```
2021.10.22 07:14:33.963099 [ 3451059 ] {} <Error> Application: DB::Exception: Syntax error (in file ./user_defined/function_a_function.sql): failed at position 39 ('->'): -> ch(2)

$ cat ./user_defined/function_a_function.sql
CREATE FUNCTION a_function AS tuple() -> ch(2)
```
std::string nl_or_nothing = settings.one_line ? "" : "\n";
        std::string indent_str = settings.one_line ? "" : std::string(4u * frame.indent, ' ');
        settings.ostr << (settings.hilite ? hilite_function : "") << name << "(" << nl_or_nothing;
        FormatStateStacked frame_nested = frame;
        frame_nested.need_parens = false;
        ++frame_nested.indent;
        query->formatImpl(settings, state, frame_nested);
        settings.ostr << nl_or_nothing << indent_str << ")";
        return;
    }
    
    bool written = false;
    if (arguments && !parameters)
    {
        
        if (arguments->children.size() == 1)
        {
            const char * operators[] =
            {
                "negate",      "-",
                "not",         "NOT ",
                nullptr
            };
            for (const char ** func = operators; *func; func += 2)
            {
                if (strcasecmp(name.c_str(), func[0]) != 0)
                {
                    continue;
                }
                const auto * literal = arguments->children[0]->as<ASTLiteral>();