libstdc++-v3/testsuite/20_util/function/3.cc

   1 // { dg-do run { target c++11 } }
   2 // { dg-require-effective-target hosted }
   3
   4 // 2005-01-15 Douglas Gregor <dgregor@cs.indiana.edu>
   5 //
   6 // Copyright (C) 2005-2024 Free Software Foundation, Inc.
   7 //
   8 // This file is part of the GNU ISO C++ Library.  This library is free
   9 // software; you can redistribute it and/or modify it under the
  10 // terms of the GNU General Public License as published by the
  11 // Free Software Foundation; either version 3, or (at your option)
  12 // any later version.
  13 //
  14 // This library is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18 //
  19 // You should have received a copy of the GNU General Public License along
  20 // with this library; see the file COPYING3.  If not see
  21 // <http://www.gnu.org/licenses/>.
  22
  23 // 20.7.15 polymorphic function object wrapper
  24 #include <functional>
  25 #include <testsuite_hooks.h>
  26 #include <testsuite_tr1.h>
  27
  28 using namespace __gnu_test;
  29
  30 // Put nearly-matching function pointers into function<> wrappers
  31 void test03()
  32 {
  33   using std::function;
  34
  35   function<int(float)> f1(truncate_double);
  36   VERIFY( f1 );
  37   VERIFY( !!f1 );
  38   VERIFY( !(f1 == 0) );
  39   VERIFY( !(0 == f1) );
  40   VERIFY( f1 != 0 );
  41   VERIFY( 0 != f1 );
  42
  43   // Copy-construction
  44   function<int(float)> f2(f1);
  45   VERIFY( f2 );
  46
  47   // Invocation
  48   VERIFY( f1(3.1f) == 3 );
  49   VERIFY( f2(3.1f) == 3 );
  50
  51   // Assignment to zero
  52   f1 = 0;
  53   VERIFY( !f1 );
  54
  55   // Swap
  56   f1.swap(f2);
  57   VERIFY( f1 );
  58   VERIFY( !f2 );
  59   VERIFY( f1(3.1f) == 3 );
  60
  61   // Assignment from a function pointer
  62   f2 = truncate_double;
  63   VERIFY( f2(3.1f) == 3 );
  64
  65   // target_type and target() functions
  66   const function<int(float)>& f1c = f1;
  67 #if __cpp_rtti
  68   VERIFY( typeid(long(*)(double)) == f1.target_type() );
  69 #endif
  70   VERIFY( f2.target<long(*)(double)>() != 0 );
  71   VERIFY( *f2.target<long(*)(double)>() == &truncate_double );
  72   VERIFY( f1c.target<long(*)(double)>() != 0 );
  73   VERIFY( *f1c.target<long(*)(double)>() == &truncate_double );
  74 }
  75
  76 int main()
  77 {
  78   test03();
  79   return 0;
  80 }