Recursive get() for symfony, ParameterBag modifications

ParameterBag.php

/**
 * Returns a parameter by name, or use : to search in arrays($request->get('form:somefield:anotherfield'))
 * $_POST[form][somefield][anotherfield]
 *
 * @param string $key     The key
 * @param mixed  $default The default value if the parameter key does not exist
 *
 * @return mixed
 */
public function get($key, $default = null)
    {
    	if(array_key_exists($key, $this->parameters)){
    		return $this->parameters[$key];
    	}
		
		if(strstr($key, ':')){
			$parameters = $this->parameters;
			foreach(explode(':', $key) as $segment){
				
				
				if(array_key_exists($segment, $parameters)){
					$parameters = $parameters[$segment];
				}else{
					return $default;
				}
			}
			
			return $parameters;
		}
		
		return $default;
}