Serializing error when using retrieve($key, true)

[Sean]

Thanks for this wonderful and simple caching library. It's exactly what I need!

Just FYI, this notice occurs on line 105 of cache.class.php in my version
of PHP, 5.6.14.

The fix is to only serialize when $type == 'data'. My quick fix was this:

 /**
   * Retrieve cached data by its key
   * 
   * @param string $key
   * @param boolean [optional] $timestamp
   * @return string
   */
  public function retrieve($key, $timestamp = false) {
    $cachedData = $this->_loadCache();
    (false === $timestamp) ? $type = 'data' : $type = 'time';
    if (!isset($cachedData[$key][$type])) return null; 

    if ($type == 'time') {
        return $cachedData[$key][$type];
    }
    return unserialize($cachedData[$key][$type]);
  }

[XerraX]

saved me some time, still using this script ^^