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// -*- C++ -*-
#ifndef WIBBLE_EMPTY_H
#define WIBBLE_EMPTY_H
/*
* Degenerated container to hold a single value
*
* Copyright (C) 2006 Enrico Zini <enrico@debian.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <cstddef>
#include <bits/stl_iterator_base_types.h>
namespace wibble {
template<typename T>
class Empty
{
public:
typedef T value_type;
class const_iterator : public std::iterator<std::forward_iterator_tag, const T, void, const T*, const T&>
{
public:
const T& operator*() const { return *(T*)0; }
const T* operator->() const { return 0; }
const_iterator& operator++() { return *this; }
bool operator==(const const_iterator&) const { return true; }
bool operator!=(const const_iterator&) const { return false; }
};
class iterator : public std::iterator<std::forward_iterator_tag, T, void, T*, T&>
{
public:
T& operator*() const { return *(T*)0; }
T* operator->() const { return 0; }
iterator& operator++() { return *this; }
bool operator==(const iterator&) const { return true; }
bool operator!=(const iterator&) const { return false; }
};
bool empty() const { return true; }
size_t size() const { return 0; }
iterator begin() { return iterator(); }
iterator end() { return iterator(); }
const_iterator begin() const { return const_iterator(); }
const_iterator end() const { return const_iterator(); }
};
}
// vim:set ts=4 sw=4:
#endif
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