* &mut T */ }  // Mut borrow
    for v in vec.clone() { /* T */ }  // Take ownership

    // iter(), iter_mut(), into_iter()
    let v = vec![1, 2, 3];

    let _ = v.iter();       // &i32
    let _ = v.clone().into_iter();  // i32 (owned)

    let mut v = v;
    let _ = v.iter_mut();   // &mut i32
}