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Suppose I want to write a generic function void f<T>() , which does one thing if T is a POD type and another thing if T is non-POD (or any other arbitrary predicate). One way to achieve this would be to use a tag-dispatch pattern like the standard library does with iterator categories: template <bool> struct podness {}; typedef podness<true> pod_tag; typedef podness<false> non_pod_tag; template <typename T> void f2(T, pod_tag) { /* POD */ } template <typename T> void f2(T, non_pod_tag) { /* non-POD */ } template <typename T> void f(T x) { // Dispatch to f2 based on tag. f2(x, podness<std::is_pod<T>::value>()); } An alternative would be to use static member function of partially specialised types: template <typename T, bool> struct f2; template <typename T> struct f2<T, true> { static void f(T) { /* POD */ } }; template <typename T> struct f2<T, false> { static void f(T) { /* non-POD */ } }; template <typename T> void f(T x) { // Select the correct partially specialised type. f2<T, std::is_pod<T>::value>::f(x); } What are the pros and cons of using one method over the other? Which would you recommend?

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