libstdc++-v3/testsuite/20_util/tuple/creation_functions/forward_as_tuple.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // 2010-04-30  Paolo Carlini  <paolo.carlini@oracle.com>
   4 //
   5 // Copyright (C) 2010-2024 Free Software Foundation, Inc.
   6 //
   7 // This file is part of the GNU ISO C++ Library.  This library is free
   8 // software; you can redistribute it and/or modify it under the
   9 // terms of the GNU General Public License as published by the
  10 // Free Software Foundation; either version 3, or (at your option)
  11 // any later version.
  12
  13 // This library is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License along
  19 // with this library; see the file COPYING3.  If not see
  20 // <http://www.gnu.org/licenses/>.
  21
  22 // Tuple
  23
  24 #include <tuple>
  25 #include <type_traits>
  26 #include <testsuite_hooks.h>
  27
  28 void
  29 test01()
  30 {
  31   std::forward_as_tuple();
  32
  33   VERIFY( std::get<0>(std::forward_as_tuple(-1)) == -1 );
  34   VERIFY( (std::is_same<decltype(std::forward_as_tuple(-1)),
  35            std::tuple<int&&>>::value) );
  36
  37   const int i1 = 1;
  38   const int i2 = 2;
  39   const double d1 = 4.0;
  40   auto t1 = std::forward_as_tuple(i1, i2, d1);
  41   VERIFY( (std::is_same<decltype(t1), std::tuple<const int&,
  42            const int&, const double&>>::value) );
  43   VERIFY( std::get<0>(t1) == i1 );
  44   VERIFY( std::get<1>(t1) == i2 );
  45   VERIFY( std::get<2>(t1) == d1 );
  46
  47   typedef const int a_type1[3];
  48   a_type1 a1 = { -1, 1, 2 };
  49   auto t2 = std::forward_as_tuple(a1);
  50   VERIFY( (std::is_same<decltype(t2), std::tuple<a_type1&>>::value) );
  51   VERIFY( std::get<0>(t2)[0] == a1[0] );
  52   VERIFY( std::get<0>(t2)[1] == a1[1] );
  53   VERIFY( std::get<0>(t2)[2] == a1[2] );
  54
  55   typedef int a_type2[2];
  56   a_type2 a2 = { 2, -2 };
  57   volatile int i4 = 1;
  58   auto t3 = std::forward_as_tuple(a2, i4);
  59   VERIFY( (std::is_same<decltype(t3), std::tuple<a_type2&,
  60            volatile int&>>::value) );
  61   VERIFY( std::get<0>(t3)[0] == a2[0] );
  62   VERIFY( std::get<0>(t3)[1] == a2[1] );
  63   VERIFY( std::get<1>(t3) == i4 );
  64 }
  65
  66 int main()
  67 {
  68   test01();
  69   return 0;
  70 }