guard() {
    freeze(this.attributes);
    GuardedState.set(this, true);
    return this;
  }
/**
   * Makes attributes guarded. Attributes cannot be mutated.
   * @return {Bag}
   */
Makes attributes guarded. Attributes cannot be mutated.
@return {Bag}
Makes attributes guarded . Attributes cannot be mutated . @return { Bag }
guard() {
    freeze(this.attributes);
    GuardedState.set(this, true);
    return this;
  }
guard ( ) { freeze ( this . attributes ) ; GuardedState . set ( this , true ) ; return this ; }
Makes attributes guarded.
Makes attributes guarded .