libstdc++-v3/testsuite/20_util/function_objects/mem_fn/forward.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // Copyright (C) 2012-2023 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 along
  17 // with this library; see the file COPYING3.  If not see
  18 // <http://www.gnu.org/licenses/>.
  19
  20 #include <functional>
  21 #include <testsuite_hooks.h>
  22
  23 struct Counter
  24 {
  25   Counter() = default;
  26   Counter(const Counter&) { ++count; }
  27
  28   static int count;
  29 };
  30
  31 int Counter::count = 0;
  32
  33 struct X
  34 {
  35   int func(Counter, int i) { return i; }
  36   char func_c(Counter, char c) const { return c; }
  37   short func_v(Counter, short s) volatile { return s; }
  38   double func_cv(Counter, double d) const volatile { return d; }
  39 };
  40
  41 void test01()
  42 {
  43   Counter c;
  44   X x;
  45
  46   std::mem_fn( &X::func )( x, c, 0 );
  47   VERIFY( Counter::count == 1 );
  48
  49   std::mem_fn( &X::func_c )( x, c, 0 );
  50   VERIFY( Counter::count == 2 );
  51
  52   std::mem_fn( &X::func_v )( x, c, 0 );
  53   VERIFY( Counter::count == 3 );
  54
  55   std::mem_fn( &X::func_cv )( x, c, 0 );
  56   VERIFY( Counter::count == 4 );
  57 }
  58
  59 int main()
  60 {
  61   test01();
  62 }