Compiler error when comparing two typeid expressions for equality -


on code comes training video:

#include <iostream>  template<typename t> struct mystruct {    t data; };  int main(void) {    mystruct<int> s;    s.data = 2;    assert(typeid(s.data) == typeid(int)); }

i compiler error:

class_templates.cpp:12:26: error: invalid operands binary expression ('const std::type_info' , 'const std::type_info')    assert(typeid(s.data) == typeid(int));           ~~~~~~~~~~~~~~ ^  ~~~~~~~~~~~

compiled with:

clang++ -std=c++14 class_templates.cpp

edit: had compiled g++ have gotten better error:

class_templates.cpp:14:20: error: must #include <typeinfo> before using typeid     assert(typeid(s.data) == typeid(int));

you must use #include <typeinfo> in order use typeid(), otherwise program ill-formed.

also see:

why need #include <typeinfo> when using typeid operator?


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