// Stream iterators
	
	// Copyright (C) 2001-2013 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 3, 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.
	
	// Under Section 7 of GPL version 3, you are granted additional
	// permissions described in the GCC Runtime Library Exception, version
	// 3.1, as published by the Free Software Foundation.
	
	// You should have received a copy of the GNU General Public License and
	// a copy of the GCC Runtime Library Exception along with this program;
	// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
	// <http://www.gnu.org/licenses/>.
	
	/** @file bits/stream_iterator.h
	 *  This is an internal header file, included by other library headers.
	 *  Do not attempt to use it directly. @headername{iterator}
	 */
	
	#ifndef _STREAM_ITERATOR_H
	#define _STREAM_ITERATOR_H 1
	
	#pragma GCC system_header
	
	#include <debug/debug.h>
	
	namespace std _GLIBCXX_VISIBILITY(default)
	{
	_GLIBCXX_BEGIN_NAMESPACE_VERSION
	
	  /**
	   * @addtogroup iterators
	   * @{
	   */
	
	  /// Provides input iterator semantics for streams.
	  template<typename _Tp, typename _CharT = char,
	           typename _Traits = char_traits<_CharT>, typename _Dist = ptrdiff_t>
	    class istream_iterator
	    : public iterator<input_iterator_tag, _Tp, _Dist, const _Tp*, const _Tp&>
	    {
	    public:
	      typedef _CharT                         char_type;
	      typedef _Traits                        traits_type;
	      typedef basic_istream<_CharT, _Traits> istream_type;
	
	    private:
	      istream_type*	_M_stream;
	      _Tp		_M_value;
	      bool		_M_ok;
	
	    public:
	      ///  Construct end of input stream iterator.
	      _GLIBCXX_CONSTEXPR istream_iterator()
	      : _M_stream(0), _M_value(), _M_ok(false) {}
	
	      ///  Construct start of input stream iterator.
	      istream_iterator(istream_type& __s)
	      : _M_stream(&__s)
	      { _M_read(); }
	
	      istream_iterator(const istream_iterator& __obj)
	      : _M_stream(__obj._M_stream), _M_value(__obj._M_value),
	        _M_ok(__obj._M_ok)
	      { }
	
	      const _Tp&
	      operator*() const
	      {
		__glibcxx_requires_cond(_M_ok,
					_M_message(__gnu_debug::__msg_deref_istream)
					._M_iterator(*this));
		return _M_value;
	      }
	
	      const _Tp*
	      operator->() const { return &(operator*()); }
	
	      istream_iterator&
	      operator++()
	      {
		__glibcxx_requires_cond(_M_ok,
					_M_message(__gnu_debug::__msg_inc_istream)
					._M_iterator(*this));
		_M_read();
		return *this;
	      }
	
	      istream_iterator
	      operator++(int)
	      {
		__glibcxx_requires_cond(_M_ok,
					_M_message(__gnu_debug::__msg_inc_istream)
					._M_iterator(*this));
		istream_iterator __tmp = *this;
		_M_read();
		return __tmp;
	      }
	
	      bool
	      _M_equal(const istream_iterator& __x) const
	      { return (_M_ok == __x._M_ok) && (!_M_ok || _M_stream == __x._M_stream); }
	
	    private:
	      void
	      _M_read()
	      {
		_M_ok = (_M_stream && *_M_stream) ? true : false;
		if (_M_ok)
		  {
		    *_M_stream >> _M_value;
		    _M_ok = *_M_stream ? true : false;
		  }
	      }
	    };
	
	  ///  Return true if x and y are both end or not end, or x and y are the same.
	  template<typename _Tp, typename _CharT, typename _Traits, typename _Dist>
	    inline bool
	    operator==(const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __x,
		       const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __y)
	    { return __x._M_equal(__y); }
	
	  ///  Return false if x and y are both end or not end, or x and y are the same.
	  template <class _Tp, class _CharT, class _Traits, class _Dist>
	    inline bool
	    operator!=(const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __x,
		       const istream_iterator<_Tp, _CharT, _Traits, _Dist>& __y)
	    { return !__x._M_equal(__y); }
	
	  /**
	   *  @brief  Provides output iterator semantics for streams.
	   *
	   *  This class provides an iterator to write to an ostream.  The type Tp is
	   *  the only type written by this iterator and there must be an
	   *  operator<<(Tp) defined.
	   *
	   *  @tparam  _Tp  The type to write to the ostream.
	   *  @tparam  _CharT  The ostream char_type.
	   *  @tparam  _Traits  The ostream char_traits.
	  */
	  template<typename _Tp, typename _CharT = char,
	           typename _Traits = char_traits<_CharT> >
	    class ostream_iterator
	    : public iterator<output_iterator_tag, void, void, void, void>
	    {
	    public:
	      //@{
	      /// Public typedef
	      typedef _CharT                         char_type;
	      typedef _Traits                        traits_type;
	      typedef basic_ostream<_CharT, _Traits> ostream_type;
	      //@}
	
	    private:
	      ostream_type*	_M_stream;
	      const _CharT*	_M_string;
	
	    public:
	      /// Construct from an ostream.
	      ostream_iterator(ostream_type& __s) : _M_stream(&__s), _M_string(0) {}
	
	      /**
	       *  Construct from an ostream.
	       *
	       *  The delimiter string @a c is written to the stream after every Tp
	       *  written to the stream.  The delimiter is not copied, and thus must
	       *  not be destroyed while this iterator is in use.
	       *
	       *  @param  __s  Underlying ostream to write to.
	       *  @param  __c  CharT delimiter string to insert.
	      */
	      ostream_iterator(ostream_type& __s, const _CharT* __c)
	      : _M_stream(&__s), _M_string(__c)  { }
	
	      /// Copy constructor.
	      ostream_iterator(const ostream_iterator& __obj)
	      : _M_stream(__obj._M_stream), _M_string(__obj._M_string)  { }
	
	      /// Writes @a value to underlying ostream using operator<<.  If
	      /// constructed with delimiter string, writes delimiter to ostream.
	      ostream_iterator&
	      operator=(const _Tp& __value)
	      {
		__glibcxx_requires_cond(_M_stream != 0,
					_M_message(__gnu_debug::__msg_output_ostream)
					._M_iterator(*this));
		*_M_stream << __value;
		if (_M_string) *_M_stream << _M_string;
		return *this;
	      }
	
	      ostream_iterator&
	      operator*()
	      { return *this; }
	
	      ostream_iterator&
	      operator++()
	      { return *this; }
	
	      ostream_iterator&
	      operator++(int)
	      { return *this; }
	    };
	
	  // @} group iterators
	
	_GLIBCXX_END_NAMESPACE_VERSION
	} // namespace
	
	#endif