6.cc

linux下编程用 编译软件

// 2005-01-15 Douglas Gregor <[e-mail]>
//
// Copyright (C) 2005 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.

// 3.7.2 polymorphic function object wrapper
#include <tr1/functional>
#include <testsuite_hooks.h>
#include <testsuite_tr1.h>

using namespace __gnu_test;

bool test __attribute__((unused)) = true;

struct secret {};

struct noncopyable_function_object_type
{
  noncopyable_function_object_type(secret) {}

  int operator()() const { return 42; }
  int operator()()       { return 17; }

 private:
  noncopyable_function_object_type();
  noncopyable_function_object_type(const noncopyable_function_object_type&);
  void operator=(const noncopyable_function_object_type&);
};

// Put reference_wrappers into function<> wrappers
void test06()
{
  using std::tr1::function;
  using std::tr1::ref;
  using std::tr1::cref;

  secret password;
  noncopyable_function_object_type x(password);

  function<int()> f(ref(x));
  VERIFY( f );
  VERIFY( f() == 17 );
  VERIFY( f.target_type() == typeid(noncopyable_function_object_type) );
  VERIFY( f.target<noncopyable_function_object_type>() == &x );

  function<int()> g = f;
  VERIFY( g );
  VERIFY( g() == 17 );
  VERIFY( g.target_type() == typeid(noncopyable_function_object_type) );
  VERIFY( g.target<noncopyable_function_object_type>() == &x );

  function<int()> h = cref(x);
  VERIFY( h );
  VERIFY( h() == 42 );
  VERIFY( h.target_type() == typeid(noncopyable_function_object_type) );
  VERIFY( h.target<const noncopyable_function_object_type>() == &x );
  VERIFY( h.target<const noncopyable_function_object_type>() == &x );

  const function<int()>& hc = h;
  VERIFY( h.target<noncopyable_function_object_type>() == 0 );
  VERIFY( hc.target<noncopyable_function_object_type>() == &x );
}

int main()
{
  test06();
  return 0;
}