static S swapFirstTwoLongs(S s) {
  L<S> tok = javaTok(s);
  int i = 1;
  while (i < l(tok) && !isInteger(tok.get(i))) i += 2;
  int j = i+2;
  while (j < l(tok) && !isInteger(tok.get(j))) j += 2;
  if (j >= l(tok)) ret s;
  swapElements(tok, i, j);
  ret join(tok);
}