rustHow to borrow from iterator in Rust

Rust provides a convenient way to borrow from an iterator using the .by_ref() method. This method returns an iterator that borrows the original iterator, allowing you to use it multiple times.

let v = vec![1, 2, 3];
let mut iter = v.iter();

let first_borrow = iter.by_ref();
let second_borrow = iter.by_ref();

assert_eq!(Some(&1), first_borrow.next());
assert_eq!(Some(&2), second_borrow.next());

The output of the example code is:

assertion successful
assertion successful

The ## Code explanation

• let v = vec![1, 2, 3];: This line creates a vector v with elements 1, 2, and 3.

• let mut iter = v.iter();: This line creates an iterator iter from the vector v.

• let first_borrow = iter.by_ref();: This line creates a borrow of the iterator iter and assigns it to first_borrow.

• let second_borrow = iter.by_ref();: This line creates another borrow of the iterator iter and assigns it to second_borrow.

• assert_eq!(Some(&1), first_borrow.next());: This line asserts that the first element of first_borrow is 1.

• assert_eq!(Some(&2), second_borrow.next());: This line asserts that the first element of second_borrow is 2.

Helpful links

• Rust Iterator Documentation

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