and to study source code commented in Mandarin Chinese.
Awesome

Yes, member functions are meant with classes. It should have been implemented already, but, as it sometimes happens when improving other people's software, it turned out to be more complicated than expected. Therefore I can't give a release date at the moment. - The subfolder won't be necessary because the temporary files won't be used anymore in future map compiler versions.
Both things are very nice to hear, I hope they arrive soon.