What are iterators and generators in JavaScript?

What are iterators and generators in JavaScript?

Iterators are objects that allow you to traverse through a collection, like arrays. Generators are a special type of function that can be paused and resumed, making it easier to create iterators.

Can you give me an example of a generator function?

Sure! Here's a simple generator function:

function* countUpTo(max) {
  let count = 1;
  while (count <= max) {
    yield count;
    count++;
  }
}

This function yields numbers from 1 to the specified max.

How do I use the generator function?

You can use it like this:

const counter = countUpTo(5);
for (let num of counter) {
  console.log(num);
}

This will log numbers 1 through 5 to the console.

What are the benefits of using generators?

Generators are memory efficient because they yield values one at a time, and they can represent infinite sequences, making them very powerful for certain tasks.