#include <memory>
#include <experimental/memory>
 
class Node {
public:
	int32_t x;
};
 
int main()
{
	{
		std::shared_ptr<Node> shared_node{std::make_shared<Node>()};
		std::weak_ptr<Node> weak_node{shared_node};
		// this ^ works
	}
 
	{
		std::unique_ptr<Node> unique_node{std::make_unique<Node>()};
		// but the following doesn't work :(
		// std::experimental::observer_ptr<Node> observer_node{unique_node};
		std::experimental::observer_ptr<Node> observer_node{std::experimental::observer_ptr<Node>(unique_node.get())};
		// any better way to do this ^ ?
	}
 
	return 0;
}

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