is_empty.cpp 961 B

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  1. // Copyright Louis Dionne 2013-2017
  2. // Distributed under the Boost Software License, Version 1.0.
  3. // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
  4. #include <boost/hana/assert.hpp>
  5. #include <boost/hana/experimental/types.hpp>
  6. #include <boost/hana/is_empty.hpp>
  7. #include <boost/hana/not.hpp>
  8. namespace hana = boost::hana;
  9. template <int> struct x;
  10. int main() {
  11. BOOST_HANA_CONSTANT_CHECK(hana::is_empty(
  12. hana::experimental::types<>{}
  13. ));
  14. BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(
  15. hana::experimental::types<x<0>>{}
  16. )));
  17. BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(
  18. hana::experimental::types<x<0>, x<1>>{}
  19. )));
  20. BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(
  21. hana::experimental::types<x<0>, x<1>, x<2>>{}
  22. )));
  23. BOOST_HANA_CONSTANT_CHECK(hana::not_(hana::is_empty(
  24. hana::experimental::types<x<0>, x<1>, x<2>, x<3>>{}
  25. )));
  26. }