What do you think to change the funtion cPart to be a non void function? In this way the example could be more complete and demostrate how to call from ts -> js -> c++ -> c passing some arguments and back.

This is a really good suggestion thank you.
What do you think a phrase like this ? :

I'm a C function and I received this $argument from C++

And then return an int back ?

And the the c++ says:

I'm a C++ function and I received this $argument from JS and this $return from C

and the same for JS and TS ...

something like that ? looks cool 😄

Since I still learning I'll probably delay a little bit but eager to implement that

@NickNaso suggestions applied now it shows the following messages:

I'm a C function and I received 12 from C++ and I'm sending back 42 
I'm a C++ function I'm sending 12 to C and I received 42
I'm a Javascript function and I'm sending 11 to C++ and I received 42
I'm a TypeScript class constructor I'm sending 10 to JavaScript and I received 42

This is unnecessary, as it's already declared in root folder.

@gengjiawen thank you for the review, PR updated 👍