What are custom iterable objects in JavaScript?

Can you explain what custom iterable objects are in JavaScript?

Sure! Custom iterable objects in JavaScript are objects that implement the iterable protocol, allowing them to be used in loops like for...of.

How do I create a custom iterable object?

To create a custom iterable, you need to define a method called Symbol.iterator that returns an iterator object.

Can you give me an example of a custom iterable?

Absolutely! Here's a simple example:

class MyIterable {
  constructor(data) {
    this.data = data;
  }
  [Symbol.iterator]() {
    let index = 0;
    return {
      next: () => {
        if (index < this.data.length) {
          return { value: this.data[index++], done: false };
        } else {
          return { done: true };
        }
      }
    };
  }
}
const myIterable = new MyIterable([1, 2, 3]);
for (const value of myIterable) {
  console.log(value);
}

What are some use cases for custom iterable objects?

Custom iterable objects can be useful for creating collections that can be easily traversed, like data structures or APIs that return data in a specific format.