This directive is a small hack that can be used when writing macros. Because macros do not have normally scoping, it can be difficult to reference something that is defined in the same package as the macro, since when the macro is expanded it might not be visible.

#this_package is used to represent the current file's package as a object in which you can look things up.

internal_details :: (x: rawptr, T: type_expr) {
	// ...

useful_macro :: macro (x: & $T) {
	#this_package.internal_details(x, T);

This pattern is very common in the core libraries of Onyx, where you have a macro that takes a pointer to anything, but it gets expanded to a procedure call that simply passes the pointer and the type of the value.

This has to use #this_package because internal_details is not going to be directly accessible when the macro is expanded. But by specifying that it needs to be looked up in the current package, this problem can be avoided.