get_padding static method
Implementation
static String get_padding(int count, String pad) {
  var padding_piece = pad;
  var padding = StringBuffer();
  while (count > 0) {
    if ((count & 1) == 1) {
      padding.write(padding_piece);
    }
    count >>= 1;
    padding_piece = '${padding_piece}${padding_piece}';
  }
  return padding.toString();
}