JavaScript: async/await with forEach()

async-foreach.js

const waitFor = (ms) => new Promise(r => setTimeout(r, ms))
const asyncForEach = async (array, callback) => {
  for (let index = 0; index < array.length; index++) {
    await callback(array[index], index, array)
  }
}

const start = async () => {
  await asyncForEach([1, 2, 3], async (num) => {
    await waitFor(50)
    console.log(num)
  })
  console.log('Done')
}

start()

Here's my typescript version (Basically @wodCZ's codeblock) with the ability to return data which is readable in the form of an array

async function asyncForEach<T = any>(array: T[], callback: (value: T, index?: number, array?: T[]) => any): Promise<any[]> {
  const data: any[] = [];
  for (let index = 0; index < array.length; index++) {
    await (async () => {
      const item = await callback(array[index], index, array);
      if (item !== undefined) data.push(item);
      return;
    })();
  }
  return Promise.resolve(data);
}

I feel like this is just a glorified promise.all at this point.

Why not use for await()?

const waitFor = (ms) => new Promise(r => setTimeout(r, ms))
const start = async () => {
  for await (num of [1, 2, 3]) {
    await waitFor(50)
    console.log(num)
  };
  console.log('Done')
}
start()

More info here