public function loadString($source)
    {
        $name = crc32($source);

        if(!$file = $this->isCached($name))
        {
            //Compile the template
            if(!$this->_source = $this->_compile($source)) {
                throw new RuntimeException(sprintf('The template content cannot be compiled.'));
            }

            $this->cache($name, $this->_source);
        }
        else  $this->_source = file_get_contents($file);

        return $this;
    }