libstdc++-v3/testsuite/experimental/optional/constexpr/observers/5.cc

   1 // { dg-options "-std=gnu++14" }
   2 // { dg-do compile }
   3
   4 // Copyright (C) 2013-2016 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a moved_to of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <experimental/optional>
  22
  23 struct value_type
  24 {
  25   int i;
  26 };
  27
  28 int main()
  29 {
  30   {
  31     constexpr std::experimental::optional<value_type> o = std::experimental::nullopt;
  32     static_assert( !o, "" );
  33   }
  34
  35   {
  36     constexpr std::experimental::optional<value_type> o { value_type { 51 } };
  37     static_assert( o, "" );
  38   }
  39 }