ceph/src/boost/libs/hana/test/integral_constant/times.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/core/is_a.hpp>
   7 #include <boost/hana/integral_constant.hpp>
   8 #include <boost/hana/value.hpp>
   9 namespace hana = boost::hana;
  10
  11
  12 void function() { }
  13 void function_index(...) { }
  14
  15 int main() {
  16     // times member function
  17     {
  18         int counter = 0;
  19         hana::int_c<3>.times([&] { ++counter; });
  20         BOOST_HANA_RUNTIME_CHECK(counter == 3);
  21
  22         // Call .times with a normal function used to fail.
  23         hana::int_c<3>.times(function);
  24
  25         // make sure times can be accessed as a static member function too
  26         decltype(hana::int_c<5>)::times([]{ });
  27
  28         // make sure xxx.times can be used as a function object
  29         auto z = hana::int_c<5>.times;
  30         (void)z;
  31     }
  32
  33     // times.with_index
  34     {
  35         int index = 0;
  36         hana::int_c<3>.times.with_index([&](auto i) {
  37             static_assert(hana::is_an<hana::integral_constant_tag<int>>(i), "");
  38             BOOST_HANA_RUNTIME_CHECK(hana::value(i) == index);
  39             ++index;
  40         });
  41
  42         // Calling .times.with_index with a normal function used to fail.
  43         hana::int_c<3>.times.with_index(function_index);
  44
  45         // make sure times.with_index can be accessed as a static member
  46         // function too
  47         auto times = hana::int_c<5>.times;
  48         decltype(times)::with_index([](auto) { });
  49
  50         // make sure xxx.times.with_index can be used as a function object
  51         auto z = hana::int_c<5>.times.with_index;
  52         (void)z;
  53
  54         // make sure we're calling the function in the right order
  55         int current = 0;
  56         hana::int_c<5>.times.with_index([&](auto i) {
  57             BOOST_HANA_RUNTIME_CHECK(hana::value(i) == current);
  58             ++current;
  59         });
  60     }
  61 }