libstdc++-v3/testsuite/20_util/pair/astuple/astuple.cc

   1 // { dg-do compile { target c++11 } }
   2
   3 // Copyright (C) 2013-2019 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10 //
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15 //
  16 // You should have received a copy of the GNU General Public License along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 // NB: Don't include any other headers in this file.
  21 // LWG 2212 requires <utility> to define tuple_size<cv T> and
  22 // tuple_element<cv T> specializations.
  23 #include <utility>
  24
  25 typedef std::pair<int, long> test_type;
  26
  27 static_assert( std::tuple_size<test_type>::value == 2, "size is 2" );
  28 static_assert( std::tuple_size<const test_type>::value == 2, "size is 2" );
  29 static_assert( std::tuple_size<volatile test_type>::value == 2, "size is 2" );
  30 static_assert( std::tuple_size<const volatile test_type>::value == 2,
  31                "size is 2" );
  32
  33 template<std::size_t N, typename T>
  34   using Tuple_elt = typename std::tuple_element<N, T>::type;
  35
  36 // This relies on the fact that <utility> includes <type_traits>:
  37 using std::is_same;
  38
  39 static_assert( is_same<Tuple_elt<0, test_type>, test_type::first_type>::value,
  40                "first type is int" );
  41
  42 static_assert( is_same<Tuple_elt<1, test_type>, test_type::second_type>::value,
  43                "second type is long" );
  44
  45 static_assert( is_same<Tuple_elt<0, const test_type>,
  46                const test_type::first_type>::value,
  47                "first type is const int" );
  48
  49 static_assert( is_same<Tuple_elt<1, const test_type>,
  50                const test_type::second_type>::value,
  51                "second type is const long" );
  52
  53 static_assert( is_same<Tuple_elt<0, volatile test_type>,
  54                volatile test_type::first_type>::value,
  55                "first type is volatile int" );
  56
  57 static_assert( is_same<Tuple_elt<1, volatile test_type>,
  58                volatile test_type::second_type>::value,
  59                "second type is volatile long" );
  60
  61 static_assert( is_same<Tuple_elt<0, const volatile test_type>,
  62                const volatile test_type::first_type>::value,
  63                "first type is const volatile int" );
  64
  65 static_assert( is_same<Tuple_elt<1, const volatile test_type>,
  66                const volatile test_type::second_type>::value,
  67                "second type is const volatile long" );