From my experience from C/C++ domains, it would be very useful for a system programing language to be able to compile different codes based on different conditions.
I already know in Rust we got Attributes, attributes like windows_subsystem
can enable/disable code fragments based on current OS.
What I still can not figure out is, custom situation, like for example in C/C++:
#if ENABLE_VIDEO
// ... code for video only
#endif
How can I achive similar in Rust?