Rust Iterator Ownership: iter, iter_mut, and into_iter

Wed, 02 Sep 2026 00:00:00 +0700

Rust iteration becomes much easier once iterator choice is connected to ownership. For a collection such as Vec<T>, the central question is whether the loop should borrow values, mutate them in place, or consume the collection.

The common methods are iter(), iter_mut(), and into_iter().

Borrow with `iter()`

iter() produces shared references:

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fn print_names(names: &[String]) {
    for name in names.iter() {
        println!("{name}");
    }
}

Inside the loop, name has type &String.

Iterators on Nalar

Rust Iterator Ownership: iter, iter_mut, and into_iter

Borrow with iter()

Borrow with `iter()`