concat.cpp 1.7 KB

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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/concat.hpp>
  6. #include <boost/hana/equal.hpp>
  7. #include <boost/hana/optional.hpp>
  8. #include <laws/base.hpp>
  9. namespace hana = boost::hana;
  10. using hana::test::ct_eq;
  11. int main() {
  12. auto rv_nothing = [] { return hana::nothing; }; // rvalue nothing
  13. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  14. hana::concat(rv_nothing(), hana::nothing),
  15. hana::nothing
  16. ));
  17. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  18. hana::concat(hana::nothing, rv_nothing()),
  19. hana::nothing
  20. ));
  21. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  22. hana::concat(rv_nothing(), rv_nothing()),
  23. hana::nothing
  24. ));
  25. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  26. hana::concat(rv_nothing(), hana::just(ct_eq<0>{})),
  27. hana::just(ct_eq<0>{})
  28. ));
  29. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  30. hana::concat(hana::just(ct_eq<0>{}), rv_nothing()),
  31. hana::just(ct_eq<0>{})
  32. ));
  33. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  34. hana::concat(hana::nothing, hana::nothing),
  35. hana::nothing
  36. ));
  37. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  38. hana::concat(hana::nothing, hana::just(ct_eq<0>{})),
  39. hana::just(ct_eq<0>{})
  40. ));
  41. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  42. hana::concat(hana::just(ct_eq<0>{}), hana::nothing),
  43. hana::just(ct_eq<0>{})
  44. ));
  45. BOOST_HANA_CONSTANT_CHECK(hana::equal(
  46. hana::concat(hana::just(ct_eq<0>{}), hana::just(ct_eq<1>{})),
  47. hana::just(ct_eq<0>{})
  48. ));
  49. }