ceph/src/boost/libs/hof/test/mutable.cpp

   1 /*=============================================================================
   2     Copyright (c) 2017 Paul Fultz II
   3     mutable.cpp
   4     Distributed under the Boost Software License, Version 1.0. (See accompanying
   5     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   6 ==============================================================================*/
   7 #include <boost/hof/mutable.hpp>
   8 #include <boost/hof/lazy.hpp>
   9 #include <boost/hof/detail/move.hpp>
  10 #include <memory>
  11 #include "test.hpp"
  12
  13 struct mutable_fun
  14 {
  15     int x;
  16     mutable_fun() noexcept
  17     : x(1)
  18     {}
  19
  20     int operator()(int i) noexcept
  21     {
  22         x+=i;
  23         return x;
  24     }
  25 };
  26
  27 #if BOOST_HOF_HAS_NOEXCEPT_DEDUCTION
  28 BOOST_HOF_TEST_CASE()
  29 {
  30     static_assert(noexcept(boost::hof::mutable_(mutable_fun())(3)), "noexcept mutable_");
  31 }
  32 #endif
  33
  34 BOOST_HOF_TEST_CASE()
  35 {
  36     BOOST_HOF_TEST_CHECK(boost::hof::mutable_(mutable_fun())(3) == 4);
  37 }
  38
  39 BOOST_HOF_TEST_CASE()
  40 {
  41     auto mut_fun = mutable_fun();
  42     auto by_5 = boost::hof::lazy(boost::hof::mutable_(std::ref(mut_fun)))(5);
  43     BOOST_HOF_TEST_CHECK(by_5() == 6);
  44     BOOST_HOF_TEST_CHECK(by_5() == 11);
  45 }
  46
  47 struct mutable_move_fun
  48 {
  49     std::unique_ptr<int> x;
  50     mutable_move_fun() : x(new int(1))
  51     {}
  52
  53     int operator()(int i)
  54     {
  55         *x+=i;
  56         return *x;
  57     }
  58 };
  59
  60 BOOST_HOF_TEST_CASE()
  61 {
  62     BOOST_HOF_TEST_CHECK(boost::hof::mutable_(mutable_move_fun())(3) == 4);
  63 }
  64
  65 BOOST_HOF_TEST_CASE()
  66 {
  67     auto mut_fun = mutable_move_fun();
  68     auto by_5 = boost::hof::lazy(boost::hof::mutable_(boost::hof::move(mut_fun)))(5);
  69     BOOST_HOF_TEST_CHECK(by_5() == 6);
  70     BOOST_HOF_TEST_CHECK(by_5() == 11);
  71 }
  72