c++ - C++ macro and template with multiple arguments error

Question

I have this simple (useless) code to demonstrate the problem:

template<typename _Tx, typename _Ty>
struct foo{};

#define TO_STRING(Type) #Type

int main()
{
    std::string sInt = TO_STRING(int);
    std::string sfoo1 = TO_STRING(foo<int, float>); //warning and unexpected value - "foo<int"
    std::string sfoo2 = TO_STRING((foo<int, float>)); //no warning, still unexpected value "(foo<int, float>)"
}

Is there a way to pass templates with multiple arguments to macros without using () ?

Answer 1

这可能并不理想，但我认为它几乎可以在任何编译器上工作（如果你找到一个不适合的编译器，很容易在不改变接口的情况下变笨）：

#define TO_STRING1(_a_) #_a_
#define TO_STRING2(_a_, ...) #_a_ ", " TO_STRING1(__VA_ARGS__)
#define TO_STRING3(_a_, ...) #_a_ ", " TO_STRING2(__VA_ARGS__)
#define TO_STRING4(_a_, ...) #_a_ ", " TO_STRING3(__VA_ARGS__)

唯一的缺点是您必须自己计算逗号，例如：

std::string sInt = TO_STRING1(int);
std::string sfoo = TO_STRING2(foo<int, float>);