Passing a string literal as a type argument to a class template

Question

I want to declare a class template in which one of the template parameters takes a string literal, e.g. my_class<"string">.

Can anyone give me some compilable code which declares a simple class template as described?

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Note: The previous wording of this question was rather ambiguous as to what the asker was actually trying to accomplish, and should probably have been closed as insufficiently clear. However, since then this question became multiple times referred-to as the canonical ‘string literal type parameter’ question. As such, it has been re-worded to agree with that premise.

Answer 1

You can have a const char* non-type template parameter, and pass it a const char[] variable with static linkage, which is not all that far from passing a string literal directly.

#include <iostream>      template<const char *str>  struct cts {     void p() {std::cout << str;} };  static const char teststr[] = "Hello world!"; int main() {     cts<teststr> o;     o.p(); } 

http://coliru.stacked-crooked.com/a/64cd254136dd0272

Answer 2

Further from Neil's answer: one way to using strings with templates as you want is to define a traits class and define the string as a trait of the type.

#include <iostream>  template <class T> struct MyTypeTraits {    static const char* name; };  template <class T> const char* MyTypeTraits<T>::name = "Hello";  template <> struct MyTypeTraits<int> {    static const char* name; };  const char* MyTypeTraits<int>::name = "Hello int";  template <class T> class MyTemplateClass {     public:      void print() {          std::cout << "My name is: " << MyTypeTraits<T>::name << std::endl;      } };  int main() {      MyTemplateClass<int>().print();      MyTemplateClass<char>().print(); } 

prints

My name is: Hello int My name is: Hello