indeed:
Well if that's just the "idea" how can we know what is actually happening? Because that specific example (correct me if I'm wrong) wouldn't work at all. See here:
http://arduino.cc/en/Hacking/LibraryTutorial
It is a lot different from defining a function in-sketch.
Yes sorry I forgot to add the declaration of my function into the .h file, but I did it in my code. Moreover the function is a method for a class.