ceph/src/boost/libs/hana/example/find.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/find.hpp>
   8 #include <boost/hana/integral_constant.hpp>
   9 #include <boost/hana/map.hpp>
  10 #include <boost/hana/optional.hpp>
  11 #include <boost/hana/pair.hpp>
  12 #include <boost/hana/tuple.hpp>
  13 #include <boost/hana/type.hpp>
  14 namespace hana = boost::hana;
  15
  16
  17 BOOST_HANA_CONSTANT_CHECK(
  18     hana::find(hana::make_tuple(hana::int_c<1>, hana::type_c<int>, '3'), hana::type_c<int>) == hana::just(hana::type_c<int>)
  19 );
  20 BOOST_HANA_CONSTANT_CHECK(
  21     hana::find(hana::make_tuple(hana::int_c<1>, hana::type_c<int>, '3'), hana::type_c<void>) == hana::nothing
  22 );
  23
  24 constexpr auto m = hana::make_map(
  25     hana::make_pair(hana::int_c<2>, 2),
  26     hana::make_pair(hana::type_c<float>, 3.3),
  27     hana::make_pair(hana::type_c<char>, hana::type_c<int>)
  28 );
  29 static_assert(hana::find(m, hana::type_c<float>) == hana::just(3.3), "");
  30
  31 int main() { }