private function callHandlers(string $keyword, int $strategy)
    {
        if ($this->handlers)
        {
            $stack = null;
            foreach($this->handlers as $handler){
                $replace = $handler($keyword);
                if (!is_null($replace)){
                    if ($strategy === EnumMacroProcessStorategy::STRATEGY_FISRT){
                        return $replace;
                    }
                    $stack[] = $replace;
                }
            }
            if ($strategy === EnumMacroProcessStorategy::STRATEGY_LAST && !empty($stack)){
                return array_pop($stack);
            }
        }
        return null;
    }