How to write `is_complete` template?

by

The answer given by Alexey Malistov can be used on MSVC with a minor modification:

namespace 
{
    template<class T, int discriminator>
    struct is_complete {  
      static T & getT();   
      static char (& pass(T))[2]; 
      static char pass(...);   
      static const bool value = sizeof(pass(getT()))==2;
    };
}
#define IS_COMPLETE(X) is_complete<X,__COUNTER__>::value

Unfortunately, the __COUNTER__ predefined macro is not part of the standard, so it would not work on every compiler.

More Related Contents:

  1. How to test whether class B is derived from template family of classes
  2. How does `is_base_of` work?
  3. What do compilers do with compile-time branching?
  4. Check if a variable type is iterable?
  5. Disambiguate overloaded member function pointer being passed as template parameter
  6. C++11 is_same type trait for templates
  7. How to tell if template type is an instance of a template class?
  8. Check if a type is passed in variadic template parameter pack
  9. How to tell if a type is an instance of a specific template class?
  10. Why do I get “unresolved external symbol” errors when using templates? [duplicate]
  11. Does C++ support compile-time counters?
  12. What does it mean to “ODR-use” something?
  13. C++ function template partial specialization?
  14. C++ invoke explicit template constructor
  15. constexpr if and static_assert
  16. How to achieve “virtual template function” in C++
  17. Deduce template argument from std::function call signature
  18. Difference between instantiation and specialization in c++ templates
  19. Select class constructor using enable_if
  20. Populate An Array Using Constexpr at Compile-time
  21. Why is it not possible to overload class templates?
  22. c++ template and header files [duplicate]
  23. Strong typedefs [duplicate]
  24. Lambda expressions as class template parameters
  25. mixing templates with polymorphism
  26. Default template parameter partial specialization
  27. std::remove_const with const references
  28. How to typedef a template class? [duplicate]
  29. if / else at compile time in C++?
  30. Conditional compilation based on template values?

Leave a Comment