Adding async array prototype methods

[jeremygottfried]

Objective

Add async methods that replicate array prototype iterators.

• aForEach
• aMap
• aReduce
• aFilter
• aEvery

These methods will have similar functionality to array prototypes iterators, but they can additionally carry out asynchronous tasks in order.

For example, the aReduce method will allow you to reduce an array asynchronously, which is currently not possible with array prototype.

const arr = [0,1,2,3];

async function callback(acc, current) {
  await new Promise(resolve => setTimeout(resolve, 0));
  return acc + current;
}

const reduce = aReduce(arr, callback); // => 6

Why

Most native array prototype iterators do not work well with async.
With forEach, you can schedule async tasks, but they will not occur in order.
With map, it returns an array of promises.
reduce doesn't work at all with async values.

User Experience

These methods will give users a more familiar interface for working with asynchronous iteration. Most javascript developers don't work with while loops on a regular basis.