the output range may overlap [first,last).
  */
  template<typename _BI1, typename _BI2>
    inline _BI2
    move_backward(_BI1 __first, _BI1 __last, _BI2 __result)
    {
      // concept requirements
      __glibcxx_function_requires(_BidirectionalIteratorConcept<_BI1>)
      __glibcxx_function_requires(_Mutable_BidirectionalIteratorConcept<_BI2>)
      __glibcxx_function_requires(_ConvertibleConcept<
	    typename iterator_traits<_BI1>::value_type,
	    typename iterator_traits<_BI2>::value_type>)
      __glibcxx_requires_valid_range(__first, __last);

      return (std::__copy_move_backward_a2<true>
	      (std::__miter_base<_BI1>::__b(__first),
	       std::__miter_base<_BI1>::__b(__last), __result));
    }

#define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::move_backward(_Tp, _Up, _Vp)
#else
#define _GLIBCXX_MOVE_BACKWARD3(_Tp, _Up, _Vp) std::copy_backward(_Tp, _Up, _Vp)
#endif

  template<typename _ForwardIterator, typename _Tp>
    inline typename
    __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, void>::__type
    __fill_a(_ForwardIterator __first, _ForwardIterator __last,
 	     const _Tp& __value)
    {
      for (; __first != __last; ++__first)
	*__first = __value;
    }
    
  template<typename _ForwardIterator, typename _Tp>
    inline typename
    __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, void>::__type
    __fill_a(_ForwardIterator __first, _ForwardIterator __last,
	     const _Tp& __value)
    {
      const _Tp __tmp = __value;
      for (; __first != __last; ++__first)
	*__first = __tmp;
    }

  // Specialization: for char types we can use memset.
  template<typename _Tp>
    inline typename
    __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, void>::__type
    __fill_a(_Tp* __first, _Tp* __last, const _Tp& __c)
    {
      const _Tp __tmp = __c;
      __builtin_memset(__first, static_cast<unsigned char>(__tmp),
		       __last - __first);
    }

  /**
   *  @brief Fills the range [first,last) with copies of value.
   *  @param  first  A forward iterator.
   *  @param  last   A forward iterator.
   *  @param  value  A reference-to-const of arbitrary type.
   *  @return   Nothing.
   *
   *  This function fills a range with copies of the same value.  For char
   *  types filling contiguous areas of memory, this becomes an inline call
   *  to @c memset or @c wmemset.
  */
  template<typename _ForwardIterator, typename _Tp>
    inline void
    fill(_ForwardIterator __first, _ForwardIterator __last, const _Tp& __value)
    {
      // concept requirements
      __glibcxx_function_requires(_Mutable_ForwardIteratorConcept<
				  _ForwardIterator>)
      __glibcxx_requires_valid_range(__first, __last);

      std::__fill_a(std::__niter_base<_ForwardIterator>::__b(__first),
		    std::__niter_base<_ForwardIterator>::__b(__last), __value);
    }

  template<typename _OutputIterator, typename _Size, typename _Tp>
    inline typename
    __gnu_cxx::__enable_if<!__is_scalar<_Tp>::__value, _OutputIterator>::__type
    __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value)
    {
      for (; __n > 0; --__n, ++__first)
	*__first = __value;
      return __first;
    }

  template<typename _OutputIterator, typename _Size, typename _Tp>
    inline typename
    __gnu_cxx::__enable_if<__is_scalar<_Tp>::__value, _OutputIterator>::__type
    __fill_n_a(_OutputIterator __first, _Size __n, const _Tp& __value)
    {
      const _Tp __tmp = __value;
      for (; __n > 0; --__n, ++__first)
	*__first = __tmp;
      return __first;
    }

  template<typename _Size, typename _Tp>
    inline typename
    __gnu_cxx::__enable_if<__is_byte<_Tp>::__value, _Tp*>::__type
    __fill_n_a(_Tp* __first, _Size __n, const _Tp& __c)
    {
      std::__fill_a(__first, __first + __n, __c);
      return __first + __n;
    }

  /**
   *  @brief Fills the range [first,first+n) with copies of value.
   *  @param  first  An output iterator.
   *  @param  n      The count of copies to perform.
   *  @param  value  A reference-to-const of arbitrary type.
   *  @return   The iterator at first+n.
   *
   *  This function fills a range with copies of the same value.  For char
   *  types filling contiguous areas of memory, this becomes an inline call
   *  to @c memset or @ wmemset.
  */
  template<typename _OI, typename _Size, typename _Tp>
    inline _OI
    fill_n(_OI __first, _Size __n, const _Tp& __value)
    {
      // concept requirements
      __glibcxx_function_requires(_OutputIteratorConcept<_OI, _Tp>)

      return _OI(std::__fill_n_a(std::__niter_base<_OI>::__b(__first),
				 __n, __value));
    }

  template<bool _BoolType>
    struct __equal
    {
      template<typename _II1, typename _II2>
        static bool
        equal(_II1 __first1, _II1 __last1, _II2 __first2)
        {
	  for (; __first1 != __last1; ++__first1, ++__first2)
	    if (!(*__first1 == *__first2))
	      return false;
	  return true;
	}
    };

  template<>
    struct __equal<true>
    {
      template<typename _Tp>
        static bool
        equal(const _Tp* __first1, const _Tp* __last1, const _Tp* __first2)
        {
	  return !__builtin_memcmp(__first1, __first2, sizeof(_Tp)
				   * (__last1 - __first1));
	}
    };

  template<typename _II1, typename _II2>
    inline bool
    __equal_aux(_II1 __first1, _II1 __last1, _II2 __first2)
    {
      typedef typename iterator_traits<_II1>::value_type _ValueType1;
      typedef typename iterator_traits<_II2>::value_type _ValueType2;
      const bool __simple = (__is_integer<_ValueType1>::__value
	                     && __is_pointer<_II1>::__value
	                     && __is_pointer<_II2>::__value
			     && __are_same<_ValueType1, _ValueType2>::__value);

      return std::__equal<__simple>::equal(__first1, __last1, __first2);
    }


  template<typename, typename>
    struct __lc_rai
    {
      template<typename _II1, typename _II2>
        static _II1
        __newlast1(_II1, _II1 __last1, _II2, _II2)
        { return __last1; }

      template<typename _II>
        static bool
        __cnd2(_II __first, _II __last)
        { return __first != __last; }
    };

  template<>
    struct __lc_rai<random_access_iterator_tag, random_access_iterator_tag>
    {
      template<typename _RAI1, typename _RAI2>
        static _RAI1
        __newlast1(_RAI1 __first1, _RAI1 __last1,
		   _RAI2 __first2, _RAI2 __last2)
        {
	  const typename iterator_traits<_RAI1>::difference_type
	    __diff1 = __last1 - __first1;
	  const typename iterator_traits<_RAI2>::difference_type
	    __diff2 = __last2 - __first2;
	  return __diff2 < __diff1 ? __first1 + __diff2 : __last1;
	}

      template<typename _RAI>
        static bool
        __cnd2(_RAI, _RAI)
        { return true; }
    };

  template<bool _BoolType>
    struct __lexicographical_compare
    {
      template<typename _II1, typename _II2>
        static bool __lc(_II1, _II1, _II2, _II2);
    };

  template<bool _BoolType>
    template<typename _II1, typename _II2>
      bool
      __lexicographical_compare<_BoolType>::
      __lc(_II1 __first1, _II1 __last1, _II2 __first2, _II2 __last2)
      {
	typedef typename iterator_traits<_II1>::iterator_category _Category1;
	typedef typename iterator_traits<_II2>::iterator_category _Category2;
	typedef std::__lc_rai<_Category1, _Category2> 	__rai_type;
	
	__last1 = __rai_type::__newlast1(__first1, __last1,
					 __first2, __last2);
	for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2);
	     ++__first1, ++__first2)
	  {
	    if (*__first1 < *__first2)
	      return true;
	    if (*__first2 < *__first1)
	      return false;
	  }
	return __first1 == __last1 && __first2 != __last2;
      }

  template<>
    struct __lexicographical_compare<true>
    {
      template<typename _Tp, typename _Up>
        static bool
        __lc(const _Tp* __first1, const _Tp* __last1,
	     const _Up* __first2, const _Up* __last2)
	{
	  const size_t __len1 = __last1 - __first1;
	  const size_t __len2 = __last2 - __first2;
	  const int __result = __builtin_memcmp(__first1, __first2,
						std::min(__len1, __len2));
	  return __result != 0 ? __result < 0 : __len1 < __len2;
	}
    };

  template<typename _II1, typename _II2>
    inline bool
    __lexicographical_compare_aux(_II1 __first1, _II1 __last1,
				  _II2 __first2, _II2 __last2)
    {
      typedef typename iterator_traits<_II1>::value_type _ValueType1;
      typedef typename iterator_traits<_II2>::value_type _ValueType2;
      const bool __simple =
	(__is_byte<_ValueType1>::__value && __is_byte<_ValueType2>::__value
	 && !__gnu_cxx::__numeric_traits<_ValueType1>::__is_signed
	 && !__gnu_cxx::__numeric_traits<_ValueType2>::__is_signed
	 && __is_pointer<_II1>::__value
	 && __is_pointer<_II2>::__value);

      return std::__lexicographical_compare<__simple>::__lc(__first1, __last1,
							    __first2, __last2);
    }

_GLIBCXX_END_NAMESPACE

_GLIBCXX_BEGIN_NESTED_NAMESPACE(std, _GLIBCXX_STD_P)

  /**
   *  @brief Tests a range for element-wise equality.
   *  @param  first1  An input iterator.
   *  @param  last1   An input iterator.
   *  @param  first2  An input iterator.
   *  @return   A boolean true or false.
   *
   *  This compares the elements of two ranges using @c == and returns true or
   *  false depending on whether all of the corresponding elements of the
   *  ranges are equal.
  */
  template<typename _II1, typename _II2>
    inline bool
    equal(_II1 __first1, _II1 __last1, _II2 __first2)
    {
      // concept requirements
      __glibcxx_function_requires(_InputIteratorConcept<_II1>)
      __glibcxx_function_requires(_InputIteratorConcept<_II2>)
      __glibcxx_function_requires(_EqualOpConcept<
	    typename iterator_traits<_II1>::value_type,
	    typename iterator_traits<_II2>::value_type>)
      __glibcxx_requires_valid_range(__first1, __last1);

      return std::__equal_aux(std::__niter_base<_II1>::__b(__first1),
			      std::__niter_base<_II1>::__b(__last1),
			      std::__niter_base<_II2>::__b(__first2));
    }

  /**
   *  @brief Tests a range for element-wise equality.
   *  @param  first1  An input iterator.
   *  @param  last1   An input iterator.
   *  @param  first2  An input iterator.
   *  @param binary_pred A binary predicate @link s20_3_1_base
   *                  functor@endlink.
   *  @return         A boolean true or false.
   *
   *  This compares the elements of two ranges using the binary_pred
   *  parameter, and returns true or
   *  false depending on whether all of the corresponding elements of the
   *  ranges are equal.
  */
  template<typename _IIter1, typename _IIter2, typename _BinaryPredicate>
    inline bool
    equal(_IIter1 __first1, _IIter1 __last1,
	  _IIter2 __first2, _BinaryPredicate __binary_pred)
    {
      // concept requirements
      __glibcxx_function_requires(_InputIteratorConcept<_IIter1>)
      __glibcxx_function_requires(_InputIteratorConcept<_IIter2>)
      __glibcxx_requires_valid_range(__first1, __last1);

      for (; __first1 != __last1; ++__first1, ++__first2)
	if (!bool(__binary_pred(*__first1, *__first2)))
	  return false;
      return true;
    }

  /**
   *  @brief Performs "dictionary" comparison on ranges.
   *  @param  first1  An input iterator.
   *  @param  last1   An input iterator.
   *  @param  first2  An input iterator.
   *  @param  last2   An input iterator.
   *  @return   A boolean true or false.
   *
   *  "Returns true if the sequence of elements defined by the range
   *  [first1,last1) is lexicographically less than the sequence of elements
   *  defined by the range [first2,last2).  Returns false otherwise."
   *  (Quoted from [25.3.8]/1.)  If the iterators are all character pointers,
   *  then this is an inline call to @c memcmp.
  */
  template<typename _II1, typename _II2>
    inline bool
    lexicographical_compare(_II1 __first1, _II1 __last1,
			    _II2 __first2, _II2 __last2)
    {
      // concept requirements
      typedef typename iterator_traits<_II1>::value_type _ValueType1;
      typedef typename iterator_traits<_II2>::value_type _ValueType2;
      __glibcxx_function_requires(_InputIteratorConcept<_II1>)
      __glibcxx_function_requires(_InputIteratorConcept<_II2>)
      __glibcxx_function_requires(_LessThanOpConcept<_ValueType1, _ValueType2>)
      __glibcxx_function_requires(_LessThanOpConcept<_ValueType2, _ValueType1>)
      __glibcxx_requires_valid_range(__first1, __last1);
      __glibcxx_requires_valid_range(__first2, __last2);

      return std::__lexicographical_compare_aux
	(std::__niter_base<_II1>::__b(__first1),
	 std::__niter_base<_II1>::__b(__last1),
	 std::__niter_base<_II2>::__b(__first2),
	 std::__niter_base<_II2>::__b(__last2));
    }

  /**
   *  @brief Performs "dictionary" comparison on ranges.
   *  @param  first1  An input iterator.
   *  @param  last1   An input iterator.
   *  @param  first2  An input iterator.
   *  @param  last2   An input iterator.
   *  @param  comp  A @link s20_3_3_comparisons comparison functor@endlink.
   *  @return   A boolean true or false.
   *
   *  The same as the four-parameter @c lexicographical_compare, but uses the
   *  comp parameter instead of @c <.
  */
  template<typename _II1, typename _II2, typename _Compare>
    bool
    lexicographical_compare(_II1 __first1, _II1 __last1,
			    _II2 __first2, _II2 __last2, _Compare __comp)
    {
      typedef typename iterator_traits<_II1>::iterator_category _Category1;
      typedef typename iterator_traits<_II2>::iterator_category _Category2;
      typedef std::__lc_rai<_Category1, _Category2> 	__rai_type;

      // concept requirements
      __glibcxx_function_requires(_InputIteratorConcept<_II1>)
      __glibcxx_function_requires(_InputIteratorConcept<_II2>)
      __glibcxx_requires_valid_range(__first1, __last1);
      __glibcxx_requires_valid_range(__first2, __last2);

      __last1 = __rai_type::__newlast1(__first1, __last1, __first2, __last2);
      for (; __first1 != __last1 && __rai_type::__cnd2(__first2, __last2);
	   ++__first1, ++__first2)
	{
	  if (__comp(*__first1, *__first2))
	    return true;
	  if (__comp(*__first2, *__first1))
	    return false;
	}
      return __first1 == __last1 && __first2 != __last2;
    }

  /**
   *  @brief Finds the places in ranges which don't match.
   *  @param  first1  An input iterator.
   *  @param  last1   An input iterator.
   *  @param  first2  An input iterator.
   *  @return   A pair of iterators pointing to the first mismatch.
   *
   *  This compares the elements of two ranges using @c == and returns a pair
   *  of iterators.  The first iterator points into the first range, the
   *  second iterator points into the second range, and the elements pointed
   *  to by the iterators are not equal.
  */
  template<typename _InputIterator1, typename _InputIterator2>
    pair<_InputIterator1, _InputIterator2>
    mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
	     _InputIterator2 __first2)
    {
      // concept requirements
      __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
      __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
      __glibcxx_function_requires(_EqualOpConcept<
	    typename iterator_traits<_InputIterator1>::value_type,
	    typename iterator_traits<_InputIterator2>::value_type>)
      __glibcxx_requires_valid_range(__first1, __last1);

      while (__first1 != __last1 && *__first1 == *__first2)
        {
	  ++__first1;
	  ++__first2;
        }
      return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
    }

  /**
   *  @brief Finds the places in ranges which don't match.
   *  @param  first1  An input iterator.
   *  @param  last1   An input iterator.
   *  @param  first2  An input iterator.
   *  @param binary_pred A binary predicate @link s20_3_1_base
   *         functor@endlink.
   *  @return   A pair of iterators pointing to the first mismatch.
   *
   *  This compares the elements of two ranges using the binary_pred
   *  parameter, and returns a pair
   *  of iterators.  The first iterator points into the first range, the
   *  second iterator points into the second range, and the elements pointed
   *  to by the iterators are not equal.
  */
  template<typename _InputIterator1, typename _InputIterator2,
	   typename _BinaryPredicate>
    pair<_InputIterator1, _InputIterator2>
    mismatch(_InputIterator1 __first1, _InputIterator1 __last1,
	     _InputIterator2 __first2, _BinaryPredicate __binary_pred)
    {
      // concept requirements
      __glibcxx_function_requires(_InputIteratorConcept<_InputIterator1>)
      __glibcxx_function_requires(_InputIteratorConcept<_InputIterator2>)
      __glibcxx_requires_valid_range(__first1, __last1);

      while (__first1 != __last1 && bool(__binary_pred(*__first1, *__first2)))
        {
	  ++__first1;
	  ++__first2;
        }
      return pair<_InputIterator1, _InputIterator2>(__first1, __first2);
    }

_GLIBCXX_END_NESTED_NAMESPACE

// NB: This file is included within many other C++ includes, as a way
// of getting the base algorithms. So, make sure that parallel bits
// come in too if requested. 
#ifdef _GLIBCXX_PARALLEL
# include <parallel/algobase.h>
#endif

#endif
// Concept-checking control -*- C++ -*-

// Copyright (C) 2001 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.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/** @file concept_check.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 */

#ifndef _CONCEPT_CHECK_H
#define _CONCEPT_CHECK_H 1

#pragma GCC system_header

#include <bits/c++config.h>

// All places in libstdc++-v3 where these are used, or /might/ be used, or
// don't need to be used, or perhaps /should/ be used, are commented with
// "concept requirements" (and maybe some more text).  So grep like crazy
// if you're looking for additional places to use these.

// Concept-checking code is off by default unless users turn it on via
// configure options or editing c++config.h.

#ifndef _GLIBCXX_CONCEPT_CHECKS

#define __glibcxx_function_requires(...)
#define __glibcxx_class_requires(_a,_b)
#define __glibcxx_class_requires2(_a,_b,_c)
#define __glibcxx_class_requires3(_a,_b,_c,_d)
#define __glibcxx_class_requires4(_a,_b,_c,_d,_e)

#else // the checks are on

#include <bits/boost_concept_check.h>

// Note that the obvious and elegant approach of
//
//#define glibcxx_function_requires(C) boost::function_requires< boost::C >()
//
// won't work due to concept templates with more than one parameter, e.g.,
// BinaryPredicateConcept.  The preprocessor tries to split things up on
// the commas in the template argument list.  We can't use an inner pair of
// parenthesis to hide the commas, because "boost::(Temp<Foo,Bar>)" isn't
// a valid instantiation pattern.  Thus, we steal a feature from C99.

#define __glibcxx_function_requires(...)                                 \
            __gnu_cxx::__function_requires< __gnu_cxx::__VA_ARGS__ >();
#define __glibcxx_class_requires(_a,_C)                                  \
            _GLIBCXX_CLASS_REQUIRES(_a, __gnu_cxx, _C);
#define __glibcxx_class_requires2(_a,_b,_C)                              \
            _GLIBCXX_CLASS_REQUIRES2(_a, _b, __gnu_cxx, _C);
#define __glibcxx_class_requires3(_a,_b,_c,_C)                           \
            _GLIBCXX_CLASS_REQUIRES3(_a, _b, _c, __gnu_cxx, _C);
#define __glibcxx_class_requires4(_a,_b,_c,_d,_C)                        \
            _GLIBCXX_CLASS_REQUIRES4(_a, _b, _c, _d, __gnu_cxx, _C);

#endif // enable/disable

#endif // _GLIBCXX_CONCEPT_CHECK
// Iostreams base classes -*- C++ -*-

// Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
// 2006, 2007, 2008
// 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.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/** @file ios_base.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 */

//
// ISO C++ 14882: 27.4  Iostreams base classes
//

#ifndef _IOS_BASE_H
#define _IOS_BASE_H 1

#pragma GCC system_header

#include <ext/atomicity.h>
#include <bits/localefwd.h>
#include <bits/locale_classes.h>
#include <cstdio>  // For SEEK_CUR, SEEK_END

_GLIBCXX_BEGIN_NAMESPACE(std)

  // The following definitions of bitmask types are enums, not ints,
  // as permitted (but not required) in the standard, in order to provide
  // better type safety in iostream calls.  A side effect is that
  // expressions involving them are no longer compile-time constants.
  enum _Ios_Fmtflags 
    { 
      _S_boolalpha 	= 1L << 0,
      _S_dec 		= 1L << 1,
      _S_fixed 		= 1L << 2,
      _S_hex 		= 1L << 3,
      _S_internal 	= 1L << 4,
      _S_left 		= 1L << 5,
      _S_oct 		= 1L << 6,
      _S_right 		= 1L << 7,
      _S_scientific 	= 1L << 8,
      _S_showbase 	= 1L << 9,
      _S_showpoint 	= 1L << 10,
      _S_showpos 	= 1L << 11,
      _S_skipws 	= 1L << 12,
      _S_unitbuf 	= 1L << 13,
      _S_uppercase 	= 1L << 14,
      _S_adjustfield 	= _S_left | _S_right | _S_internal,
      _S_basefield 	= _S_dec | _S_oct | _S_hex,
      _S_floatfield 	= _S_scientific | _S_fixed,
      _S_ios_fmtflags_end = 1L << 16 
    };

  inline _Ios_Fmtflags
  operator&(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
  { return _Ios_Fmtflags(static_cast<int>(__a) & static_cast<int>(__b)); }

  inline _Ios_Fmtflags
  operator|(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
  { return _Ios_Fmtflags(static_cast<int>(__a) | static_cast<int>(__b)); }

  inline _Ios_Fmtflags
  operator^(_Ios_Fmtflags __a, _Ios_Fmtflags __b)
  { return _Ios_Fmtflags(static_cast<int>(__a) ^ static_cast<int>(__b)); }

  inline _Ios_Fmtflags&
  operator|=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
  { return __a = __a | __b; }

  inline _Ios_Fmtflags&
  operator&=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
  { return __a = __a & __b; }

  inline _Ios_Fmtflags&
  operator^=(_Ios_Fmtflags& __a, _Ios_Fmtflags __b)
  { return __a = __a ^ __b; }

  inline _Ios_Fmtflags
  operator~(_Ios_Fmtflags __a)
  { return _Ios_Fmtflags(~static_cast<int>(__a)); }


  enum _Ios_Openmode 
    { 
      _S_app 		= 1L << 0,
      _S_ate 		= 1L << 1,
      _S_bin 		= 1L << 2,
      _S_in 		= 1L << 3,
      _S_out 		= 1L << 4,
      _S_trunc 		= 1L << 5,
      _S_ios_openmode_end = 1L << 16 
    };

  inline _Ios_Openmode
  operator&(_Ios_Openmode __a, _Ios_Openmode __b)
  { return _Ios_Openmode(static_cast<int>(__a) & static_cast<int>(__b)); }

  inline _Ios_Openmode
  operator|(_Ios_Openmode __a, _Ios_Openmode __b)
  { return _Ios_Openmode(static_cast<int>(__a) | static_cast<int>(__b)); }

  inline _Ios_Openmode
  operator^(_Ios_Openmode __a, _Ios_Openmode __b)
  { return _Ios_Openmode(static_cast<int>(__a) ^ static_cast<int>(__b)); }

  inline _Ios_Openmode&
  operator|=(_Ios_Openmode& __a, _Ios_Openmode __b)
  { return __a = __a | __b; }

  inline _Ios_Openmode&
  operator&=(_Ios_Openmode& __a, _Ios_Openmode __b)
  { return __a = __a & __b; }

  inline _Ios_Openmode&
  operator^=(_Ios_Openmode& __a, _Ios_Openmode __b)
  { return __a = __a ^ __b; }

  inline _Ios_Openmode
  operator~(_Ios_Openmode __a)
  { return _Ios_Openmode(~static_cast<int>(__a)); }


  enum _Ios_Iostate
    { 
      _S_goodbit 		= 0,
      _S_badbit 		= 1L << 0,
      _S_eofbit 		= 1L << 1,
      _S_failbit		= 1L << 2,
      _S_ios_iostate_end = 1L << 16 
    };

  inline _Ios_Iostate
  operator&(_Ios_Iostate __a, _Ios_Iostate __b)
  { return _Ios_Iostate(static_cast<int>(__a) & static_cast<int>(__b)); }

  inline _Ios_Iostate
  operator|(_Ios_Iostate __a, _Ios_Iostate __b)
  { return _Ios_Iostate(static_cast<int>(__a) | static_cast<int>(__b)); }

  inline _Ios_Iostate
  operator^(_Ios_Iostate __a, _Ios_Iostate __b)
  { return _Ios_Iostate(static_cast<int>(__a) ^ static_cast<int>(__b)); }

  inline _Ios_Iostate&
  operator|=(_Ios_Iostate& __a, _Ios_Iostate __b)
  { return __a = __a | __b; }

  inline _Ios_Iostate&
  operator&=(_Ios_Iostate& __a, _Ios_Iostate __b)
  { return __a = __a & __b; }

  inline _Ios_Iostate&
  operator^=(_Ios_Iostate& __a, _Ios_Iostate __b)
  { return __a = __a ^ __b; }

  inline _Ios_Iostate
  operator~(_Ios_Iostate __a)
  { return _Ios_Iostate(~static_cast<int>(__a)); }

  enum _Ios_Seekdir 
    { 
      _S_beg = 0,
      _S_cur = SEEK_CUR,
      _S_end = SEEK_END,
      _S_ios_seekdir_end = 1L << 16 
    };

  // 27.4.2  Class ios_base
  /**
   *  @brief  The base of the I/O class hierarchy.
   *
   *  This class defines everything that can be defined about I/O that does
   *  not depend on the type of characters being input or output.  Most
   *  people will only see @c ios_base when they need to specify the full
   *  name of the various I/O flags (e.g., the openmodes).
  */
  class ios_base
  {
  public:

    // 27.4.2.1.1  Class ios_base::failure
    /// These are thrown to indicate problems.  Doc me.
    class failure : public exception
    {
    public:
      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 48.  Use of non-existent exception constructor
      explicit
      failure(const string& __str) throw();

      // This declaration is not useless:
      // http://gcc.gnu.org/onlinedocs/gcc-4.3.2/gcc/Vague-Linkage.html
      virtual
      ~failure() throw();

      virtual const char*
      what() const throw();

    private:
      string _M_msg;
    };

    // 27.4.2.1.2  Type ios_base::fmtflags
    /**
     *  @brief This is a bitmask type.
     *
     *  @c "_Ios_Fmtflags" is implementation-defined, but it is valid to
     *  perform bitwise operations on these values and expect the Right
     *  Thing to happen.  Defined objects of type fmtflags are:
     *  - boolalpha
     *  - dec
     *  - fixed
     *  - hex
     *  - internal
     *  - left
     *  - oct
     *  - right
     *  - scientific
     *  - showbase
     *  - showpoint
     *  - showpos
     *  - skipws
     *  - unitbuf
     *  - uppercase
     *  - adjustfield
     *  - basefield
     *  - floatfield
    */
    typedef _Ios_Fmtflags fmtflags;

    /// Insert/extract @c bool in alphabetic rather than numeric format.
    static const fmtflags boolalpha =   _S_boolalpha;

    /// Converts integer input or generates integer output in decimal base.
    static const fmtflags dec =         _S_dec;

    /// Generate floating-point output in fixed-point notation.
    static const fmtflags fixed =       _S_fixed;

    /// Converts integer input or generates integer output in hexadecimal base.
    static const fmtflags hex =         _S_hex;

    /// Adds fill characters at a designated internal point in certain
    /// generated output, or identical to @c right if no such point is
    /// designated.
    static const fmtflags internal =    _S_internal;

    /// Adds fill characters on the right (final positions) of certain
    /// generated output.  (I.e., the thing you print is flush left.)
    static const fmtflags left =        _S_left;

    /// Converts integer input or generates integer output in octal base.
    static const fmtflags oct =         _S_oct;

    /// Adds fill characters on the left (initial positions) of certain
    /// generated output.  (I.e., the thing you print is flush right.)
    static const fmtflags right =       _S_right;

    /// Generates floating-point output in scientific notation.
    static const fmtflags scientific =  _S_scientific;

    /// Generates a prefix indicating the numeric base of generated integer
    /// output.
    static const fmtflags showbase =    _S_showbase;

    /// Generates a decimal-point character unconditionally in generated
    /// floating-point output.
    static const fmtflags showpoint =   _S_showpoint;

    /// Generates a + sign in non-negative generated numeric output.
    static const fmtflags showpos =     _S_showpos;

    /// Skips leading white space before certain input operations.
    static const fmtflags skipws =      _S_skipws;

    /// Flushes output after each output operation.
    static const fmtflags unitbuf =     _S_unitbuf;

    /// Replaces certain lowercase letters with their uppercase equivalents
    /// in generated output.
    static const fmtflags uppercase =   _S_uppercase;

    /// A mask of left|right|internal.  Useful for the 2-arg form of @c setf.
    static const fmtflags adjustfield = _S_adjustfield;

    /// A mask of dec|oct|hex.  Useful for the 2-arg form of @c setf.
    static const fmtflags basefield =   _S_basefield;

    /// A mask of scientific|fixed.  Useful for the 2-arg form of @c setf.
    static const fmtflags floatfield =  _S_floatfield;

    // 27.4.2.1.3  Type ios_base::iostate
    /**
     *  @brief This is a bitmask type.
     *
     *  @c "_Ios_Iostate" is implementation-defined, but it is valid to
     *  perform bitwise operations on these values and expect the Right
     *  Thing to happen.  Defined objects of type iostate are:
     *  - badbit
     *  - eofbit
     *  - failbit
     *  - goodbit
    */
    typedef _Ios_Iostate iostate;

    /// Indicates a loss of integrity in an input or output sequence (such
    /// as an irrecoverable read error from a file).
    static const iostate badbit =	_S_badbit;

    /// Indicates that an input operation reached the end of an input sequence.
    static const iostate eofbit =	_S_eofbit;

    /// Indicates that an input operation failed to read the expected
    /// characters, or that an output operation failed to generate the
    /// desired characters.
    static const iostate failbit =	_S_failbit;

    /// Indicates all is well.
    static const iostate goodbit =	_S_goodbit;

    // 27.4.2.1.4  Type ios_base::openmode
    /**
     *  @brief This is a bitmask type.
     *
     *  @c "_Ios_Openmode" is implementation-defined, but it is valid to
     *  perform bitwise operations on these values and expect the Right
     *  Thing to happen.  Defined objects of type openmode are:
     *  - app
     *  - ate
     *  - binary
     *  - in
     *  - out
     *  - trunc
    */
    typedef _Ios_Openmode openmode;

    /// Seek to end before each write.
    static const openmode app =		_S_app;

    /// Open and seek to end immediately after opening.
    static const openmode ate =		_S_ate;

    /// Perform input and output in binary mode (as opposed to text mode).
    /// This is probably not what you think it is; see
    /// http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch27s02.html
    static const openmode binary =	_S_bin;

    /// Open for input.  Default for @c ifstream and fstream.
    static const openmode in =		_S_in;

    /// Open for output.  Default for @c ofstream and fstream.
    static const openmode ou",#,$,%,&,',(,),*,+,,,-,.,/,0,1,t =		_S_out;

    /// Open for input.  Default for @c ofstream.
    static const openmode trunc =	_S_trunc;

    // 27.4.2.1.5  Type ios_base::seekdir
    /**
     *  @brief This is an enumerated type.
     *
     *  @c "_Ios_Seekdir" is implementation-defined.  Defined values
     *  of type seekdir are:
     *  - beg
     *  - cur, equivalent to @c SEEK_CUR in the C standard library.
     *  - end, equivalent to @c SEEK_END in the C standard library.
    */
    typedef _Ios_Seekdir seekdir;

    /// Request a seek relative to the beginning of the stream.
    static const seekdir beg =		_S_beg;

    /// Request a seek relative to the current position within the sequence.
    static const seekdir cur =		_S_cur;

    /// Request a seek relative to the current end of the sequence.
    static const seekdir end =		_S_end;

    // Annex D.6
    typedef int io_state;
    typedef int open_mode;
    typedef int seek_dir;

    typedef std::streampos streampos;
    typedef std::streamoff streamoff;

    // Callbacks;
    /**
     *  @brief  The set of events that may be passed to an event callback.
     *
     *  erase_event is used during ~ios() and copyfmt().  imbue_event is used
     *  during imbue().  copyfmt_event is used during copyfmt().
    */
    enum event
    {
      erase_event,
      imbue_event,
      copyfmt_event
    };

    /**
     *  @brief  The type of an event callback function.
     *  @param  event  One of the members of the event enum.
     *  @param  ios_base  Reference to the ios_base object.
     *  @param  int  The integer provided when the callback was registered.
     *
     *  Event callbacks are user defined functions that get called during
     *  several ios_base and basic_ios functions, specifically imbue(),
     *  copyfmt(), and ~ios().
    */
    typedef void (*event_callback) (event, ios_base&, int);

    /**
     *  @brief  Add the callback __fn with parameter __index.
     *  @param  __fn  The function to add.
     *  @param  __index  The integer to pass to the function when invoked.
     *
     *  Registers a function as an event callback with an integer parameter to
     *  be passed to the function when invoked.  Multiple copies of the
     *  function are allowed.  If there are multiple callbacks, they are
     *  invoked in the order they were registered.
    */
    void
    register_callback(event_callback __fn, int __index);

  protected:
    //@{
    /**
     *  ios_base data members (doc me)
    */
    streamsize		_M_precision;
    streamsize		_M_width;
    fmtflags		_M_flags;
    iostate		_M_exception;
    iostate		_M_streambuf_state;
    //@}

    // 27.4.2.6  Members for callbacks
    // 27.4.2.6  ios_base callbacks
    struct _Callback_list
    {
      // Data Members
      _Callback_list*		_M_next;
      ios_base::event_callback	_M_fn;
      int			_M_index;
      _Atomic_word		_M_refcount;  // 0 means one reference.

      _Callback_list(ios_base::event_callback __fn, int __index,
		     _Callback_list* __cb)
      : _M_next(__cb), _M_fn(__fn), _M_index(__index), _M_refcount(0) { }

      void
      _M_add_reference() { __gnu_cxx::__atomic_add_dispatch(&_M_refcount, 1); }

      // 0 => OK to delete.
      int
      _M_remove_reference() 
      { return __gnu_cxx::__exchange_and_add_dispatch(&_M_refcount, -1); }
    };

     _Callback_list*	_M_callbacks;

    void
    _M_call_callbacks(event __ev) throw();

    void
    _M_dispose_callbacks(void);

    // 27.4.2.5  Members for iword/pword storage
    struct _Words
    {
      void*	_M_pword;
      long	_M_iword;
      _Words() : _M_pword(0), _M_iword(0) { }
    };

    // Only for failed iword/pword calls.
    _Words		_M_word_zero;

    // Guaranteed storage.
    // The first 5 iword and pword slots are reserved for internal use.
    enum { _S_local_word_size = 8 };
    _Words		_M_local_word[_S_local_word_size];

    // Allocated storage.
    int			_M_word_size;
    _Words*		_M_word;

    _Words&
    _M_grow_words(int __index, bool __iword);

    // Members for locale and locale caching.
    locale		_M_ios_locale;

    void
    _M_init();

  public:

    // 27.4.2.1.6  Class ios_base::Init
    // Used to initialize standard streams. In theory, g++ could use
    // -finit-priority to order this stuff correctly without going
    // through these machinations.
    class Init
    {
      friend class ios_base;
    public:
      Init();
      ~Init();

    private:
      static _Atomic_word	_S_refcount;
      static bool		_S_synced_with_stdio;
    };

    // [27.4.2.2] fmtflags state functions
    /**
     *  @brief  Access to format flags.
     *  @return  The format control flags for both input and output.
    */
    fmtflags
    flags() const
    { return _M_flags; }

    /**
     *  @brief  Setting new format flags all at once.
     *  @param  fmtfl  The new flags to set.
     *  @return  The previous format control flags.
     *
     *  This function overwrites all the format flags with @a fmtfl.
    */
    fmtflags
    flags(fmtflags __fmtfl)
    {
      fmtflags __old = _M_flags;
      _M_flags = __fmtfl;
      return __old;
    }

    /**
     *  @brief  Setting new format flags.
     *  @param  fmtfl  Additional flags to set.
     *  @return  The previous format control flags.
     *
     *  This function sets additional flags in format control.  Flags that
     *  were previously set remain set.
    */
    fmtflags
    setf(fmtflags __fmtfl)
    {
      fmtflags __old = _M_flags;
      _M_flags |= __fmtfl;
      return __old;
    }

    /**
     *  @brief  Setting new format flags.
     *  @param  fmtfl  Additional flags to set.
     *  @param  mask  The flags mask for @a fmtfl.
     *  @return  The previous format control flags.
     *
     *  This function clears @a mask in the format flags, then sets
     *  @a fmtfl @c & @a mask.  An example mask is @c ios_base::adjustfield.
    */
    fmtflags
    setf(fmtflags __fmtfl, fmtflags __mask)
    {
      fmtflags __old = _M_flags;
      _M_flags &= ~__mask;
      _M_flags |= (__fmtfl & __mask);
      return __old;
    }

    /**
     *  @brief  Clearing format flags.
     *  @param  mask  The flags to unset.
     *
     *  This function clears @a mask in the format flags.
    */
    void
    unsetf(fmtflags __mask)
    { _M_flags &= ~__mask; }

    /**
     *  @brief  Flags access.
     *  @return  The precision to generate on certain output operations.
     *
     *  Be careful if you try to give a definition of "precision" here; see
     *  DR 189.
    */
    streamsize
    precision() const
    { return _M_precision; }

    /**
     *  @brief  Changing flags.
     *  @param  prec  The new precision value.
     *  @return  The previous value of precision().
    */
    streamsize
    precision(streamsize __prec)
    {
      streamsize __old = _M_precision;
      _M_precision = __prec;
      return __old;
    }

    /**
     *  @brief  Flags access.
     *  @return  The minimum field width to generate on output operations.
     *
     *  "Minimum field width" refers to the number of characters.
    */
    streamsize
    width() const
    { return _M_width; }

    /**
     *  @brief  Changing flags.
     *  @param  wide  The new width value.
     *  @return  The previous value of width().
    */
    streamsize
    width(streamsize __wide)
    {
      streamsize __old = _M_width;
      _M_width = __wide;
      return __old;
    }

    // [27.4.2.4] ios_base static members
    /**
     *  @brief  Interaction with the standard C I/O objects.
     *  @param  sync  Whether to synchronize or not.
     *  @return  True if the standard streams were previously synchronized.
     *
     *  The synchronization referred to is @e only that between the standard
     *  C facilities (e.g., stdout) and the standard C++ objects (e.g.,
     *  cout).  User-declared streams are unaffected.  See
     *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt11ch28s02.html
    */
    static bool
    sync_with_stdio(bool __sync = true);

    // [27.4.2.3] ios_base locale functions
    /**
     *  @brief  Setting a new locale.
     *  @param  loc  The new locale.
     *  @return  The previous locale.
     *
     *  Sets the new locale for this stream, and then invokes each callback
     *  with imbue_event.
    */
    locale
    imbue(const locale& __loc);

    /**
     *  @brief  Locale access
     *  @return  A copy of the current locale.
     *
     *  If @c imbue(loc) has previously been called, then this function
     *  returns @c loc.  Otherwise, it returns a copy of @c std::locale(),
     *  the global C++ locale.
    */
    locale
    getloc() const
    { return _M_ios_locale; }

    /**
     *  @brief  Locale access
     *  @return  A reference to the current locale.
     *
     *  Like getloc above, but returns a reference instead of
     *  generating a copy.
    */
    const locale&
    _M_getloc() const
    { return _M_ios_locale; }

    // [27.4.2.5] ios_base storage functions
    /**
     *  @brief  Access to unique indices.
     *  @return  An integer different from all previous calls.
     *
     *  This function returns a unique integer every time it is called.  It
     *  can be used for any purpose, but is primarily intended to be a unique
     *  index for the iword and pword functions.  The expectation is that an
     *  application calls xalloc in order to obtain an index in the iword and
     *  pword arrays that can be used without fear of conflict.
     *
     *  The implementation maintains a static variable that is incremented and
     *  returned on each invocation.  xalloc is guaranteed to return an index
     *  that is safe to use in the iword and pword arrays.
    */
    static int
    xalloc() throw();

    /**
     *  @brief  Access to integer array.
     *  @param  __ix  Index into the array.
     *  @return  A reference to an integer associated with the index.
     *
     *  The iword function provides access to an array of integers that can be
     *  used for any purpose.  The array grows as required to hold the
     *  supplied index.  All integers in the array are initialized to 0.
     *
     *  The implementation reserves several indices.  You should use xalloc to
     *  obtain an index that is safe to use.  Also note that since the array
     *  can grow dynamically, it is not safe to hold onto the reference.
    */
    long&
    iword(int __ix)
    {
      _Words& __word = (__ix < _M_word_size)
			? _M_word[__ix] : _M_grow_words(__ix, true);
      return __word._M_iword;
    }

    /**
     *  @brief  Access to void pointer array.
     *  @param  __ix  Index into the array.
     *  @return  A reference to a void* associated with the index.
     *
     *  The pword function provides access to an array of pointers that can be
     *  used for any purpose.  The array grows as required to hold the
     *  supplied index.  All pointers in the array are initialized to 0.
     *
     *  The implementation reserves several indices.  You should use xalloc to
     *  obtain an index that is safe to use.  Also note that since the array
     *  can grow dynamically, it is not safe to hold onto the reference.
    */
    void*&
    pword(int __ix)
    {
      _Words& __word = (__ix < _M_word_size)
			? _M_word[__ix] : _M_grow_words(__ix, false);
      return __word._M_pword;
    }

    // Destructor
    /**
     *  Invokes each callback with erase_event.  Destroys local storage.
     *
     *  Note that the ios_base object for the standard streams never gets
     *  destroyed.  As a result, any callbacks registered with the standard
     *  streams will not get invoked with erase_event (unless copyfmt is
     *  used).
    */
    virtual ~ios_base();

  protected:
    ios_base();

  // _GLIBCXX_RESOLVE_LIB_DEFECTS
  // 50.  Copy constructor and assignment operator of ios_base
  private:
    ios_base(const ios_base&);

    ios_base&
    operator=(const ios_base&);
  };

  // [27.4.5.1] fmtflags manipulators
  /// Calls base.setf(ios_base::boolalpha).
  inline ios_base&
  boolalpha(ios_base& __base)
  {
    __base.setf(ios_base::boolalpha);
    return __base;
  }

  /// Calls base.unsetf(ios_base::boolalpha).
  inline ios_base&
  noboolalpha(ios_base& __base)
  {
    __base.unsetf(ios_base::boolalpha);
    return __base;
  }

  /// Calls base.setf(ios_base::showbase).
  inline ios_base&
  showbase(ios_base& __base)
  {
    __base.setf(ios_base::showbase);
    return __base;
  }

  /// Calls base.unsetf(ios_base::showbase).
  inline ios_base&
  noshowbase(ios_base& __base)
  {
    __base.unsetf(ios_base::showbase);
    return __base;
  }

  /// Calls base.setf(ios_base::showpoint).
  inline ios_base&
  showpoint(ios_base& __base)
  {
    __base.setf(ios_base::showpoint);
    return __base;
  }

  /// Calls base.unsetf(ios_base::showpoint).
  inline ios_base&
  noshowpoint(ios_base& __base)
  {
    __base.unsetf(ios_base::showpoint);
    return __base;
  }

  /// Calls base.setf(ios_base::showpos).
  inline ios_base&
  showpos(ios_base& __base)
  {
    __base.setf(ios_base::showpos);
    return __base;
  }

  /// Calls base.unsetf(ios_base::showpos).
  inline ios_base&
  noshowpos(ios_base& __base)
  {
    __base.unsetf(ios_base::showpos);
    return __base;
  }

  /// Calls base.setf(ios_base::skipws).
  inline ios_base&
  skipws(ios_base& __base)
  {
    __base.setf(ios_base::skipws);
    return __base;
  }

  /// Calls base.unsetf(ios_base::skipws).
  inline ios_base&
  noskipws(ios_base& __base)
  {
    __base.unsetf(ios_base::skipws);
    return __base;
  }

  /// Calls base.setf(ios_base::uppercase).
  inline ios_base&
  uppercase(ios_base& __base)
  {
    __base.setf(ios_base::uppercase);
    return __base;
  }

  /// Calls base.unsetf(ios_base::uppercase).
  inline ios_base&
  nouppercase(ios_base& __base)
  {
    __base.unsetf(ios_base::uppercase);
    return __base;
  }

  /// Calls base.setf(ios_base::unitbuf).
  inline ios_base&
  unitbuf(ios_base& __base)
  {
     __base.setf(ios_base::unitbuf);
     return __base;
  }

  /// Calls base.unsetf(ios_base::unitbuf).
  inline ios_base&
  nounitbuf(ios_base& __base)
  {
     __base.unsetf(ios_base::unitbuf);
     return __base;
  }

  // [27.4.5.2] adjustfield manipulators
  /// Calls base.setf(ios_base::internal, ios_base::adjustfield).
  inline ios_base&
  internal(ios_base& __base)
  {
     __base.setf(ios_base::internal, ios_base::adjustfield);
     return __base;
  }

  /// Calls base.setf(ios_base::left, ios_base::adjustfield).
  inline ios_base&
  left(ios_base& __base)
  {
    __base.setf(ios_base::left, ios_base::adjustfield);
    return __base;
  }

  /// Calls base.setf(ios_base::right, ios_base::adjustfield).
  inline ios_base&
  right(ios_base& __base)
  {
    __base.setf(ios_base::right, ios_base::adjustfield);
    return __base;
  }

  // [27.4.5.3] basefield manipulators
  /// Calls base.setf(ios_base::dec, ios_base::basefield).
  inline ios_base&
  dec(ios_base& __base)
  {
    __base.setf(ios_base::dec, ios_base::basefield);
    return __base;
  }

  /// Calls base.setf(ios_base::hex, ios_base::basefield).
  inline ios_base&
  hex(ios_base& __base)
  {
    __base.setf(ios_base::hex, ios_base::basefield);
    return __base;
  }

  /// Calls base.setf(ios_base::oct, ios_base::basefield).
  inline ios_base&
  oct(ios_base& __base)
  {
    __base.setf(ios_base::oct, ios_base::basefield);
    return __base;
  }

  // [27.4.5.4] floatfield manipulators
  /// Calls base.setf(ios_base::fixed, ios_base::floatfield).
  inline ios_base&
  fixed(ios_base& __base)
  {
    __base.setf(ios_base::fixed, ios_base::floatfield);
    return __base;
  }

  /// Calls base.setf(ios_base::scientific, ios_base::floatfield).
  inline ios_base&
  scientific(ios_base& __base)
  {
    __base.setf(ios_base::scientific, ios_base::floatfield);
    return __base;
  }

_GLIBCXX_END_NAMESPACE

#endif /* _IOS_BASE_H */

// Types used in iterator implementation -*- C++ -*-

// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
// 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.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996-1998
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

/** @file stl_iterator_base_types.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 *
 *  This file contains all of the general iterator-related utility types,
 *  such as iterator_traits and struct iterator.
 */

#ifndef _STL_ITERATOR_BASE_TYPES_H
#define _STL_ITERATOR_BASE_TYPES_H 1

#pragma GCC system_header

#include <bits/c++config.h>
#include <cstddef>

_GLIBCXX_BEGIN_NAMESPACE(std)

  //@{
  /**
   *  @defgroup iterator_tags Iterator Tags
   *  These are empty types, used to distinguish different iterators.  The
   *  distinction is not made by what they contain, but simply by what they
   *  are.  Different underlying algorithms can then be used based on the
   *  different operations supported by different iterator types.
  */
  ///  Marking input iterators.
  struct input_iterator_tag {};
  ///  Marking output iterators.
  struct output_iterator_tag {};
  /// Forward iterators support a superset of input iterator operations.
  struct forward_iterator_tag : public input_iterator_tag {};
  /// Bidirectional iterators support a superset of forward iterator
  /// operations.
  struct bidirectional_iterator_tag : public forward_iterator_tag {};
  /// Random-access iterators support a superset of bidirectional iterator
  /// operations.
  struct random_access_iterator_tag : public bidirectional_iterator_tag {};
  //@}


  /**
   *  @brief  Common %iterator class.
   *
   *  This class does nothing but define nested typedefs.  %Iterator classes
   *  can inherit from this class to save some work.  The typedefs are then
   *  used in specializations and overloading.
   *
   *  In particular, there are no default implementations of requirements
   *  such as @c operator++ and the like.  (How could there be?)
  */
  template<typename _Category, typename _Tp, typename _Distance = ptrdiff_t,
           typename _Pointer = _Tp*, typename _Reference = _Tp&>
    struct iterator
    {
      /// One of the @link iterator_tags tag types@endlink.
      typedef _Category  iterator_category;
      /// The type "pointed to" by the iterator.
      typedef _Tp        value_type;
      /// Distance between iterators is represented as this type.
      typedef _Distance  difference_type;
      /// This type represents a pointer-to-value_type.
      typedef _Pointer   pointer;
      /// This type represents a reference-to-value_type.
      typedef _Reference reference;
    };

  /**
   *  This class does nothing but define nested typedefs.  The general
   *  version simply "forwards" the nested typedefs from the Iterator
   *  argument.  Specialized versions for pointers and pointers-to-const
   *  provide tighter, more correct semantics.
  */
  template<typename _Iterator>
    struct iterator_traits
    {
      typedef typename _Iterator::iterator_category iterator_category;
      typedef typename _Iterator::value_type        value_type;
      typedef typename _Iterator::difference_type   difference_type;
      typedef typename _Iterator::pointer           pointer;
      typedef typename _Iterator::reference         reference;
    };

  template<typename _Tp>
    struct iterator_traits<_Tp*>
    {
      typedef random_access_iterator_tag iterator_category;
      typedef _Tp                         value_type;
      typedef ptrdiff_t                   difference_type;
      typedef _Tp*                        pointer;
      typedef _Tp&                        reference;
    };

  template<typename _Tp>
    struct iterator_traits<const _Tp*>
    {
      typedef random_access_iterator_tag iterator_category;
      typedef _Tp                         value_type;
      typedef ptrdiff_t                   difference_type;
      typedef const _Tp*                  pointer;
      typedef const _Tp&                  reference;
    };

  /**
   *  This function is not a part of the C++ standard but is syntactic
   *  sugar for internal library use only.
  */
  template<typename _Iter>
    inline typename iterator_traits<_Iter>::iterator_category
    __iterator_category(const _Iter&)
    { return typename iterator_traits<_Iter>::iterator_category(); }

_GLIBCXX_END_NAMESPACE

#endif /* _STL_ITERATOR_BASE_TYPES_H */

// Iterators -*- C++ -*-

// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
// 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.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

/*
 *
 * Copyright (c) 1994
 * Hewlett-Packard Company
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Hewlett-Packard Company makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 *
 *
 * Copyright (c) 1996-1998
 * Silicon Graphics Computer Systems, Inc.
 *
 * Permission to use, copy, modify, distribute and sell this software
 * and its documentation for any purpose is hereby granted without fee,
 * provided that the above copyright notice appear in all copies and
 * that both that copyright notice and this permission notice appear
 * in supporting documentation.  Silicon Graphics makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied warranty.
 */

/** @file stl_iterator.h
 *  This is an internal header file, included by other library headers.
 *  You should not attempt to use it directly.
 *
 *  This file implements reverse_iterator, back_insert_iterator,
 *  front_insert_iterator, insert_iterator, __normal_iterator, and their
 *  supporting functions and overloaded operators.
 */

#ifndef _STL_ITERATOR_H
#define _STL_ITERATOR_H 1

#include <bits/cpp_type_traits.h>
#include <ext/type_traits.h>
#include <bits/stl_move.h>

_GLIBCXX_BEGIN_NAMESPACE(std)

  // 24.4.1 Reverse iterators
  /**
   *  "Bidirectional and random access iterators have corresponding reverse
   *  %iterator adaptors that iterate through the data structure in the
   *  opposite direction.  They have the same signatures as the corresponding
   *  iterators.  The fundamental relation between a reverse %iterator and its
   *  corresponding %iterator @c i is established by the identity:
   *  @code
   *      &*(reverse_iterator(i)) == &*(i - 1)
   *  @endcode
   *
   *  This mapping is dictated by the fact that while there is always a
   *  pointer past the end of an array, there might not be a valid pointer
   *  before the beginning of an array." [24.4.1]/1,2
   *
   *  Reverse iterators can be tricky and surprising at first.  Their
   *  semantics make sense, however, and the trickiness is a side effect of
   *  the requirement that the iterators must be safe.
  */
  template<typename _Iterator>
    class reverse_iterator
    : public iterator<typename iterator_traits<_Iterator>::iterator_category,
		      typename iterator_traits<_Iterator>::value_type,
		      typename iterator_traits<_Iterator>::difference_type,
		      typename iterator_traits<_Iterator>::pointer,
                      typename iterator_traits<_Iterator>::reference>
    {
    protected:
      _Iterator current;

    public:
      typedef _Iterator					       iterator_type;
      typedef typename iterator_traits<_Iterator>::difference_type
							       difference_type;
      typedef typename iterator_traits<_Iterator>::reference   reference;
      typedef typename iterator_traits<_Iterator>::pointer     pointer;

    public:
      /**
       *  The default constructor default-initializes member @p current.
       *  If it is a pointer, that means it is zero-initialized.
      */
      // _GLIBCXX_RESOLVE_LIB_DEFECTS
      // 235 No specification of default ctor for reverse_iterator
      reverse_iterator() : current() { }

      /**
       *  This %iterator will move in the opposite direction that @p x does.
      */
      explicit
      reverse_iterator(iterator_type __x) : current(__x) { }

      /**
       *  The copy constructor is normal.
      */
      reverse_iterator(const reverse_iterator& __x)
      : current(__x.current) { }

      /**
       *  A reverse_iterator across other types can be copied in the normal
       *  fashion.
      */
      template<typename _Iter>
        reverse_iterator(const reverse_iterator<_Iter>& __x)
	: current(__x.base()) { }

      /**
       *  @return  @c current, the %iterator used for underlying work.
      */
      iterator_type
      base() const
      { return current; }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reference
      operator*() const
      {
	_Iterator __tmp = current;
	return *--__tmp;
      }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      pointer
      operator->() const
      { return &(operator*()); }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reverse_iterator&
      operator++()
      {
	--current;
	return *this;
      }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reverse_iterator
      operator++(int)
      {
	reverse_iterator __tmp = *this;
	--current;
	return __tmp;
      }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reverse_iterator&
      operator--()
      {
	++current;
	return *this;
      }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reverse_iterator
      operator--(int)
      {
	reverse_iterator __tmp = *this;
	++current;
	return __tmp;
      }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reverse_iterator
      operator+(difference_type __n) const
      { return reverse_iterator(current - __n); }

      /**
       *  @return  TODO
       *
       *  @doctodo
      */
      reverse_iterator&
      operator+=(difference_type __n)
      {
	current -= __n;
	return *this;
      }

      /**
       *  @return  TODO
       *