How can I work with advanced iterable objects in TypeScript?

How can I work with advanced iterable objects in TypeScript?

In TypeScript, you can create advanced iterable objects by implementing the iterable protocol. This involves defining a Symbol.iterator method that returns an iterator object.

Can you show me an example of an iterable object?

Sure! Here's a simple example:

class MyIterable {
    private data: number[];

    constructor(data: number[]) {
        this.data = data;
    }

    [Symbol.iterator]() {
        let index = 0;
        const data = this.data;
        return {
            next(): IteratorResult<number> {
                if (index < data.length) {
                    return { value: data[index++], done: false };
                } else {
                    return { value: undefined, done: true };
                }
            }
        };
    }
}

const iterable = new MyIterable([1, 2, 3]);
for (const value of iterable) {
    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 iterated over, such as data structures like trees or graphs, or for implementing lazy evaluation.

How do I handle asynchronous iterables in TypeScript?

You can handle asynchronous iterables in TypeScript by using the AsyncIterable interface and the for await...of loop. This allows you to work with data that is fetched asynchronously.