c++ - std::is_same<A,B>::value == true in line 1, false in line 2 -


i have code returns true in 1 line, false in other.

for example, 

struct z{     static const int value = 10; };  struct : z{ }; struct b : z{ };  int main(){     if(std::is_same<a,b>::value){         static_assert(std::is_same<a,b>::value , "why here?");     }     return 0; }

can please explain why throws static assert error?

this because static_assert static (that is: compile time) assert. not care if statement (evaluated @ run-time) above.


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