This function lets you create a promise and, at a later time, set its resolve value and resolve the promise.
// Make deferred promise
var x = makeDeferredPromise();
// Set resolve value
x.setResolveValue('Sandwich');
// Do something on resolve
x.then((value) => console.log(value));
// Resolve promise
x.resolve(); // 'Sandwich'
Promise status: pending
Value to resolve with: pending
Resolved with: n/a