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#include <iostream>
#include <utility>
#include <typeinfo>
using namespace std;
 
class Bar {
	public:
		Bar() { value = 5; }
 
		Bar(Bar&& other) {
			value = std::move(other.value);
			other.value = int();
		}
 
		int value;
};
 
void foo(Bar&& bar) {
	Bar test1(bar); 				// this doesnt work !!!
	Bar test2(std::move(bar)); 		// this does work
	Bar test3((Bar&&)bar);			//and this works too!
 
	// yet this returns true:
	bool sameTypes1 = typeid(bar) == typeid(Bar&&);
	bool sameTypes2 = typeid(bar) == typeid(std::move(bar));
 
	std::cout << sameTypes1 << std::endl; // true or 1
    std::cout << sameTypes2 << std::endl; // true or 1
}
 
int main() {
	Bar bar;
 
	foo(std::move(bar));
 
	return 0;
}

prog.cpp: In function ‘void foo(Bar&&)’:
prog.cpp:19:15: error: use of deleted function ‘constexpr Bar::Bar(const Bar&)’
  Bar test1(bar);     // this doesnt work !!!
               ^
prog.cpp:6:7: note: ‘constexpr Bar::Bar(const Bar&)’ is implicitly declared as deleted because ‘Bar’ declares a move constructor or move assignment operator
 class Bar {
       ^

Standard output is empty