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

   1 // Copyright (C) 2014-2023 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-do run { target c++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 };
  33
  34 void
  35 test01()
  36 {
  37   auto f1 = not_fn(func);
  38   VERIFY( f1(1, '2') == true );
  39
  40   auto f2 = not_fn( [] { return true; } );
  41   VERIFY( f2() == false );
  42
  43   auto f3 = not_fn( F{} );
  44   VERIFY( f3() == true );
  45   VERIFY( f3(1) == true );
  46   const auto f4 = f3;
  47   VERIFY( f4() == false );
  48 }
  49
  50 template<typename F, typename Arg>
  51 auto foo(F f, Arg arg) -> decltype(not_fn(f)(arg)) { return not_fn(f)(arg); }
  52
  53 template<typename F, typename Arg>
  54 auto foo(F f, Arg arg) -> decltype(not_fn(f)()) { return not_fn(f)(); }
  55
  56 struct negator
  57 {
  58     bool operator()(int) const { return false; }
  59     void operator()() const {}
  60 };
  61
  62 void
  63 test02()
  64 {
  65   foo(negator{}, 1); // PR libstdc++/66998
  66 }
  67
  68 void
  69 test03()
  70 {
  71   struct X { bool b; };
  72   X x{ false };
  73   VERIFY( not_fn(&X::b)(x) );
  74 }
  75
  76 void
  77 test04()
  78 {
  79   struct abstract { virtual void f() = 0; };
  80   struct derived : abstract { void f() { } };
  81   struct F { bool operator()(abstract&) { return false; } };
  82   F f;
  83   derived d;
  84   VERIFY( not_fn(f)(d) );
  85 }
  86
  87 void
  88 test05()
  89 {
  90   auto nf = std::experimental::not_fn([] { return false; });
  91   auto copy(nf); // PR libstdc++/70564
  92 }
  93
  94 int
  95 main()
  96 {
  97   test01();
  98   test02();
  99   test03();
 100   test04();
 101   test05();
 102 }