In many cases, it is necessary to define subgroups... For example If I have some sub-system that  contains a number of functions.. In C++ I could create the sub-system as a class and in the class I write the function. The main goal is to have syntax that looks elegant, and understandable like this: subsystem.function1()   But in Autoit we can't use the dot as a mark to display this logic  structure.   In Autoit all I can do is create file named subsystem.au3 an