Traits - decorator pattern

gistfile1.aw

<?php

interface IDecoratedText
{
  public function __toString();
}

trait TextDecorator
{
  protected $text = null;

  public function __construct(IDecoratedText $text)
  {
    $this->text = $text;
  }
}

class Text implements IDecoratedText 
{
  private $_str = 'World';

  public function __construct($str = '')
  {
    if ($str != '') {
      $this->_str = $str;
    }
  }

  public function __toString()
  {
    return sprintf('Hello, %s!', $this->_str);
  }
}

class HtmlText implements IDecoratedText
{
  use TextDecorator;

  public function __toString()
  {
    return sprintf('<b>%s</b>', $this->text->__toString());
  }
}

class JsonDecorator implements IDecoratedText
{
  use TextDecorator;

  public function __toString()
  {
    return json_encode($this->text->__toString());
  }
}

$text = new Text();
$text = new HtmlText($text);
$text = new JsonDecorator($text);

echo $text;