libstdc++
std::reverse_iterator< _Iterator > Class Template Reference
Inheritance diagram for std::reverse_iterator< _Iterator >:
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Public Types

typedef __traits_type::difference_type difference_type
 
typedef iterator_traits< _Iterator >::iterator_category iterator_category
 
typedef _Iterator iterator_type
 
typedef __traits_type::pointer pointer
 
typedef __traits_type::reference reference
 
typedef iterator_traits< _Iterator >::value_type value_type
 

Public Member Functions

constexpr reverse_iterator ()
 
constexpr reverse_iterator (const reverse_iterator &__x)
 
template<typename _Iter >
constexpr reverse_iterator (const reverse_iterator< _Iter > &__x)
 
constexpr reverse_iterator (iterator_type __x)
 
constexpr iterator_type base () const
 
constexpr reference operator* () const
 
constexpr reverse_iterator operator+ (difference_type __n) const
 
constexpr reverse_iteratoroperator++ ()
 
constexpr reverse_iterator operator++ (int)
 
constexpr reverse_iteratoroperator+= (difference_type __n)
 
constexpr reverse_iterator operator- (difference_type __n) const
 
constexpr reverse_iteratoroperator-- ()
 
constexpr reverse_iterator operator-- (int)
 
constexpr reverse_iteratoroperator-= (difference_type __n)
 
constexpr pointer operator-> () const
 
reverse_iteratoroperator= (const reverse_iterator &)=default
 
template<typename _Iter >
constexpr reverse_iteratoroperator= (const reverse_iterator< _Iter > &__x)
 
constexpr reference operator[] (difference_type __n) const
 

Protected Types

typedef iterator_traits< _Iterator > __traits_type
 

Protected Attributes

_Iterator current
 

Detailed Description

template<typename _Iterator>
class std::reverse_iterator< _Iterator >

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 i is established by the identity:

&*(reverse_iterator(i)) == &*(i - 1)

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.

Definition at line 127 of file bits/stl_iterator.h.

Member Typedef Documentation

◆ iterator_category

typedef iterator_traits< _Iterator >::iterator_category std::iterator< iterator_traits< _Iterator >::iterator_category , iterator_traits< _Iterator >::value_type , iterator_traits< _Iterator >::difference_type , iterator_traits< _Iterator >::pointer , iterator_traits< _Iterator >::reference >::iterator_category
inherited

One of the tag types.

Definition at line 130 of file stl_iterator_base_types.h.

◆ value_type

typedef iterator_traits< _Iterator >::value_type std::iterator< iterator_traits< _Iterator >::iterator_category , iterator_traits< _Iterator >::value_type , iterator_traits< _Iterator >::difference_type , iterator_traits< _Iterator >::pointer , iterator_traits< _Iterator >::reference >::value_type
inherited

The type "pointed to" by the iterator.

Definition at line 132 of file stl_iterator_base_types.h.

Constructor & Destructor Documentation

◆ reverse_iterator() [1/4]

template<typename _Iterator >
constexpr std::reverse_iterator< _Iterator >::reverse_iterator ( )
inlineconstexpr

The default constructor value-initializes member current. If it is a pointer, that means it is zero-initialized.

Definition at line 177 of file bits/stl_iterator.h.

◆ reverse_iterator() [2/4]

template<typename _Iterator >
constexpr std::reverse_iterator< _Iterator >::reverse_iterator ( iterator_type  __x)
inlineexplicitconstexpr

This iterator will move in the opposite direction that x does.

Definition at line 183 of file bits/stl_iterator.h.

◆ reverse_iterator() [3/4]

template<typename _Iterator >
constexpr std::reverse_iterator< _Iterator >::reverse_iterator ( const reverse_iterator< _Iterator > &  __x)
inlineconstexpr

The copy constructor is normal.

Definition at line 189 of file bits/stl_iterator.h.

◆ reverse_iterator() [4/4]

template<typename _Iterator >
template<typename _Iter >
constexpr std::reverse_iterator< _Iterator >::reverse_iterator ( const reverse_iterator< _Iter > &  __x)
inlineconstexpr

A reverse_iterator across other types can be copied if the underlying iterator can be converted to the type of current.

Definition at line 205 of file bits/stl_iterator.h.

Member Function Documentation

◆ base()

template<typename _Iterator >
constexpr iterator_type std::reverse_iterator< _Iterator >::base ( ) const
inlineconstexpr
Returns
current, the iterator used for underlying work.

Definition at line 227 of file bits/stl_iterator.h.

◆ operator*()

template<typename _Iterator >
constexpr reference std::reverse_iterator< _Iterator >::operator* ( ) const
inlineconstexpr
Returns
A reference to the value at –current

This requires that –current is dereferenceable.

Warning
This implementation requires that for an iterator of the underlying iterator type, x, a reference obtained by *x remains valid after x has been modified or destroyed. This is a bug: http://gcc.gnu.org/PR51823

Definition at line 241 of file bits/stl_iterator.h.

◆ operator+()

template<typename _Iterator >
constexpr reverse_iterator std::reverse_iterator< _Iterator >::operator+ ( difference_type  __n) const
inlineconstexpr
Returns
A reverse_iterator that refers to current - __n

The underlying iterator must be a Random Access Iterator.

Definition at line 322 of file bits/stl_iterator.h.

◆ operator++() [1/2]

template<typename _Iterator >
constexpr reverse_iterator& std::reverse_iterator< _Iterator >::operator++ ( )
inlineconstexpr
Returns
*this

Decrements the underlying iterator.

Definition at line 272 of file bits/stl_iterator.h.

◆ operator++() [2/2]

template<typename _Iterator >
constexpr reverse_iterator std::reverse_iterator< _Iterator >::operator++ ( int  )
inlineconstexpr
Returns
The original value of *this

Decrements the underlying iterator.

Definition at line 284 of file bits/stl_iterator.h.

◆ operator+=()

template<typename _Iterator >
constexpr reverse_iterator& std::reverse_iterator< _Iterator >::operator+= ( difference_type  __n)
inlineconstexpr
Returns
*this

Moves the underlying iterator backwards __n steps. The underlying iterator must be a Random Access Iterator.

Definition at line 332 of file bits/stl_iterator.h.

◆ operator-()

template<typename _Iterator >
constexpr reverse_iterator std::reverse_iterator< _Iterator >::operator- ( difference_type  __n) const
inlineconstexpr
Returns
A reverse_iterator that refers to current - __n

The underlying iterator must be a Random Access Iterator.

Definition at line 344 of file bits/stl_iterator.h.

◆ operator--() [1/2]

template<typename _Iterator >
constexpr reverse_iterator& std::reverse_iterator< _Iterator >::operator-- ( )
inlineconstexpr
Returns
*this

Increments the underlying iterator.

Definition at line 297 of file bits/stl_iterator.h.

◆ operator--() [2/2]

template<typename _Iterator >
constexpr reverse_iterator std::reverse_iterator< _Iterator >::operator-- ( int  )
inlineconstexpr
Returns
A reverse_iterator with the previous value of *this

Increments the underlying iterator.

Definition at line 309 of file bits/stl_iterator.h.

◆ operator-=()

template<typename _Iterator >
constexpr reverse_iterator& std::reverse_iterator< _Iterator >::operator-= ( difference_type  __n)
inlineconstexpr
Returns
*this

Moves the underlying iterator forwards __n steps. The underlying iterator must be a Random Access Iterator.

Definition at line 354 of file bits/stl_iterator.h.

◆ operator->()

template<typename _Iterator >
constexpr pointer std::reverse_iterator< _Iterator >::operator-> ( ) const
inlineconstexpr
Returns
A pointer to the value at –current

This requires that –current is dereferenceable.

Definition at line 253 of file bits/stl_iterator.h.

◆ operator[]()

template<typename _Iterator >
constexpr reference std::reverse_iterator< _Iterator >::operator[] ( difference_type  __n) const
inlineconstexpr
Returns
The value at current - __n - 1

The underlying iterator must be a Random Access Iterator.

Definition at line 366 of file bits/stl_iterator.h.


The documentation for this class was generated from the following file: