libstdc++-v3/testsuite/tr1/3_function_objects/function/7.cc

   1 // 2005-01-15 Douglas Gregor <dgregor@cs.indiana.edu>
   2 //
   3 // Copyright (C) 2005-2019 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 // 3.7.2 polymorphic function object wrapper
  21 #include <tr1/functional>
  22 #include <testsuite_hooks.h>
  23 #include <testsuite_tr1.h>
  24
  25 using namespace __gnu_test;
  26
  27 // Put reference_wrappers to function pointers into function<> wrappers
  28 void test07()
  29 {
  30   using std::tr1::function;
  31   using std::tr1::ref;
  32   using std::tr1::cref;
  33
  34   int (*fptr)(float) = truncate_float;
  35
  36   function<int(float)> f1(ref(fptr));
  37   VERIFY( f1 );
  38   VERIFY( !!f1 );
  39   VERIFY( !(f1 == 0) );
  40   VERIFY( !(0 == f1) );
  41   VERIFY( f1 != 0 );
  42   VERIFY( 0 != f1 );
  43
  44   // Invocation
  45   VERIFY( f1(3.1f) == 3 );
  46
  47   // target_type and target() functions
  48   const function<int(float)>& f1c = f1;
  49   VERIFY( typeid(int(*)(float)) == f1.target_type() );
  50   VERIFY( f1.target<int(*)(float)>() != 0 );
  51   VERIFY( f1.target<int(*)(float)>() == &fptr );
  52   VERIFY( f1c.target<int(*)(float)>() != 0 );
  53   VERIFY( f1c.target<int(*)(float)>() == &fptr );
  54
  55   function<int(float)> f2(cref(fptr));
  56   VERIFY( f2 );
  57   VERIFY( !!f2 );
  58   VERIFY( !(f2 == 0) );
  59   VERIFY( !(0 == f2) );
  60   VERIFY( f2 != 0 );
  61   VERIFY( 0 != f2 );
  62
  63   // Invocation
  64   VERIFY( f2(3.1f) == 3 );
  65
  66   // target_type and target() functions
  67   const function<int(float)>& f2c = f2;
  68   VERIFY( typeid(int(*)(float)) == f2.target_type() );
  69   VERIFY( f2.target<int(*)(float)>() == 0 );
  70   VERIFY( f2.target<int(* const)(float)>() == &fptr );
  71   VERIFY( f2c.target<int(*)(float)>() != 0 );
  72   VERIFY( f2c.target<int(*)(float)>() == &fptr );
  73 }
  74
  75 int main()
  76 {
  77   test07();
  78   return 0;
  79 }