gistfile1.txt

$ frogsh append.dart 
Elapsed time: 0.04
1500237.4288328215
$ cat append.dart 
main() {
  var nn = [];
  for (var i = 0; i < 3000000; i++) {
    nn.add(Math.random());
  }
  var sum = 0;
  var sw = new Stopwatch();
  sw.start();
  for (var n in nn) {
    sum += n;
  }
  sw.stop();
  print("Elapsed time: ${sw.elapsedInMs() / 1000}");
  print(sum);
}
$