title: const member functions can call const member functions only?
body: <p>Do const member functions call only const member functions?</p>
  
  <pre><code>class Transmitter{
    const static string msg;
    mutable int size;
    public: 
      void xmit() const{
      size = compute();
      cout&lt;&lt;msg;
    }
    private:
     int compute() const{return 5;}
  };
  
   string const Transmitter::msg = "beep";
  
   int main(){
     Transmitter t;
     t.xmit();
     return EXIT_SUCCESS;
   }
  </code></pre>
  
  <p>If i dont make compute() a const, then the compiler complains.
  Is it because since a const member function is not allowed to modify members, it wont allow
  any calls to non-consts since it would mean that the const member function would be 'indirectly' modifying the data members?</p>