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  1. #include <functional>
  2. #include <iostream>
  3.  
  4. void check(const std::function<void()>& f)
  5. {
  6. 	std::cout << ((f) ? "NOT empty" : "empty") << std::endl;
  7. }
  8.  
  9. int main()
  10. {
  11. 	std::function<void()> f;
  12. 	check(f);
  13.  
  14. 	f = []{};
  15. 	check(f);
  16.  
  17. 	return 0;
  18. }
Success #stdin #stdout 0.01s 5320KB
comments (?)
stdin
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Standard input is empty
stdout
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empty
NOT empty
https://ideone.com/QvcyD6
language:
C++14 (gcc 8.3)
created:
15 hours ago
visibility:
public

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