模糊的模板实例化

Question

有人能解释一下这里的含糊之处吗？

template <typename...> struct thing;

template <typename... Rest>
struct thing<int&, Rest&...> {
    thing(int&, Rest&...) { }
};

template <typename First, typename... Rest>
struct thing<First&, Rest&...> {
    thing(First&, Rest&...) { }
};

int main() {
    int myint;
    char mychar;
    thing<int&, char&> t(myint, mychar);
}

Answer 1

如果你专注于int而不是int&它有效

template <typename...> struct thing;

template <typename... Rest>
struct thing<int, Rest...> {
    thing(int&, Rest&...) { }
};

template <typename First, typename... Rest>
struct thing<First, Rest...> {
    thing(First&, Rest&...) { }
};