Method addAndReplace

classpath/java/util/TreeSet.java:76–86

(T value)

  }

  T addAndReplace(T value) {
    PersistentSet.Path<Cell<T>> p = set.find(new Cell(value, null));
    if (p.fresh()) {
      set = p.add();
      return null;
    } else {
      T old = p.value().value;
      set = p.replaceWith(new Cell(value, null));
      return old;
    }
  }
    
  T find(T value) {
    PersistentSet.Path<Cell<T>> p = set.find(new Cell(value, null));