libstdc++-v3/testsuite/23_containers/queue/requirements/constructible.cc

   1 // { dg-do compile { target c++11 } }
   2
   3 // Copyright (C) 2017-2023 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
  17 // along with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20
  21 // This file tests explicit instantiation of library containers.
  22
  23 #include <queue>
  24
  25 using std::queue;
  26
  27 template<typename A>
  28 constexpr bool default_constructible()
  29 { return std::is_default_constructible<A>::value; }
  30
  31 static_assert(default_constructible<queue<int>>(), "queue<int>");
  32
  33 struct NonDefaultConstructible : std::deque<int> {
  34   NonDefaultConstructible(int) { }
  35 };
  36 static_assert(!default_constructible<queue<int, NonDefaultConstructible>>(),
  37               "queue<int, NonDefaultConstructible>");