Thread: macros: can i test if a function was defined?

can i test if a function was defined for i see what function to use?
if i call a not defined function, i will get 2 compilers errors. so for resolve the problem, i must use macros.
i'm trying do some code but without success

Code:

#ifdef clsPointer->MouseClick            
                 clsPointer->MouseClick();
        #else
            MouseClick();
        #endif

these code isn't completed, but for show what i mean.
if i define the clsPointer->MouseClick, the compiler must use the clsPointer->MouseClick, but if sin't, the compiler must use MouseClick.
so what i miss on these code?