Day 14: Timeout Cancellation

Given a function fn, an array of arguments args, and a timeout t in milliseconds, return a cancel function cancelFn.

After a delay of t, fn should be called with args passed as parameters unless cancelFn was invoked before the delay of t milliseconds elapses, specifically at cancelT ms. In that case, fn should never be called.

var cancellable = function(fn, args, t) {
    
};

Example 1:
Input: fn = (x) => x * 5, args = [2], t = 20, cancelT = 50
Output: [{"time": 20, "returned": 10}]

Example 2:
Input: fn = (x) => x*/*2, args = [2], t = 100, cancelT = 50
Output: []

Example 3:
Input: fn = (x1, x2) => x1 * x2, args = [2,4], t = 30, cancelT = 100
Output: [{"time": 30, "returned": 8}]

var cancellable = function(fn, args, t) {
  const cancelFn = function () {
      clearTimeout(timer);
  };
  const timer = setTimeout(() => {
      fn(...args)
  }, t);
  return cancelFn;
};