public function only($keys = null)
    {
        $keys = is_array($keys) ? $keys : func_get_args();
        return array_only($this->params, $keys);
    }
public function only($keys = null)
    {
        $keys = is_array($keys) ? $keys : func_get_args();
        return array_only($this->params, $keys);
    }
public function only ( $ keys = null ) { $ keys = is_array ( $ keys ) ? $ keys : func_get_args ( ) ; return array_only ( $ this -> params , $ keys ) ; }
Get a subset of the items from the parameters.

@param  array  $keys
@return array
Get a subset of the items from the parameters .