ceph/src/boost/libs/hana/example/map/searchable.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/at_key.hpp>
   7 #include <boost/hana/equal.hpp>
   8 #include <boost/hana/find.hpp>
   9 #include <boost/hana/integral_constant.hpp>
  10 #include <boost/hana/map.hpp>
  11 #include <boost/hana/optional.hpp>
  12 #include <boost/hana/pair.hpp>
  13 #include <boost/hana/type.hpp>
  14 namespace hana = boost::hana;
  15
  16
  17 constexpr auto m = hana::make_map(
  18     hana::make_pair(hana::type_c<int>, 'i'),
  19     hana::make_pair(hana::type_c<float>, 'f')
  20 );
  21 static_assert(hana::find(m, hana::type_c<int>) == hana::just('i'), "");
  22 static_assert(hana::find(m, hana::type_c<float>) == hana::just('f'), "");
  23 BOOST_HANA_CONSTANT_CHECK(hana::find(m, hana::type_c<void>) == hana::nothing);
  24 BOOST_HANA_CONSTANT_CHECK(hana::find(m, hana::int_c<3>) == hana::nothing);
  25
  26 // operator[] is equivalent to at_key
  27 static_assert(m[hana::type_c<int>] == 'i', "");
  28 static_assert(m[hana::type_c<float>] == 'f', "");
  29
  30 int main() { }