ceph/src/boost/libs/hana/test/optional/chain.cpp

   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
   5 #include <boost/hana/assert.hpp>
   6 #include <boost/hana/chain.hpp>
   7 #include <boost/hana/equal.hpp>
   8 #include <boost/hana/optional.hpp>
   9
  10 #include <laws/base.hpp>
  11 namespace hana = boost::hana;
  12 using hana::test::ct_eq;
  13
  14
  15 int main() {
  16     auto f = [](auto x) {
  17         return hana::just(hana::test::_injection<0>{}(x));
  18     };
  19
  20     BOOST_HANA_CONSTANT_CHECK(hana::equal(
  21         hana::chain(hana::just(ct_eq<3>{}), f),
  22         f(ct_eq<3>{})
  23     ));
  24
  25     BOOST_HANA_CONSTANT_CHECK(hana::equal(
  26         hana::chain(hana::nothing, f),
  27         hana::nothing
  28     ));
  29
  30     // test with operators
  31     BOOST_HANA_CONSTANT_CHECK(hana::equal(
  32         hana::just(ct_eq<3>{}) | f,
  33         f(ct_eq<3>{})
  34     ));
  35
  36     BOOST_HANA_CONSTANT_CHECK(hana::equal(
  37         hana::nothing | f,
  38         hana::nothing
  39     ));
  40 }