What are iterable patterns in JavaScript?

What are iterable patterns in JavaScript?

Iterable patterns in JavaScript refer to the ways in which objects can be iterated over, typically using the for...of loop or other iteration methods.

Can you give me an example of an iterable object?

Sure! Arrays and strings are common iterable objects. For example, you can iterate over an array like this: for (const item of array) { console.log(item); }.

What about custom iterable objects?

You can create custom iterable objects by implementing the Symbol.iterator method. This allows you to define how the object should be iterated.

Can you show me a code example for a custom iterable?

Absolutely! Here's a simple example:

class MyIterable {
    constructor() {
        this.items = [1, 2, 3];
    }
    [Symbol.iterator]() {
        let index = 0;
        return {
            next: () => {
                if (index < this.items.length) {
                    return { value: this.items[index++], done: false };
                } else {
                    return { done: true };
                }
            }
        };
    }
}

const iterable = new MyIterable();
for (const item of iterable) {
    console.log(item);
}