What are the differences between iterators and arrays in JavaScript?

What are the differences between iterators and arrays in JavaScript?

In JavaScript, arrays are list-like objects that store multiple values, while iterators are objects that allow you to traverse through a collection, like an array, one element at a time.

Can you give me an example of how to use an iterator?

Sure! You can create an iterator using the Symbol.iterator method. For example, you can define a custom iterable object like this:

const myIterable = {
  *[Symbol.iterator]() {
    yield 1;
    yield 2;
    yield 3;
  }
};

for (const value of myIterable) {
  console.log(value);
}

What are the advantages of using iterators over arrays?

Iterators provide a more memory-efficient way to handle large datasets since they generate values on-the-fly rather than storing them all in memory like arrays. They also allow for more flexible data traversal.

Are there any built-in iterators in JavaScript?

Yes, JavaScript has built-in iterators for various data structures, such as arrays, maps, and sets. For example, you can use the Array.prototype.entries() method to get an iterator for an array's key-value pairs.