> One way is to use the @class declaration to say that the > class will exist at run-time and the compiler doesn't have > to worry about the lack of a h

> One way is to use the @class declaration to say that the > class will exist at run-time and the compiler doesn't have > to worry about the lack of a header. Sure, you could just put "uses NSWindowController;" in your .m file and the compiler would know all about the NSWindowController class and its methods, but what about all the typedefs, defines, functions, and other bits C/C++ heritage that everyday Obj-C code uses? Obj-C has been around for 25+ years, and while the libraries have changed a lot during that time the language can still be implemented essentially as a preprocessor on top of a plain old C/C++ compiler, and I don't think that will ever change. Long live MacRuby, though. I look forward to the day that becomes an official first-class language for OS X development.