static BasicLogicRule<S> ai_sharedPhrasesIntoDollarVars(BasicLogicRule<S> r) {
  LS phrases = antiFilter isDollarVar(sharedPhrases(r.lhs, r.rhs));
  SS map = ciMapWithUnusedCountingDollarVars(phrases, linesLL(r.lhs, r.rhs));
  ret mapBasicLogicRule(r, s -> replaceCodeTokensUsingMap(s, map));
}