isUsingShortSyntax example

if (\is_string($service) && str_starts_with($service, '@')) {
            $alias = new Alias(substr($service, 1));

            if (isset($defaults['public'])) {
                $alias->setPublic($defaults['public']);
            }

            return $return ? $alias : $this->container->setAlias($id, $alias);
        }

        if (\is_array($service) && $this->isUsingShortSyntax($service)) {
            $service = ['arguments' => $service];
        }

        if (!\is_array($service ??= [])) {
            throw new InvalidArgumentException(sprintf('A service definition must be an array or a string starting with "@" but "%s" found for service "%s" in "%s". Check your YAML syntax.', get_debug_type($service), $id, $file));
        }

        if (isset($service['stack'])) {
            if (!\is_array($service['stack'])) {
                throw new InvalidArgumentException(sprintf('A stack must be an array of definitions, "%s" given for service "%s" in "%s". Check your YAML syntax.', get_debug_type($service), $id, $file));
            }

            

if (\is_string($service) && str_starts_with($service, '@')) {
            $alias = new Alias(substr($service, 1));

            if (isset($defaults['public'])) {
                $alias->setPublic($defaults['public']);
            }

            return $return ? $alias : $this->container->setAlias($id, $alias);
        }

        if (\is_array($service) && $this->isUsingShortSyntax($service)) {
            $service = ['arguments' => $service];
        }

        if (!\is_array($service ??= [])) {
            throw new InvalidArgumentException(sprintf('A service definition must be an array or a string starting with "@" but "%s" found for service "%s" in "%s". Check your YAML syntax.', get_debug_type($service), $id, $file));
        }

        if (isset($service['stack'])) {
            if (!\is_array($service['stack'])) {
                throw new InvalidArgumentException(sprintf('A stack must be an array of definitions, "%s" given for service "%s" in "%s". Check your YAML syntax.', get_debug_type($service), $id, $file));
            }