function-pointers

How can I compare two C++11 std::function s with operator== , and return true if both of said function s refer to the same function pointer? operator== for std::function compares a std::function with a null pointer, as far as I can tell the standard does not provide any details as to why. Although, this boost FAQ entry, Why can't I compare boost::function objects with operator== or operator!=? provides a rationale and as far as I can tell should be applicable to std::function as well. Quoting the FAQ: Comparison between boost::function objects cannot be implemented "well", and therefore will

Modern CPUs have extensive pipelining, that is, they are loading necessary instructions and data long before they actually execute the instruction. Sometimes, the data loaded into the pipeline gets invalidated, and the pipeline must be cleared and reloaded with new data. The time it takes to refill the pipeline can be considerable, and cause a performance slowdown. If I call a function pointer in C, is the pipeline smart enough to realize that the pointer in the pipeline is a function pointer, and that it should follow that pointer for the next instructions? Or will having a function pointer

I am having a pointer to the common static method class MyClass { private: static double ( *pfunction ) ( const Object *, const Object *); ... }; pointing to the static method class SomeClass { public: static double getA ( const Object *o1, const Object *o2); ... }; Initialization: double ( *MyClass::pfunction ) ( const Object *o1, const Object *o2 ) = &SomeClass::getA; I would like to convert this pointer to the static template function pointer: template <class T> static T ( *pfunction ) ( const Object <T> *, const Object <T> *); //Compile error where: class SomeClass { public: template

Sorry for the verbose introduction that follows. I need insight from someone knowing P/Invoke internals better than I do. Here is how I'm marshalling structures containing function pointers from C to C#. I would like to know whether it's the cleanest and/or most efficient way of doing it. I'm interfacing with a native DLL coded in C that provides the following entry point: void* getInterface(int id); You have to pass getInterface(int) one of the following enum values: enum INTERFACES { FOO, BAR }; Which returns a pointer to a structure containing function pointers like: typedef struct IFOO {

Here is the problem: 1) I have a class like so: class some_class { public: some_type some_value; int some_function(double *a, double *b, int c, int d, void *e); }; 2) Inside some_function , I use some_values from some_class object to get a result. 3) So, I have a concrete object and I want to get a pointer to this object some_function . Is it possible? I can't use some_fcn_ptr because the result of this function depends on the concrete some_value of an object. How can I get a pointer to some_function of an object? Thanks. typedef int (Some_class::*some_fcn_ptr)(double*, double*, int, int, void

Suppose I have these three functions: bool A(); bool B(); bool C(); How do I call one of these functions conditionally using a function pointer, and how do I declare the function pointer? Abhineet You can do the following: Suppose you have your A,B & C function as the following: bool A() { ..... } bool B() { ..... } bool C() { ..... } Now at some other function, say at main: int main() { bool (*choice) (); // now if there is if-else statement for making "choice" to // point at a particular function then proceed as following if ( x == 1 ) choice = A; else if ( x == 2 ) choice = B; else choice =