Wait, none of this makes sense.
Huh? How does this happen? Adding python/include also causes parser-inc to be added? Why? That doesn’t make any sense at all. These are two different directories, and nothing in Python knows anything at all about interrogate’s parser-inc directory. Anyway, there’s no way that including another file can cause parser-inc to be added to the include path, unless you’re suggesting there’s a weird bug in Visual Studio.
HAVE_PYTHON is a symbol defined within dtool_config.h to tell the Panda code whether it is being built against Python or not. It’s important not to mess with it. It should be defined when you are compiling with the Python interfaces, as it appears that you are. However, all this does is cause additional Python symbols to be included and additional Python interfaces to be compiled; it does not add parser-inc to the include path.
I think there must be a parser-inc somewhere in your project specifications that you’re not aware of. I can’t think of any other way it could be getting onto the include path.
David