ceph/src/boost/libs/hana/example/optional/value.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/equal.hpp>
   7 #include <boost/hana/optional.hpp>
   8 #include <boost/hana/type.hpp>
   9
  10 #include <string>
  11 namespace hana = boost::hana;
  12
  13
  14 int main() {
  15     static_assert(hana::just('x').value() == 'x', "");
  16     BOOST_HANA_CONSTANT_CHECK(*hana::just(hana::type_c<int>) == hana::type_c<int>);
  17     BOOST_HANA_RUNTIME_CHECK(hana::just(std::string{"abcd"})->size() == 4);
  18
  19     // hana::nothing.value(); // compile-time error
  20 }