SOURCE

function bouncer(arr) {
  // Don't show a false ID to this bouncer.
  var a = [];
  var count = 0;
  for (var i = 0; i < arr.length; i++) {
    if (arr[i]) {
      console.log(count);
      a[count] = arr[i];
      count++;
    }
  }
  return a;
}
bouncer([7, "ate", "", false, 9]);