How do I make this JS function asynchronous?

Question

function takesTime(){

    for (var i = 0; i

        

Answer 1

You can use web workers to achieve your objective, but you'll require a separate js file, and you'll have to add plumbing code to post messages and handle those messages.

node.js doesn't support web workers natively, but an implementation is available at:

https://github.com/cramforce/node-worker/

Otherwise, it's similar to the following code:

var pid = require('child_process').spawn('node', ['childScript.js'])
pid.stdout.on('data', function(data) {
  console.log(data);
});
console.log('b');

childScript.js

for (var i = 0; i < some_very_large_number; i++) {
  // do something synchronous
}
console.log('a');