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There is a technique I sometimes use when overriding template functions that goes like this: #include <utility> template<int> struct unique_enum { enum class type {}; }; template<int index> using UniqueEnum = typename unique_enum<index>::type; template<bool b, int index=1> using EnableFuncIf = typename std::enable_if< b, UniqueEnum<index> >::type; template<bool b, int index=1> using DisableFuncIf = EnableFuncIf<!b, -index>; // boring traits class: template<typename T> struct is_int : std::false_type {}; template<> struct is_int<int> : std::true_type {}; #include <iostream> // use empty variardic packs to give these two SFINAE functions different signatures: template<typename C, EnableFuncIf< is_int<C>::value >...> void do_stuff() { std::cout << "int!\n"; } template<typename C, DisableFuncIf< is_int<C>::value >...> void do_stuff() { std::cout << "not int!\n"; } int main() { do_stuff<int>(); do_stuff<double>(); } This distinguishes do_stuff from do_stuff , because one takes 0 or more UniqueEnum<1> s, and the other takes 0 or more UniqueEnum<-1> s. gcc 4.8 considers these different empty packs to be distinct. However, in the latest version of clang I tried, this fails: it treats the function with 0 UniqueEnum<1> s as being the same as the function with 0 UniqueEnum<-1> s. There are easy workarounds that work in clang, but I'm wondering if my above technique is legal -- do two function template s, which differ only by empty variardic parameter packs, actually different?

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