Hello, Nim community!
I'm working on macros which allows usage of C++ libraries from C backend with
minimal effort. During reflection on the idea I've encountered some questions:
* Is there a way to determine which backend is used to compile current file?
It's necessary for constructions like:
```nim
when isCppBackend:
... # use typical importcpp pragma
when isJSBackend:
... # error message
when isCBackend:
... # use some magic to represent C++ objects in C terms
```
* Is there a way to obtain Nim or C++ compiler command used at compile time?
The idea is to call C++ or Nim (with C++ backend) compiler and run "spy code"
to determine class field offsets, mangled names (for fast and unsafe calls) and
other C++ specific things.
The part of the idea realization (without C backend support) can be found
`here<https://github.com/xomachine/wraptool-cpp2nim>`_
