<?php

  include_once('BookTitleDecorator.php');
  
  class BookTitleExclaimDecorator extends BookTitleDecorator {
	
	   private $btd;

    public function __construct(BookTitleDecorator $btd_in) {
	     $this->btd = $btd_in;
    }

    function exclaimTitle() {
	     $this->btd->title = "!" . $this->btd->title . "!";
	   }

  }
?>