public function addTime($function, $start_time, $task)
    {
        if (!($function = trim((string) $function))) {
            return; // Not possible.
        }
        if (($start_time = (float) $start_time) <= 0) {
            return; // Not possible.
        }
        if (($end_time = (float) microtime(true)) <= 0) {
            return; // Not possible.
        }
        if (!($task = trim((string) $task))) {
            return; // Not possible.
        }
        $time                   = number_format($end_time - $start_time, 5, '.', '');
        $this->times[$function] = compact('function', 'time', 'task');
    }