public boolean isNested() {
    if (myChecked) {
      return myNested;
    }

    myChecked = true;

    if (myParents != null) {
      PsiFragment parent1 = myParents[0];
      PsiFragment parent2 = myParents[1];

      if (parent1 != null) {
        myNested |= parent1.myDuplicate || parent1.isNested();
        if (parent2 != null) {
          myNested |= parent2.myDuplicate || parent2.isNested();
        }
      }
    }

    return myNested;
  }
public boolean isNested()