mongocxx::v1::cursor::iterator Class Reference

#include <mongocxx/v1/cursor.hpp>

Description

An iterator over the results of an associated cursor.

Attention

This feature is experimental! It is not ready for use!

Important

All iterators associated with the same cursor object share the same state.

The end iterator has no associated cursor.

Note

This iterator almost satisfies Cpp17ForwardIterator, but std::iterator_traits<T>::reference is defined as value_type, similar to std::vector<bool>::iterator and std::istreambuf_iterator<T>. Therefore, this iterator only fully satisfies Cpp17InputIterator.

See also

• Cursors (MongoDB Manual)

Public Types
using	difference_type = std::ptrdiff_t
	Provide std::iterator_traits<T>::difference_type.
using	iterator_category = std::input_iterator_tag
	Provide std::iterator_traits<T>::iterator_category.
using	pointer = value_type const*
	Provide std::iterator_traits<T>::pointer.
using	reference = value_type
	Provide std::iterator_traits<T>::reference.
using	value_type = bsoncxx::v1::document::view
	Provide std::iterator_traits<T>::value_type.

Public Member Functions
	iterator ()
	Initialize as an end iterator.
	iterator (iterator &&other) noexcept
	Move construction.
	iterator (iterator const &other)
	Copy construction.
	~iterator ()
	Destroy this object.
value_type	operator* () const
	Access the current cursor result document.
iterator &	operator++ ()
	Increment this iterator.
iterator &	operator++ (int)
	Increment this iterator.
pointer	operator-> () const
	Access the current result document.
iterator &	operator= (iterator &&other) noexcept
	Move assignment.
iterator &	operator= (iterator const &other)
	Copy assignment.

Friends
bool	operator!= (iterator const &lhs, iterator const &rhs)
	Equivalent to !(lhs == rhs).
bool	operator== (iterator const &lhs, iterator const &rhs)
	Equality comparison.

Member Typedef Documentation

difference_type

using mongocxx::v1::cursor::iterator::difference_type = std::ptrdiff_t

Provide std::iterator_traits<T>::difference_type.

iterator_category

using mongocxx::v1::cursor::iterator::iterator_category = std::input_iterator_tag

Provide std::iterator_traits<T>::iterator_category.

pointer

using mongocxx::v1::cursor::iterator::pointer = value_type const*

Provide std::iterator_traits<T>::pointer.

reference

using mongocxx::v1::cursor::iterator::reference = value_type

Provide std::iterator_traits<T>::reference.

value_type

using mongocxx::v1::cursor::iterator::value_type = bsoncxx::v1::document::view

Provide std::iterator_traits<T>::value_type.

Constructor & Destructor Documentation

~iterator()

mongocxx::v1::cursor::iterator::~iterator

(

)

Destroy this object.

Warning

Invalidates all associated views.

iterator() [1/3]

mongocxx::v1::cursor::iterator::iterator ( iterator && other )

noexcept

Move construction.

Postconditions:

• other is in an assign-or-destroy-only state.

iterator() [2/3]

mongocxx::v1::cursor::iterator::iterator

(

iterator const &

other

)

Copy construction.

iterator() [3/3]

mongocxx::v1::cursor::iterator::iterator

(

)

Initialize as an end iterator.

Member Function Documentation

operator*()

value_type mongocxx::v1::cursor::iterator::operator*

(

)

const

Access the current cursor result document.

operator++() [1/2]

iterator & mongocxx::v1::cursor::iterator::operator++

(

)

Increment this iterator.

Advance the underlying cursor to obtain the next result document. Compare equal to the end iterator when there are no result documents available.

Note

Pre-increment and post-increment are equivalent.

Warning

Invalidates all views to the current result document.

Exceptions

mongocxx::v1::server_error	when a server-side error is encountered and a raw server error is available.
mongocxx::v1::exception	for all other runtime errors.

operator++() [2/2]

iterator & mongocxx::v1::cursor::iterator::operator++ ( int )

inline

Increment this iterator.

Advance the underlying cursor to obtain the next result document. Compare equal to the end iterator when there are no result documents available.

Note

Pre-increment and post-increment are equivalent.

Warning

Invalidates all views to the current result document.

Exceptions

mongocxx::v1::server_error	when a server-side error is encountered and a raw server error is available.
mongocxx::v1::exception	for all other runtime errors.

operator->()

pointer mongocxx::v1::cursor::iterator::operator->

(

)

const

Access the current result document.

Preconditions:

• *this does not compare equal to the end iterator.

Returns

Empty when there is no result document available.

operator=() [1/2]

iterator & mongocxx::v1::cursor::iterator::operator= ( iterator && other )

noexcept

Move assignment.

Postconditions:

• other is in an assign-or-destroy-only state.

operator=() [2/2]

iterator & mongocxx::v1::cursor::iterator::operator=

(

iterator const &

other

)

Copy assignment.

Friends And Related Symbol Documentation

operator!=

bool operator!= ( iterator const & lhs, iterator const & rhs )

friend

Equivalent to !(lhs == rhs).

operator==

bool operator== ( iterator const & lhs, iterator const & rhs )

friend

Equality comparison.

lhs and rhs compare equal when:

• both are associated with the same cursor object, or
• both are end iterators, or
• one is an end iterator and the other has no result document available.

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

• mongocxx/v1/cursor.hpp