What are JavaScript iterators and how do they work?

What are JavaScript iterators and how do they work?

JavaScript iterators are objects that allow you to traverse through a collection, like arrays or strings, one element at a time.

Can you give me an example of how to create a custom iterator?

Sure! You can create a custom iterator by defining a function that returns an object with a next method. Here's a simple example:

function createIterator(array) {
    let index = 0;
    return {
        next: function() {
            if (index < array.length) {
                return { value: array[index++], done: false };
            } else {
                return { done: true };
            }
        }
    };
}

What does the done property signify in the iterator's output?

The done property indicates whether the iterator has completed traversing the collection. If done is true, it means there are no more elements to iterate over.

How do iterators differ from generators in JavaScript?

Iterators are objects with a next method, while generators are a special type of function that can pause and resume execution, automatically creating an iterator.