public function getRegisteredParsers()
    {
        if ($this->parserInstances === null) {
            $result = [];
            foreach ($this->parsers as $parser) {
                if ($parser instanceof ParserInterface) {
                    $result[] = $parser;
                } else {
                    $instance = $this->app->make($parser);
                    if (!($instance instanceof ParserInterface)) {
                        throw new UserMessageException(t(/*i18n: %1$s is the name of a PHP class, %2$s is the name of a PHP interface*/'%1$s does not implement %2$s', $parser, ParserInterface::class));
                    }
                    $result[] = $instance;
                }
            }
            $this->parserInstances = $result;
        } else {
            $result = $this->parserInstances;
        }

        return $result;
    }