libstdc++-v3/testsuite/experimental/any/misc/any_cast.cc

   1 // { dg-do run { target c++14 } }
   2
   3 // Copyright (C) 2014-2019 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 <experimental/any>
  21 #include <string>
  22 #include <cstring>
  23 #include <testsuite_hooks.h>
  24
  25 using std::experimental::any;
  26 using std::experimental::any_cast;
  27
  28 void test01()
  29 {
  30   using std::string;
  31   using std::strcmp;
  32
  33   // taken from example in N3804 proposal
  34
  35   any x(5);                                   // x holds int
  36   VERIFY(any_cast<int>(x) == 5);              // cast to value
  37   any_cast<int&>(x) = 10;                     // cast to reference
  38   VERIFY(any_cast<int>(x) == 10);
  39
  40   x = "Meow";                                 // x holds const char*
  41   VERIFY(strcmp(any_cast<const char*>(x), "Meow") == 0);
  42   any_cast<const char*&>(x) = "Harry";
  43   VERIFY(strcmp(any_cast<const char*>(x), "Harry") == 0);
  44
  45   x = string("Meow");                         // x holds string
  46   string s, s2("Jane");
  47   s = move(any_cast<string&>(x));             // move from any
  48   VERIFY(s == "Meow");
  49   any_cast<string&>(x) = move(s2);            // move to any
  50   VERIFY(any_cast<const string&>(x) == "Jane");
  51
  52   string cat("Meow");
  53   const any y(cat);                           // const y holds string
  54   VERIFY(any_cast<const string&>(y) == cat);
  55 }
  56
  57 void test02()
  58 {
  59   using std::experimental::bad_any_cast;
  60   any x(1);
  61   auto p = any_cast<double>(&x);
  62   VERIFY(p == nullptr);
  63
  64   x = 1.0;
  65   p = any_cast<double>(&x);
  66   VERIFY(p != nullptr);
  67
  68   x = any();
  69   p = any_cast<double>(&x);
  70   VERIFY(p == nullptr);
  71
  72   try {
  73     any_cast<double>(x);
  74     VERIFY(false);
  75   } catch (const bad_any_cast&) {
  76   }
  77 }
  78
  79 static int move_count = 0;
  80
  81 void test03()
  82 {
  83   struct MoveEnabled
  84   {
  85     MoveEnabled(MoveEnabled&&)
  86     {
  87       ++move_count;
  88     }
  89     MoveEnabled() = default;
  90     MoveEnabled(const MoveEnabled&) = default;
  91   };
  92   MoveEnabled m;
  93   MoveEnabled m2 = any_cast<MoveEnabled>(any(m));
  94   VERIFY(move_count == 1);
  95   MoveEnabled&& m3 = any_cast<MoveEnabled&&>(any(m));
  96   VERIFY(move_count == 1);
  97   struct MoveDeleted
  98   {
  99     MoveDeleted(MoveDeleted&&) = delete;
 100     MoveDeleted() = default;
 101     MoveDeleted(const MoveDeleted&) = default;
 102   };
 103   MoveDeleted md;
 104   MoveDeleted&& md2 = any_cast<MoveDeleted>(any(std::move(md)));
 105   MoveDeleted&& md3 = any_cast<MoveDeleted&&>(any(std::move(md)));
 106 }
 107
 108 void test04()
 109 {
 110   // PR libstdc++/69321
 111   struct noncopyable {
 112     noncopyable(noncopyable const&) = delete;
 113   };
 114
 115   any a;
 116   auto p = any_cast<noncopyable>(&a);
 117   VERIFY( p == nullptr );
 118 }
 119
 120 int main()
 121 {
 122   test01();
 123   test02();
 124   test03();
 125   test04();
 126 }