Using enable_if to match numbers

I want to use std::enable_if to make constructor that matches numbers. I tried the following code, but the constructor is not found. Main function has examples how I want to use this. What should I change to make this work?

#include <type_traits>
#include <string>

class A {
public:
    A(const std::wstring&, const std::wstring&)
    {}

    template<typename T>
    A(const std::wstring& n, typename std::enable_if<std::is_arithmetic<T>::value, T>::type v)
    {}
};

int main() {
    A(L"n", 1234); // does not compile
    A(L"n", 2.7); // does not compile
    A(L"n", L"n"); // compiles
    return 0;
}

Error on Ideone: template argument deduction/substitution failed