// vars to "*"
static S upperCaseVarsToStars(S s, L<S> vars_out) {
  L<S> tok = javaTok(s);
  for (int i = 1; i < l(tok); i += 2) {
    S t = tok.get(i);
    if (startsWithUpperCase(t)) {
      listAdd(vars_out, t);
      tok.set(i, "*");
    }
  }
  ret join(tok);
}

static S upperCaseVarsToStars(S s) {
  ret upperCaseVarsToStars(s, null);
}