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I'd like to have a variadic template function inside a class. The variadic template arguments are chars which should be processed in a loop-like manner. So I thought of writing it like in haskell with head/tail splitting the list until a base case (empty list) is reached. As an example, let's just count the number of arguments given (only a minimal example). I came up with the following code: struct MyClass { template<char ...X> static int count(); }; template<> int MyClass::count<>() { return 0; } template<char Head, char ...Tail> int MyClass::count<Head, Tail...>() { return 1 + count<Tail...>(); } However, this doesn't seem to work : prog.cpp:12:35: error: function template partial specialization ‘count<Head, Tail ...>’ is not allowed prog.cpp:12:5: error: prototype for ‘int MyClass::count()’ does not match any in class ‘MyClass’ prog.cpp:3:16: error: candidate is: template<char ...X> static int MyClass::count() How can I achieve this? I know that partial specialization isn't supported for functions. But I thought that specializing a variadic template into head/tail and empty base case version isn't a partial specialization but a full specialization, but maybe I'm wrong? Do I need to write this as a class instead of a function? I found examples (printf) which implement a base case without using the template syntax at all. But I guess that my case is different, since the call for printf doesn't use template syntax but type deduction , so printf(tail...) calls printf() if tail is empty. On the other side, in my case, when calling the base case, count<>() isn't the same as count() .

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