libstdc++-v3/testsuite/26_numerics/transform_reduce/constexpr.cc

   1 // Copyright (C) 2020-2022 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-std=gnu++2a" }
  19 // { dg-do compile { target c++2a } }
  20
  21 #include <functional>
  22 #include <numeric>
  23
  24 constexpr bool
  25 test01()
  26 {
  27   int x[5] = {1,2,3,4,5};
  28   int y[5] = {2,4,6,8,10};
  29   auto ret = std::transform_reduce(x, x+5, y, 0);
  30   return ret == 110;
  31 }
  32
  33 static_assert(test01());
  34
  35 constexpr bool
  36 test02()
  37 {
  38   int x[5] = {1,2,3,4,5};
  39   int y[5] = {2,4,6,8,10};
  40   auto ret = std::transform_reduce(x, x+5, y, 1,
  41                                    std::multiplies{}, std::plus{});
  42   return ret == 3*6*9*12*15;
  43 }
  44
  45 static_assert(test02());
  46
  47 constexpr bool
  48 test03()
  49 {
  50   int x[5] = {1,2,3,4,5};
  51   auto ret = std::transform_reduce(x, x+5, 0, std::plus{}, std::negate{});
  52   return ret == -15;
  53 }
  54
  55 static_assert(test03());