```
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)
```
writeChar('(', ostr);
    if (arguments)
    {
        for (auto it = arguments->children.begin(); it != arguments->children.end(); ++it)
        {
            if (it != arguments->children.begin())
                writeCString(", ", ostr);
            (*it)->appendColumnName(ostr);
        }
    }
    writeChar(')', ostr);
    if (is_window_function)
    {
        writeCString(" OVER ", ostr);
        if (!window_name.empty())
        {
            ostr << window_name;
        }
        else
        {
            FormatSettings format_settings{ostr, true };
            FormatState state;
            FormatStateStacked frame;
            writeCString("(", ostr);
            window_definition->formatImpl(format_settings, state, frame);
            writeCString(")", ostr);
        }
    }
}
String ASTFunction::getID(char delim) const