c++ - Is there a type trait to count the total number of constructors? -

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is possible deduce number of constructors type has during compile time? 

#include <iostream> #include <type_traits>  struct a{      int m_i;     float m_f      //constructor 1     a(int i): m_i(i) {}      //constructor 2     a(float f): m_f(f) {}  };  int main() {      //prints 2     std::cout << number_of_constructors<a>::value << '\n'; }

i hoping avoid macro involvement constructors, perhaps way.

is possible deduce number of constructors type has during compile time?

in c++11/14? no, far can tell.

why? because c++ don't have support reflections, there study group sg7: reflection work on proposal add reflection c++.


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