Checking whether something is iterable

Question

In the MDN docs: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/for...of

The for...of construct is described to be able to

Answer 1

For async iterators you should check for the 'Symbol.asyncIterator' instead of 'Symbol.iterator':

async function* doSomething(i) {
    yield 1;
    yield 2;
}

let obj = doSomething();

console.log(typeof obj[Symbol.iterator] === 'function');      // false
console.log(typeof obj[Symbol.asyncIterator] === 'function'); // true