Pointers — you either love them, or you haven’t fully understood them yet. But before you storm off to the comment section now, pointers are indeed a polarizing subject and are both C&#… ...

The array mOutpuDevices is declared to contain pointers to the PinOutputAbstract class, the parent. But the array elements are pointers to instances of child classes.

IIRC C++ does not allow methods to be passed as function pointers. if b () were outside a class (a global function) it could be passed safely. Static methods might also be callable, but I'm not sure.