libstdc++-v3/testsuite/experimental/functional/not_fn.cc

   1 // Copyright (C) 2014-2016 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-std=gnu++14" }
  19
  20 #include <experimental/functional>
  21 #include <testsuite_hooks.h>
  22
  23 using std::experimental::not_fn;
  24
  25 int func(int, char) { return 0; }
  26
  27 struct F
  28 {
  29   bool operator()() { return false; }
  30   bool operator()() const { return true; }
  31   bool operator()(int) { return false; }
  32   bool operator()(int) volatile { return true; }
  33 };
  34
  35 void
  36 test01()
  37 {
  38   auto f1 = not_fn(func);
  39   VERIFY( f1(1, '2') == true );
  40
  41   auto f2 = not_fn( [] { return true; } );
  42   VERIFY( f2() == false );
  43
  44   auto f3 = not_fn( F{} );
  45   VERIFY( f3() == true );
  46   VERIFY( f3(1) == true );
  47   const auto f4 = f3;
  48   VERIFY( f4() == false );
  49   volatile auto f5 = f3;
  50   VERIFY( f5(1) == false );
  51 }
  52
  53 template<typename F, typename Arg>
  54 auto foo(F f, Arg arg) -> decltype(not_fn(f)(arg)) { return not_fn(f)(arg); }
  55
  56 template<typename F, typename Arg>
  57 auto foo(F f, Arg arg) -> decltype(not_fn(f)()) { return not_fn(f)(); }
  58
  59 struct negator
  60 {
  61     bool operator()(int) const { return false; }
  62     void operator()() const {}
  63 };
  64
  65 void
  66 test02()
  67 {
  68   foo(negator{}, 1); // PR libstdc++/66998
  69 }
  70
  71 void
  72 test03()
  73 {
  74   struct X { bool b; };
  75   X x{ false };
  76   VERIFY( not_fn(&X::b)(x) );
  77 }
  78
  79 int
  80 main()
  81 {
  82   test01();
  83   test02();
  84   test03();
  85 }