c++ - How do I strongly typedef non-primitive types? -


Considering the following program in which one function accepts both type of expected type and type of typingfif type is. 

  // A user defined type class widget {}; // A function that creates a widget zero function (widget w) {} int main () {// Type (it is C ++ 11 syntax for typingfifth. This is the same thing) Gadget = Using Widget ; // Make two "different types" (well .. they are not really different as you will see) widget w; Gadgets; // Call a function which should only accept the widget function (w); // work (good) work (g); // & amp; Lt; - Works (I do not want to compile this)} As you can see, a type-tof actually does not separate a new type. I thought to inherit the type instead:  
  // Instead of the class gadget heir: public widget {}; // two "different types" widget w; Gadgets; // should call the function which should only accept the widget function (w); // work (good) work (g); // & lt; - Works (I do not want this to be compiled)   
 There is only one problem. Paying attention to promotion, I tried a strong typedef:  
  #include & lt; Boost / serialization / strong_typedef.hpp & gt; // A user defined type class widget {}; // a function that defines the user defined type zero function (w) {} int main () {// strongly typedef BOOST_STRONG_TYPEDEF (widget, gadget) // two "different type" widget w; Gadgets; // should call the function which should only accept the widget function (w); Ceremony (g); }   
  Compiled Errors:   
  in the member function: ??? bool main () :: Gadget :: Operator == (const (main) :: Gadget and;) Context: Error: There is no match for any operator == A ???? (Operand types are - Cant Widget and Content Widget). BOOST_STRONG_TYPEDEF (widget, gadget) ^ Member Function in-bool main () :: Gadget :: Operator & lt; (const Main () :: Gadget & amp;) Context: Error: There is no match for any operator & lt;? (Operand types are- Cunts Widget and 'Cunts Widget).) BOOST_STRONG_TYPEDEF (Widget, Gadget) ^   
 Apparently BOOST_STRONG_TYPEDEF only works on primitive types. 
 I tried to inherit again, but to stop the underlying conversion:  
  // I want functionality, but these are not the same type! Class Gadget: Public Widget {Operator Widget () = Delete; };   
 This does not work either.  
  Question:   
     
  1.  Why strong_prothic only promotes primitive type?  
  2.  Can I type a non-primitive type to gain robust functionality to promote strong typography? Actually you need two unrelated classes with the same behavior. I would use a parametrized template for it:  
      template & lt; int tag & gt; Class widgetgate {...}; Type widget widget & lt; 0 & gt; Widget; Type widget widget & lt; 1 & gt; Gadget;

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