ceph/src/boost/libs/hana/example/functional/flip.cpp

   1 // Copyright Louis Dionne 2013-2016
   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
   5 #include <boost/hana/assert.hpp>
   6 #include <boost/hana/config.hpp>
   7 #include <boost/hana/functional/flip.hpp>
   8 namespace hana = boost::hana;
   9
  10
  11 BOOST_HANA_CONSTEXPR_LAMBDA auto minus = [](int x, int y, int z = 0) {
  12     return x - y - z;
  13 };
  14
  15 int main() {
  16     BOOST_HANA_CONSTEXPR_CHECK(minus(3, 0) == 3 - 0);
  17     BOOST_HANA_CONSTEXPR_CHECK(hana::flip(minus)(3, 0) == 0 - 3);
  18
  19     BOOST_HANA_CONSTEXPR_CHECK(minus(3, 0, 1) == 3 - 0 - 1);
  20     BOOST_HANA_CONSTEXPR_CHECK(hana::flip(minus)(3, 0, 1) == 0 - 3 - 1);
  21 }