How to add a constructor with pointer to function as a parameter

Question

I have this following struct (in the header file):

struct StateTransitions {
    State currentState;
    State nextState;
    void (*fn)();

    StateTransitions (State currentState, State nextState, void (*fn)())
    {

    }
};

And I am trying to push some instances of this struct into a vector (inside .cpp file):

void MyClass::Start()
{

}

transitions.push_back(StateTransitions(Low, Started, &MyClass::Start));

I cannot get this to compile. I am not sure if my declaration of the constructor inside the class is correct.

What is the correct way to add a constructor so I can't add this type of objects to my vector ?

I am using pre-C++11.

Function pointer and member function pointer are different. You might want `void (MyClass::*)()`. — songyuanyao, Aug 26 '16 at 06:18
@songyuanyao: you are right, I got confused. This seems to build now. — Adrian, Aug 26 '16 at 06:21

score 2 · Accepted Answer · edited May 23 '17 at 12:01

2

You cannot pass a pointer to a member function as a static function. The reason is that a member function needs something to be passed to the this pointer, while a static function does not (and the compiler needs to check the type of whatever you are passing as this).

See also: Function pointer to member function

edited May 23 '17 at 12:01

Community

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answered Aug 26 '16 at 06:21

szym

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How to add a constructor with pointer to function as a parameter

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