text: #include <string>
  #include <functional>
  
  const std::function<std::string(const char*)> G_TRANSLATION_FUN;
  
  int main(int argc, char** argv)
  {
     const char* input = "Hello, world!";
     std::string output = G_TRANSLATION_FUN(input);
     if (output != input)
        exit(1);
     exit(0);
  }