sbool ai_ruleAccessesInput(S rule) {
  L<S> tok = javaTokC(rule);
  S t;
  for i over tok:
    if (eqGet(tok, i+1, "(") && isIdentifier(t = tok.get(i)))
      if (swic(t, "input") || ewic(t, "input")) true;
  false;
}