# shuffle method

void shuffle ([Random random ])

Shuffles the elements of this list randomly.

## Implementation

    void shuffle([Random random]) {
      if (random == null) random = new Random();
      int length = this.length;
      while (length > 1) {
        int pos = random.nextInt(length);
        length -= 1;
        var tmp = this[length];
        this[length] = this[pos];
        this[pos] = tmp;
      }
    }