libstdc++-v3/testsuite/20_util/tuple/tuple_element.cc

   1 // { dg-do compile { target c++11 } }
   2
   3 // Copyright (C) 2007-2022 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 // Tuple
  21
  22 #include <tuple>
  23
  24 using namespace std;
  25
  26 struct foo
  27 { };
  28
  29 int
  30 main()
  31 {
  32   // As foo isn't constructible from anything else, this
  33   // lets us check if type is returning foo when it should
  34   foo q1;
  35   tuple_element<0,tuple<foo,void,int> >::type q2(q1);
  36   tuple_element<2,tuple<void,int,foo> >::type q3(q1);
  37   tuple_element<0,const tuple<foo,void,int> >::type q4(q1);
  38   tuple_element<2,const tuple<void,int,foo> >::type q5(q1);
  39   tuple_element<0,volatile tuple<foo,void,int> >::type q6(q1);
  40   tuple_element<2,volatile tuple<void,int,foo> >::type q7(q1);
  41   tuple_element<0,const volatile tuple<foo,void,int> >::type q8(q1);
  42   tuple_element<2,const volatile tuple<void,int,foo> >::type q9(q1);
  43 }