private void doPerformChildrenGuidance(TreeTraversal.GuidedIt<T> it, Condition<? super T> expand) {
      if (it.curChild == null) return;
      if (forceIgnore != Cond.FALSE && forceIgnore.valueOr(it.curChild)) return;
      if (it.curParent == null || expand == Conditions.alwaysTrue() || expand.value(it.curChild)) {
        it.queueNext(it.curChild);
      }
      else {
        it.result(it.curChild);
      }
    }
private void doPerformChildrenGuidance(TreeTraversal.GuidedIt<T> it, Condition<? super T> expand)