Difference between Javascript async functions and Web workers?

Question

Threading-wise, what\'s the difference between web workers and functions declared as

async function xxx()
{
}

?

I am aware web worker

Answer 1

Here is a way to call standard functions as workers, enabling true parallelism. It's an unholy hack written in blood with help from satan, and probably there are a ton of browser quirks that can break it, but as far as I can tell it works.

[constraints: the function header has to be as simple as function f(a,b,c) and if there's any result, it has to go through a return statement]

function Async(func, params, callback)
{ 
 // ACQUIRE ORIGINAL FUNCTION'S CODE
 var text = func.toString(); 


 // EXTRACT ARGUMENTS
 var args = text.slice(text.indexOf("(") + 1, text.indexOf(")")); 
 args     = args.split(",");
 for(arg of args) arg = arg.trim();


 // ALTER FUNCTION'S CODE:
 // 1) DECLARE ARGUMENTS AS VARIABLES
 // 2) REPLACE RETURN STATEMENTS WITH THREAD POSTMESSAGE AND TERMINATION
 var body = text.slice(text.indexOf("{") + 1, text.lastIndexOf("}")); 
 for(var i = 0, c = params.length; i

So, assuming you have this potentially cpu intensive function...

function HeavyWorkload(nx, ny) 
{
 var data = [];

 for(var x = 0; x < nx; x++)
 {
  data[x] = [];

  for(var y = 0; y < ny; y++)
  {
   data[x][y] = Math.random();
  }
 }

 return data;
}

...you can now call it like this:

Async(HeavyWorkload, [1000, 1000],
function(result)
{
 console.log(result);
}
);