C++: error “explicit specialization in non-namespace scope”

Question

template
class Bimap {
public:
    class Data {
    private:
        template Data& set(T);
        template<>         


        

Answer 1

One way forget templates, overload:

Data& set(T1 v) { /*...*/ }

but here is a trick which I use sometimes

you can specialize class template within class:

class {
    template
    struct function_ {
        static void apply(T);
    };

    template<>
    struct function_ {
        ...
    };

    template
    void function(T t) { return function_::apply(t); }