iterator

// iterator standard header
#pragma once
#ifndef _ITERATOR_
#define _ITERATOR_
#ifndef RC_INVOKED
#include <istream>
#include <xutility>

 #pragma pack(push,_CRT_PACKING)
 #pragma warning(push,3)
 #pragma push_macro("new")
 #undef new

_STD_BEGIN
		// TEMPLATE CLASS back_insert_iterator
template<class _Container>
	class back_insert_iterator
		: public _Outit
	{	// wrap pushes to back of container as output iterator
public:
	typedef back_insert_iterator<_Container> _Myt;
	typedef _Container container_type;
	typedef typename _Container::value_type _Valty;

	explicit back_insert_iterator(_Container& _Cont)
		: container(_STD addressof(_Cont))
		{	// construct with container
		}

	_Myt& operator=(const _Valty& _Val)
		{	// push value into container
		container->push_back(_Val);
		return (*this);
		}

	_Myt& operator=(_Valty&& _Val)
		{	// push value into container
		container->push_back(_STD forward<_Valty>(_Val));
		return (*this);
		}

	_Myt& operator*()
		{	// pretend to return designated value
		return (*this);
		}

	_Myt& operator++()
		{	// pretend to preincrement
		return (*this);
		}

	_Myt operator++(int)
		{	// pretend to postincrement
		return (*this);
		}

protected:
	_Container *container;	// pointer to container
	};

template<class _Container>
	struct _Is_checked_helper<back_insert_iterator<_Container> >
		: public true_type
	{	// mark back_insert_iterator as checked
	};

		// TEMPLATE FUNCTION back_inserter
template<class _Container> inline
	back_insert_iterator<_Container> back_inserter(_Container& _Cont)
	{	// return a back_insert_iterator
	return (back_insert_iterator<_Container>(_Cont));
	}

		// TEMPLATE CLASS front_insert_iterator
template<class _Container>
	class front_insert_iterator
		: public _Outit
	{	// wrap pushes to front of container as output iterator
public:
	typedef front_insert_iterator<_Container> _Myt;
	typedef _Container container_type;
	typedef typename _Container::value_type _Valty;

	explicit front_insert_iterator(_Container& _Cont)
		: container(_STD addressof(_Cont))
		{	// construct with container
		}

	_Myt& operator=(const _Valty& _Val)
		{	// push value into container
		container->push_front(_Val);
		return (*this);
		}

	_Myt& operator=(_Valty&& _Val)
		{	// push value into container
		container->push_front(_STD forward<_Valty>(_Val));
		return (*this);
		}

	_Myt& operator*()
		{	// pretend to return designated value
		return (*this);
		}

	_Myt& operator++()
		{	// pretend to preincrement
		return (*this);
		}

	_Myt operator++(int)
		{	// pretend to postincrement
		return (*this);
		}

protected:
	_Container *container;	// pointer to container
	};

template<class _Container>
	struct _Is_checked_helper<front_insert_iterator<_Container> >
		: public true_type
	{	// mark front_insert_iterator as checked
	};

		// TEMPLATE FUNCTION front_inserter
template<class _Container> inline
	front_insert_iterator<_Container> front_inserter(_Container& _Cont)
	{	// return front_insert_iterator
	return (front_insert_iterator<_Container>(_Cont));
	}

		// TEMPLATE CLASS insert_iterator
template<class _Container>
	class insert_iterator
		: public _Outit
	{	// wrap inserts into container as output iterator
public:
	typedef insert_iterator<_Container> _Myt;
	typedef _Container container_type;
	typedef typename _Container::value_type _Valty;

	insert_iterator(_Container& _Cont, typename _Container::iterator _Where)
		: container(_STD addressof(_Cont)), iter(_Where)
		{	// construct with container and iterator
		}

	_Myt& operator=(const _Valty& _Val)
		{	// insert into container and increment stored iterator
		iter = container->insert(iter, _Val);
		++iter;
		return (*this);
		}

	_Myt& operator=(_Valty&& _Val)
		{	// push value into container
		iter = container->insert(iter, _STD forward<_Valty>(_Val));
		++iter;
		return (*this);
		}

	_Myt& operator*()
		{	// pretend to return designated value
		return (*this);
		}

	_Myt& operator++()
		{	// pretend to preincrement
		return (*this);
		}

	_Myt& operator++(int)
		{	// pretend to postincrement
		return (*this);
		}

protected:
	_Container *container;	// pointer to container
	typename _Container::iterator iter;	// iterator into container
	};

template<class _Container>
	struct _Is_checked_helper<insert_iterator<_Container> >
		: public true_type
	{	// mark insert_iterator as checked
	};

		// TEMPLATE FUNCTION inserter
template<class _Container> inline
	insert_iterator<_Container> inserter(_Container& _Cont,
		typename _Container::iterator _Where)
	{	// return insert_iterator
	return (insert_iterator<_Container>(_Cont, _Where));
	}

		// TEMPLATE CLASS istream_iterator

template<class _Ty,
	class _Elem = char,
	class _Traits = char_traits<_Elem>,
	class _Diff = ptrdiff_t>
	class istream_iterator
		: public iterator<input_iterator_tag, _Ty, _Diff,
			const _Ty *, const _Ty&>
	{	// wrap _Ty extracts from input stream as input iterator
	typedef istream_iterator<_Ty, _Elem, _Traits, _Diff> _Myt;
public:
	typedef _Elem char_type;
	typedef _Traits traits_type;
	typedef basic_istream<_Elem, _Traits> istream_type;

	typedef const _Ty *pointer;

	_CONST_FUN istream_iterator()
		: _Myistr(0), _Myval()
		{	// construct singular iterator
		}

	istream_iterator(istream_type& _Istr)
		: _Myistr(&_Istr)
		{	// construct with input stream
		_Getval();
		}

	const _Ty& operator*() const
		{	// return designated value
		return (_Myval);
		}

	pointer operator->() const
		{	// return pointer to class object
		return (_STD pointer_traits<pointer>::pointer_to(**this));
		}

	_Myt& operator++()
		{	// preincrement
		_Getval();
		return (*this);
		}

	_Myt operator++(int)
		{	// postincrement
		_Myt _Tmp = *this;
		++*this;
		return (_Tmp);
		}

	bool _Equal(const _Myt& _Right) const
		{	// test for iterator equality
		return (_Myistr == _Right._Myistr);
		}

protected:
	void _Getval()
		{	// get a _Ty value if possible
		if (_Myistr != 0 && !(*_Myistr >> _Myval))
			_Myistr = 0;
		}

	istream_type *_Myistr;	// pointer to input stream
	_Ty _Myval;	// lookahead value (valid if _Myistr is not null)
	};

template<class _Ty,
	class _Elem,
	class _Traits,
	class _Diff>
	struct _Is_checked_helper<istream_iterator<_Ty, _Elem, _Traits, _Diff> >
		: public true_type
	{	// mark istream_iterator as checked
	};

		// istream_iterator TEMPLATE OPERATORS
template<class _Ty,
	class _Elem,
	class _Traits,
	class _Diff> inline
	bool operator==(
		const istream_iterator<_Ty, _Elem, _Traits, _Diff>& _Left,
		const istream_iterator<_Ty, _Elem, _Traits, _Diff>& _Right)
	{	// test for istream_iterator equality
	return (_Left._Equal(_Right));
	}

template<class _Ty,
	class _Elem,
	class _Traits,
	class _Diff> inline
	bool operator!=(
		const istream_iterator<_Ty, _Elem, _Traits, _Diff>& _Left,
		const istream_iterator<_Ty, _Elem, _Traits, _Diff>& _Right)
	{	// test for istream_iterator inequality
	return (!(_Left == _Right));
	}

		// TEMPLATE CLASS ostream_iterator

template<class _Ty,
	class _Elem = char,
	class _Traits = char_traits<_Elem> >
	class ostream_iterator
		: public _Outit
	{	// wrap _Ty inserts to output stream as output iterator
public:
	typedef _Elem char_type;
	typedef _Traits traits_type;
	typedef basic_ostream<_Elem, _Traits> ostream_type;

	ostream_iterator(ostream_type& _Ostr,
		const _Elem *_Delim = 0)
		: _Myostr(&_Ostr), _Mydelim(_Delim)
		{	// construct from output stream and delimiter
		}

	ostream_iterator<_Ty, _Elem, _Traits>& operator=(const _Ty& _Val)
		{	// insert value into output stream, followed by delimiter
		*_Myostr << _Val;
		if (_Mydelim != 0)
			*_Myostr << _Mydelim;
		return (*this);
		}

	ostream_iterator<_Ty, _Elem, _Traits>& operator*()
		{	// pretend to return designated value
		return (*this);
		}

	ostream_iterator<_Ty, _Elem, _Traits>& operator++()
		{	// pretend to preincrement
		return (*this);
		}

	ostream_iterator<_Ty, _Elem, _Traits>& operator++(int)
		{	// pretend to postincrement
		return (*this);
		}

protected:
	const _Elem *_Mydelim;	// pointer to delimiter string (NB: not freed)
	ostream_type *_Myostr;	// pointer to output stream
	};

template<class _Ty,
	class _Elem,
	class _Traits>
	struct _Is_checked_helper<ostream_iterator<_Ty, _Elem, _Traits> >
		: public true_type
	{	// mark ostream_iterator as checked
	};
_STD_END

_STDEXT_BEGIN
using _STD iterator_traits;
using _STD size_t;

		// TEMPLATE CLASS checked_array_iterator
template<class _Iterator>
	class checked_array_iterator
	{	// wrap an iterator (actually, a pointer) with checking
public:
	typedef checked_array_iterator<_Iterator> _Myt;

	typedef typename iterator_traits<_Iterator>::iterator_category
		iterator_category;
	typedef typename iterator_traits<_Iterator>::value_type
		value_type;
	typedef typename iterator_traits<_Iterator>::difference_type
		difference_type;
	typedef typename iterator_traits<_Iterator>::pointer
		pointer;
	typedef typename iterator_traits<_Iterator>::reference
		reference;

	checked_array_iterator()
		: _Myarray(), _Mysize(0), _Myindex(0)
		{	// default construct
		}

	checked_array_iterator(_Iterator _Array, size_t _Size,
		size_t _Index = 0)
		: _Myarray(_Array), _Mysize(_Size), _Myindex(_Index)
		{	// construct with array, size, and optional index
		_SCL_SECURE_ALWAYS_VALIDATE(_Index <= _Size);
		}

	_Iterator base() const
		{	// return unwrapped iterator
		return (_Myarray + _Myindex);
		}

	typedef _Iterator _Unchecked_type;

	_Myt& _Rechecked(_Unchecked_type _Right)
		{	// reset from unchecked iterator
		_Myindex = _Right - _Myarray;
		return (*this);
		}

	_Unchecked_type _Unchecked() const
		{	// make an unchecked iterator
		return (base());
		}

	reference operator*() const
		{	// return designated object
		_SCL_SECURE_ALWAYS_VALIDATE_RANGE(_Myarray != 0
			&& _Myindex < _Mysize);
		return (_Myarray[_Myindex]);
		}

	pointer operator->() const
		{	// return pointer to class object
		return (_STD pointer_traits<pointer>::pointer_to(**this));
		}

	_Myt& operator++()
		{	// preincrement
		_SCL_SECURE_ALWAYS_VALIDATE_RANGE(_Myarray != 0
			&& _Myindex < _Mysize);
		++_Myindex;
		return (*this);
		}

	_Myt operator++(int)
		{	// postincrement
		_Myt _Tmp = *this;
		++*this;
		return (_Tmp);
		}

	_Myt& operator--()
		{	// predecrement
		_SCL_SECURE_ALWAYS_VALIDATE_RANGE(_Myarray != 0
			&& 0 < _Myindex);
		--_Myindex;
		return (*this);
		}

	_Myt operator--(int)
		{	// postdecrement
		_Myt _Tmp = *this;
		--*this;
		return (_Tmp);
		}

	_Myt& operator+=(difference_type _Off)
		{	// increment by integer
		_SCL_SECURE_ALWAYS_VALIDATE_RANGE(_Myarray != 0
			&& _Myindex + _Off <= _Mysize);
		_Myindex += _Off;
		return (*this);
		}

	_Myt operator+(difference_type _Off) const
		{	// return this + integer
		_Myt _Tmp = *this;
		return (_Tmp += _Off);
		}

	_Myt& operator-=(difference_type _Off)
		{	// decrement by integer
		return (*this += -_Off);
		}

	_Myt operator-(difference_type _Off) const
		{	// return this - integer
		_Myt _Tmp = *this;
		return (_Tmp -= _Off);
		}

	difference_type operator-(const _Myt& _Right) const
		{	// return difference of iterators
		_SCL_SECURE_ALWAYS_VALIDATE(_Myarray == _Right._Myarray);
		return (_Myindex - _Right._Myindex);
		}

	reference operator[](difference_type _Off) const
		{	// subscript
		return (*(*this + _Off));
		}

	bool operator==(const _Myt& _Right) const
		{	// test for iterator equality
		_SCL_SECURE_ALWAYS_VALIDATE(_Myarray == _Right._Myarray);
		return (_Myindex == _Right._Myindex);
		}

	bool operator!=(const _Myt& _Right) const
		{	// test for iterator inequality
		return (!(*this == _Right));
		}

	bool operator<(const _Myt& _Right) const
		{	// test if this < _Right
		_SCL_SECURE_ALWAYS_VALIDATE(_Myarray == _Right._Myarray);
		return (_Myindex < _Right._Myindex);
		}

	bool operator>(const _Myt& _Right) const
		{	// test if this > _Right
		return (_Right < *this);
		}

	bool operator<=(const _Myt& _Right) const
		{	// test if this <= _Right
		return (!(_Right < *this));
		}

	bool operator>=(const _Myt& _Right) const
		{	// test if this >= _Right
		return (!(*this < _Right));
		}

private:
	_Iterator _Myarray;	// beginning of array
	size_t _Mysize;	// size of array
	size_t _Myindex;	// offset into array
	};

template<class _Iterator> inline
	typename checked_array_iterator<_Iterator>::_Unchecked_type
		_Unchecked(checked_array_iterator<_Iterator> _Iter)
	{	// convert to unchecked
	return (_Iter._Unchecked());
	}

template<class _Iterator> inline
	checked_array_iterator<_Iterator>&
		_Rechecked(checked_array_iterator<_Iterator>& _Iter,
			typename checked_array_iterator<_Iterator>
				::_Unchecked_type _Right)
	{	// convert to checked
	return (_Iter._Rechecked(_Right));
	}

template<class _Iterator> inline
	checked_array_iterator<_Iterator> operator+(
		typename checked_array_iterator<_Iterator>::difference_type _Off,
		checked_array_iterator<_Iterator> _Next)
	{	// add offset to iterator
	return (_Next += _Off);
	}

template<class _Iterator> inline
	checked_array_iterator<_Iterator> make_checked_array_iterator(
		_Iterator _Array, size_t _Size, size_t _Index = 0)
	{	// construct with array, size, and optional index
	return (checked_array_iterator<_Iterator>(_Array, _Size, _Index));
	}

		// TEMPLATE CLASS unchecked_array_iterator
template<class _Iterator>
	class unchecked_array_iterator
	{	// wrap an iterator (pointer) without checking, to silence warnings
public:
	typedef unchecked_array_iterator<_Iterator> _Myt;

	typedef typename iterator_traits<_Iterator>::iterator_category
		iterator_category;
	typedef typename iterator_traits<_Iterator>::value_type
		value_type;
	typedef typename iterator_traits<_Iterator>::difference_type
		difference_type;
	typedef typename iterator_traits<_Iterator>::pointer
		pointer;
	typedef typename iterator_traits<_Iterator>::reference
		reference;

	unchecked_array_iterator()
		: _Myptr()
		{	// default construct
		}

	explicit unchecked_array_iterator(_Iterator _Ptr)
		: _Myptr(_Ptr)
		{	// construct with pointer
		}

	_Iterator base() const
		{	// return unwrapped iterator
		return (_Myptr);
		}

	typedef _Iterator _Unchecked_type;

	_Myt& _Rechecked(_Unchecked_type _Right)
		{	// reset from unchecked iterator
		_Myptr = _Right;
		return (*this);
		}

	_Unchecked_type _Unchecked() const
		{	// make an unchecked iterator
		return (base());
		}

	reference operator*() const
		{	// return designated object
		return (*_Myptr);
		}

	pointer operator->() const
		{	// return pointer to class object
		return (_STD pointer_traits<pointer>::pointer_to(**this));
		}

	_Myt& operator++()
		{	// preincrement
		++_Myptr;
		return (*this);
		}

	_Myt operator++(int)
		{	// postincrement
		_Myt _Tmp = *this;
		++*this;
		return (_Tmp);
		}

	_Myt& operator--()
		{	// predecrement
		--_Myptr;
		return (*this);
		}

	_Myt operator--(int)
		{	// postdecrement
		_Myt _Tmp = *this;
		--*this;
		return (_Tmp);
		}

	_Myt& operator+=(difference_type _Off)
		{	// increment by integer
		_Myptr += _Off;
		return (*this);
		}

	_Myt operator+(difference_type _Off) const
		{	// return this + integer
		_Myt _Tmp = *this;
		return (_Tmp += _Off);
		}

	_Myt& operator-=(difference_type _Off)
		{	// decrement by integer
		return (*this += -_Off);
		}

	_Myt operator-(difference_type _Off) const
		{	// return this - integer
		_Myt _Tmp = *this;
		return (_Tmp -= _Off);
		}

	difference_type operator-(const _Myt& _Right) const
		{	// return difference of iterators
		return (_Myptr - _Right._Myptr);
		}

	reference operator[](difference_type _Off) const
		{	// subscript
		return (*(*this + _Off));
		}

	bool operator==(const _Myt& _Right) const
		{	// test for iterator equality
		return (_Myptr == _Right._Myptr);
		}

	bool operator!=(const _Myt& _Right) const
		{	// test for iterator inequality
		return (!(*this == _Right));
		}

	bool operator<(const _Myt& _Right) const
		{	// test if this < _Right
		return (_Myptr < _Right._Myptr);
		}

	bool operator>(const _Myt& _Right) const
		{	// test if this > _Right
		return (_Right < *this);
		}

	bool operator<=(const _Myt& _Right) const
		{	// test if this <= _Right
		return (!(_Right < *this));
		}

	bool operator>=(const _Myt& _Right) const
		{	// test if this >= _Right
		return (!(*this < _Right));
		}

private:
	_Iterator _Myptr;	// underlying pointer
	};

template<class _Iterator> inline
	typename unchecked_array_iterator<_Iterator>::_Unchecked_type
		_Unchecked(unchecked_array_iterator<_Iterator> _Iter)
	{	// convert to unchecked
	return (_Iter._Unchecked());
	}

template<class _Iterator> inline
	unchecked_array_iterator<_Iterator>&
		_Rechecked(unchecked_array_iterator<_Iterator>& _Iter,
			typename unchecked_array_iterator<_Iterator>
				::_Unchecked_type _Right)
	{	// convert to checked
	return (_Iter._Rechecked(_Right));
	}

template<class _Iterator> inline
	unchecked_array_iterator<_Iterator> operator+(
		typename unchecked_array_iterator<_Iterator>::difference_type _Off,
		unchecked_array_iterator<_Iterator> _Next)
	{	// add offset to iterator
	return (_Next += _Off);
	}

template<class _Iterator> inline
	unchecked_array_iterator<_Iterator> make_unchecked_array_iterator(
		_Iterator _Ptr)
	{	// construct with pointer
	return (unchecked_array_iterator<_Iterator>(_Ptr));
	}
_STDEXT_END

 #pragma pop_macro("new")
 #pragma warning(pop)
 #pragma pack(pop)
#endif /* RC_INVOKED */
#endif /* _ITERATOR_ */

/*
 * Copyright (c) by P.J. Plauger. All rights reserved.
 * Consult your license regarding permissions and restrictions.
V6.50:0009 */