sbool nlLogic_checkFirstConditions2_debug;

// returns (number of succeeded conditions, remaining conditions)
static Pair<Int, Exp> nlLogic_checkFirstConditions2(NLLogicChecker_v2 c, IfThen rule, NLLogicChecker_v2.Matching m) {
  Exp exp = rule.in;
  int succeeded = 0;
  while ping (exp != null) {
    Pair<Bool, Exp> p = c.checkFirstCondition(exp, m);
    if (nlLogic_checkFirstConditions2_debug)
      print("nlLogic_checkFirstConditions2: exp=" + exp + ", p=" + p);
    if (!p.a) break;
    ++succeeded;
    exp = p.b;
  }
  ret pair(succeeded, exp);
}

Began life as a copy of #1018054