Array.at() - Negative Indexing in JavaScript

const items = ['a', 'b', 'c', 'd', 'e'];

// The old way
const last = items[items.length - 1]; // 'e'
const secondLast = items[items.length - 2]; // 'd'

const items = ['a', 'b', 'c', 'd', 'e'];

// Clean and readable
const last = items.at(-1); // 'e'
const secondLast = items.at(-2); // 'd'
const first = items.at(0); // 'a'

// Get last item in a list
const users = await fetchUsers();
const newest = users.at(-1);

// Get file extension
const parts = filename.split('.');
const ext = parts.at(-1);

// Circular array access
function getItem(arr, index) {
  return arr.at(index % arr.length);
}

const str = 'Hello';

str.at(0);  // 'H'
str.at(-1); // 'o'
str.at(-2); // 'l'