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copied!<p>You need another template parameter, because you care about two different classes - the type of the pointer (and hence the member function you're going to call with it), and the type of the container:</p> <pre><code>#include <list> struct AirplaneType { }; struct Airplane : AirplaneType { int check() const { return 3; } }; template <typename T, typename U, typename I> void add(T* element, std::list<U*> & container, I (T::*f)() const) { container.push_back(element); I i = (element->*f)(); } int main() { std::list<AirplaneType*> ls; Airplane a; add(&a, ls, &Airplane::check); } </code></pre> <p>In this case my <code>add</code> function doesn't really use the fact that <code>container</code> is a <code>list</code>, so a more sensible version might be:</p> <pre><code>template <typename T, typename U, typename I> void add(T* element, U & container, I (T::*f)() const) { container.push_back(element); I i = (element->*f)(); } </code></pre> <p>And then again, you could abstract further:</p> <pre><code>template <typename T, typename U, typename AUF> void add(T element, U & container, AUF func) { container.push_back(element); typename AUF::result_type i = func(element); } </code></pre> <p>... but that's slightly less convenient for the caller:</p> <pre><code>#include <functional> add(&a, ls, std::mem_fun(&Airplane::check)); </code></pre> <p><i>Any suggestions for good practice?</i></p> <p>Don't create containers of raw pointers.</p> <p>Edit: to get this working with a virtual function, with each of my options:</p> <pre><code>#include <list> #include <functional> #include <iostream> struct AirplaneType { virtual int check() const { return 0; } }; struct Airplane : AirplaneType { int check() const { std::cout << "check\n"; return 3; } }; template <typename T, typename U, typename I> void add(U* element, std::list<T*> & container, I (U::*f)() const) { container.push_back(element); I i = (element->*f)(); } template <typename T, typename U, typename AUF> void add2(T element, U & container, AUF func) { container.push_back(element); typename AUF::result_type i = func(element); } int main() { std::list<AirplaneType*> ls; Airplane a; add(static_cast<AirplaneType*>(&a), ls, &AirplaneType::check); add2(&a, ls, std::mem_fun(&AirplaneType::check)); } </code></pre> <p>Output is:</p> <pre><code>check check </code></pre> <p>which shows that the override is correctly called even though the function pointer was taken to <code>AirplaneType::check</code>, not <code>Airplane::check</code>.</p>

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