Built-in entries iterator in JavaScript

All iterables have the built-in entries iterator that allows you to iterate over key-value pairs. Let's test it on an array:

let arr = ['a', 'b', 'c'];

We get an iterator:

let iter = arr.entries();

And loop through it:

for (let entry of iter) { console.log(entry); // [0, 'a'], [1, 'b'], [2, 'c'] }

Let's perform destructuring during iteration:

for (let [key, value] of iter) { console.log(key); // 'a', 'b', 'c' console.log(value); // 0, 1, 2 }

Test the work of this iterator on a Map collection.

Test the work of this iterator on a Set collection.

Test the work of this iterator on a NodeList collection.

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