uint8_t can't be printed with cout

Question

I have a weird problem about working with integers in C++.

I wrote a simple program that sets a value to a variable and then prints it, but it is not working as expe

Answer 1

• Making use of ADL (Argument-dependent name lookup):

  #include 
  #include 
  #include 
  
  namespace numerical_chars {
  inline std::ostream &operator<<(std::ostream &os, char c) {
      return std::is_signed::value ? os << static_cast(c)
                                         : os << static_cast(c);
  }
  
  inline std::ostream &operator<<(std::ostream &os, signed char c) {
      return os << static_cast(c);
  }
  
  inline std::ostream &operator<<(std::ostream &os, unsigned char c) {
      return os << static_cast(c);
  }
  }
  
  int main() {
      using namespace std;
  
      uint8_t i = 42;
  
      {
          cout << i << endl;
      }
  
      {
          using namespace numerical_chars;
          cout << i << endl;
      }
  }
  

  output:

  *
  42
  

• A custom stream manipulator would also be possible.

• The unary plus operator is a neat idiom too (cout << +i << endl).