bsoncxx::document::view Class Reference

#include <bsoncxx/v_noabi/bsoncxx/document/view.hpp>

Description

A read-only, non-owning view of a BSON document.

Classes
class	const_iterator
	A const iterator over the contents of a document view. More...

Public Types
using	iterator = const_iterator
	Equivalent to const_iterator.

Public Member Functions
	view ()
	Default constructs a view.
	view (std::uint8_t const *data, std::size_t length)
	Constructs a view from a buffer. The caller is responsible for ensuring that the lifetime of the resulting view is a subset of the buffer's.
	view (v1::document::view const &v)
	Construct with the bsoncxx::v1 equivalent.
const_iterator	begin () const
const_iterator	cbegin () const
const_iterator	cend () const
std::uint8_t const *	data () const
	Access the raw bytes of the underlying document.
bool	empty () const
	Return true when this->length() == 5.
const_iterator	end () const
const_iterator	find (v1::stdx::string_view key) const
	Finds the first element of the document with the provided key. If there is no such element, the past-the-end iterator will be returned. The runtime of find() is linear in the length of the document. This method only searches the top-level document, and will not recurse to any subdocuments.
std::size_t	length () const
	Gets the length of the underlying buffer in bytes.
	operator v1::document::view () const
	Convert to the bsoncxx::v1 equivalent.
v_noabi::document::element	operator[] (v1::stdx::string_view key) const
	Finds the first element of the document with the provided key. If there is no such element, the invalid document::element will be returned. The runtime of operator[] is linear in the length of the document.
std::size_t	size () const
	Gets the length of the underlying buffer in bytes.

Related Symbols
(Note that these are not member symbols.)
bool	operator== (view lhs, view rhs)
	Compare two document views for (in)-equality.
bool	operator!= (view lhs, view rhs)
	Compare two document views for (in)-equality.

Member Typedef Documentation

iterator

using bsoncxx::v_noabi::document::view::iterator = const_iterator

Equivalent to const_iterator.

Constructor & Destructor Documentation

view() [1/3]

bsoncxx::v_noabi::document::view::view ( )

inline

Default constructs a view.

Postconditions:

• this->data() != nullptr
• this->size() == 5
• this->empty() == true

view() [2/3]

bsoncxx::v_noabi::document::view::view ( v1::document::view const & v )

inline

Construct with the bsoncxx::v1 equivalent.

view() [3/3]

bsoncxx::v_noabi::document::view::view ( std::uint8_t const * data, std::size_t length )

inline

Constructs a view from a buffer. The caller is responsible for ensuring that the lifetime of the resulting view is a subset of the buffer's.

Warning

For backward compatibility, length is NOT validated. When length is inconsistent with the embedded length as indicated by the BSON bytes, the BSON bytes may be parsed as "invalid" despite the BSON bytes themselves being valid.

Parameters

data	A pointer to valid BSON data.
length	The size of the BSON data in bytes.

Member Function Documentation

begin()

view::const_iterator bsoncxx::v_noabi::document::view::begin ( ) const

inline

Returns

A const_iterator to the first element of the document.

cbegin()

const_iterator bsoncxx::v_noabi::document::view::cbegin

(

)

const

Returns

A const_iterator to the first element of the document.

cend()

view::const_iterator bsoncxx::v_noabi::document::view::cend ( ) const

inline

Returns

A const_iterator to the past-the-end element of the document.

data()

std::uint8_t const * bsoncxx::v_noabi::document::view::data ( ) const

inline

Access the raw bytes of the underlying document.

Returns

A (non-owning) pointer to the view's buffer.

empty()

bool bsoncxx::v_noabi::document::view::empty ( ) const

inline

Return true when this->length() == 5.

Warning

For backward compatibility, this function does NOT check if the underlying BSON bytes represent a valid empty document.

end()

view::const_iterator bsoncxx::v_noabi::document::view::end ( ) const

inline

Returns

A const_iterator to the past-the-end element of the document.

find()

const_iterator bsoncxx::v_noabi::document::view::find

(

v1::stdx::string_view

key

)

const

Finds the first element of the document with the provided key. If there is no such element, the past-the-end iterator will be returned. The runtime of find() is linear in the length of the document. This method only searches the top-level document, and will not recurse to any subdocuments.

Remarks

In BSON, keys are not required to be unique. If there are multiple elements with a matching key in the document, the first matching element from the start will be returned.

Parameters

key	The key to search for.

Returns

An iterator to the matching element, if found, or the past-the-end iterator.

length()

std::size_t bsoncxx::v_noabi::document::view::length ( ) const

inline

Gets the length of the underlying buffer in bytes.

Remarks

This is not the number of BSON elements. To compute the number of elements, use std::distance.

Returns

The length of the document, in bytes.

operator v1::document::view()

bsoncxx::v_noabi::document::view::operator v1::document::view ( ) const

inlineexplicit

Convert to the bsoncxx::v1 equivalent.

Preconditions:

• If this->data() is not null, the size of the storage region pointed to by data must be greater than or equal to 5.
• The "total number of bytes comprising the document" as indicated by the BSON bytes pointed-to by this->data() must be less than or equal to the size of the storage region pointed to by data.

Note

this->size() is ignored.

operator[]()

v_noabi::document::element bsoncxx::v_noabi::document::view::operator[] ( v1::stdx::string_view key ) const

inline

Finds the first element of the document with the provided key. If there is no such element, the invalid document::element will be returned. The runtime of operator[] is linear in the length of the document.

Parameters

key	The key to search for.

Returns

The matching element, if found, or the invalid element.

size()

std::size_t bsoncxx::v_noabi::document::view::size ( ) const

inline

Gets the length of the underlying buffer in bytes.

Remarks

This is not the number of BSON elements. To compute the number of elements, use std::distance.

Returns

The length of the document, in bytes.

Friends And Related Symbol Documentation

operator!=

bool operator!= ( view lhs, view rhs )

friend

Compare two document views for (in)-equality.

operator==

bool operator== ( view lhs, view rhs )

friend

Compare two document views for (in)-equality.

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

• bsoncxx/v_noabi/bsoncxx/document/view.hpp