> Is it just about convenience so you don't need to bother with putting your C++ code in a different file?
Yes, mostly.
I find that having the code in place makes a big difference. I do not like useless levels of indirection and context switches while coding. This way is much better then having to edit three files (the .cpp, the ffi module, and the caller) each time I want to do a call into C++ while making sure they are in sync.
> Is it just about convenience so you don't need to bother with putting your C++ code in a different file?
Yes, mostly. I find that having the code in place makes a big difference. I do not like useless levels of indirection and context switches while coding. This way is much better then having to edit three files (the .cpp, the ffi module, and the caller) each time I want to do a call into C++ while making sure they are in sync.