#include <iostream>
#include <sstream>
using namespace std;
 
class Log {
 public:
  Log() = default;
  Log(const Log&) = delete;
 
  ~Log() {
    cout << this << " dtor" << endl;
    cout << stream_.str() << endl;
  }
 
  template <class T>
  Log& operator<<(const T& info) {
    cout << this << " <<" << endl;
    stream_ << info;
    return *this;
  }
 
 private:
  stringstream stream_;
};
 
int main() {
	[]() -> Log&& {
	  Log log;
	  log << "A";
	  return move(log);
	} () << "B";
 
	return 0;
}

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