Function Pointers
Try this and see if it does you any good: :)
Character.h
Character.cpp
Character.h
#define CALL_MEMBER_FUNC(object,ptrToMember) ((object).*(ptrToMember))()class Character{ public: Character(void); ~Character(void); void Sleep(); // All the other funcitons private: void (Character::*pDecisionFunciton)();};Character.cpp
pDecisionFunciton = &Character::Sleep; CALL_MEMBER_FUNC(*this, pDecisionFunciton);
Quote:Original post by Shadow WolfNo need for macros:
Try this and see if it does you any good: :)
Character.h
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Character.cpp
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template < typename T >void CallMemberFunction(T& object, void (T::*function)()){ ((object).*(function))();}// ...pDecisionFunction = &Character::Sleep; CallMemberFunction(*this, pDecisionFunction);
Author
Quote:Original post by Shadow Wolf
Try this and see if it does you any good: :)
Character.h
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Character.cpp
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It compiles fine now, but It doesnt actually call the function its pointing to. So i guess this is a problem with the macro? Can anyone help here?
Quote:It compiles fine now, but It doesnt actually call the function its pointing to. So i guess this is a problem with the macro? Can anyone help here?It should work (although, again, I wouldn't recommend using a macro).
How do you know the function isn't being called? Can you post your code?
Author
Sorry it was my mistake.
I'd missed the brackets at the end of the macro.
Thanks for all your help.
I'd missed the brackets at the end of the macro.
Thanks for all your help.
#define CALL_MEMBER_FUNC(object,ptrToMember) ((object).*(ptrToMember)) template < typename T >void CallMemberFunction(T& object, void (T::*function)()){ ((object).*(function))();}I'm not entirely convinced either of those has any purpose, seeing that they both make you type more to achieve something relatively simple, and the syntax for calling member function through the pointer is unmistakeable for anything else because of the special .* operator.
If it is for inexperience programmers that may not be familiar with the syntax, one could show that to them, and if they don't get it they should be prohibited from using pointers to methods.
Besides, wouldn't you need a whole set of overloads in case the method takes any parameters?
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Or perhaps these are for providing a simple function-call like syntax (for who knows which templated use). But then shouldn't these be a struct with the () operator and doesn't std::mem_fun_ref already do this (and boost::mem_fn even better)?
Quote:Original post by visitorMy intent was mainly to demonstrate that there's no reason to use macros for this. To be sure, the shortcut is of limited usefulness, and is made largely irrelevant by the tools that you mentioned (boost::function, boost::bind, etc.).
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I'm not entirely convinced either of those has any purpose, seeing that they both make you type more to achieve something relatively simple, and the syntax for calling member function through the pointer is unmistakeable for anything else because of the special .* operator.
If it is for inexperience programmers that may not be familiar with the syntax, one could show that to them, and if they don't get it they should be prohibited from using pointers to methods.
Besides, wouldn't you need a whole set of overloads in case the method takes any parameters?
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Or perhaps these are for providing a simple function-call like syntax (for who knows which templated use). But then shouldn't these be a struct with the () operator and doesn't std::mem_fun_ref already do this (and boost::mem_fn even better)?
I don't know that such a convenience function would be *completely* pointless in all situations, but honestly I don't feel strongly enough about it to try and make a case for it :) Really, the goal was just to demonstrate to the OP how to do it without using macros if, for whatever reason, the OP does want to use a shortcut of this sort.
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