Fix classes inside functions

[FetBoba]

Wasm backend crashes when classes defined in an outer scope are referenced inside nested functions (field access and class pattern matching). Fix: implemented lazy/on-demand creation/registration of top-level class struct types during lowering so the needed wasm type exists at each use site.

[Derppening]

Could you please add a description of what this specifically fixes and how you fixed the problem?

[LPTK]

Please merge with upstream and address @Derppening's comment.

[FetBoba]

Could you please add a description of what this specifically fixes and how you fixed the problem?

Ok. I added it to description of this pr.

[LPTK]

Wasm backend crashes when classes defined in an outer scope are referenced inside nested functions (field access and class pattern matching). Fix: implemented lazy/on-demand creation/registration of top-level class struct types during lowering so the needed wasm type exists at each use site.

Why would we need this? It seems to me that you should just make one pass to register all the types of the program, and then a separate pass to generate the code of functions.

[FetBoba]

Why would we need this? It seems to me that you should just make one pass to register all the types of the program, and then a separate pass to generate the code of functions.

I thought that there might be some complications with correct order of registering types.

I will try to implement preregistering of all types. Also, by all types you mean top-level classes? Can you clarify this?

[LPTK]

Also, by all types you mean top-level classes? Can you clarify this?

Yes. Not sure what else you think I could mean.

[Derppening]

Most of the changes look good, please address the following comments.

Please also all brief documentation for new private functions.