mlib::json::node Class Reference

Representation of a JSON node. More...

#include <json.h>

Classes
class	iterator_type
	node iterator More...

Public Types
using	pnode = std::unique_ptr<node>
using	nodes_map = std::map<const std::string, pnode>
using	nodes_array = std::vector<pnode>
typedef iterator_type< false >	iterator
typedef iterator_type< true >	const_iterator

Public Member Functions
	node (type t=type::null)
	Constructor for an empty node.
	node (const std::string &s)
	Constructor for a string type node.
	node (const char *s)
	Alternate constructor for a string node.
	node (double d)
	Constructor for a numeric node.
	node (int d)
	Alternate constructor for a numeric node.
	node (bool b)
	Constructor for a boolean node.
template<typename T>
	node (const std::vector< T > &vec)
	Constructor from a vector.
template<class T>
	node (const T &t, decltype(&T::to_json) *=nullptr)
	Constructor from an object.
	node (const node &other)
	Copy constructor.
	node (node &&other)
	Move constructor.
node &	operator= (const node &rhs)
	Principal assignment operator.
node &	operator= (node &&rhs)
	Move assignment operator.
template<class T, typename B = decltype (&T::to_json)>
node &	operator= (const T &t)
	Assignment operator.
node &	operator= (bool b)
	Boolean assignment.
template<typename T, typename B = std::enable_if_t<std::is_arithmetic_v<T>>>
node &	operator= (T n)
	Numeric assignment.
node &	operator= (const std::string &s)
	String assignment.
node &	operator= (const char *s)
	C string assignment.
	operator std::string () const
	Return node value as a string (if possible)
	operator const char * () const
	operator double () const
	Return numeric value of a node.
	operator float () const
	Return numeric value of a node.
	operator int () const
	operator bool () const
	Return boolean value of the node.
double	to_num () const
std::string	to_str () const
	String conversion function.
bool	to_bool () const
	Conversion to boolean value.
node &	operator[] (const std::string &name)
	Return value of an object node element.
const node &	operator[] (const std::string &name) const
	Return value of an object node element (const version).
node &	at (const std::string &name)
	Return value of an object node element.
const node &	at (const std::string &name) const
	Return value of an object node element.
node &	operator[] (size_t index)
	Return value of an array node element.
const node &	operator[] (size_t index) const
	Return value of an array node element (const version).
node &	at (size_t index)
	Return value of an object node element.
const node &	at (size_t index) const
	Return value of an array node element (const version).
void	push_back (const node &n)
	Append an element at the end of an array.
const_iterator	begin () const
	Begin iterator (const variant)
iterator	begin ()
	Begin iterator (non-const variant)
const_iterator	end () const
	End iterator (const variant)
iterator	end ()
	End iterator (non-const variant)
bool	operator== (const node &other) const
	Equality operator.
bool	operator!= (const node &other) const
	inequality operator
mlib::erc	read (std::istream &s)
	Deserialize the node from an input stream.
mlib::erc	read (const std::string &s)
	Parse a string to a JSON node.
mlib::erc	write (std::string &s, int flags=0, int spaces=0) const
	Write node to a string.
bool	has (const std::string &name) const
	Return true if node is an object and has a child with that name.
const node *	find (const std::string &name) const
	If node is an object and has a child with the given name, returns a pointer to child node.
node *	find (const std::string &name)
	If node is an object and has a child with the given key name, returns a pointer to child node.
node *	search_key (const std::string &name)
	Search all descendant nodes for the given key name.
const node *	search_key (const std::string &name) const
	Search all descendant nodes for the given key name.
void	erase (const std::string &name)
	Erase the child with that name, if it exists.
void	clear (type t=type::null)
	Remove previous node content.
type	kind () const
	Return the type of node.
int	size () const
	Return number of direct descendants.
void	format (const std::string &f)
	Set output format for numerical values.
const std::string_view	format () const
	Return output format for numerical values.

Friends
std::ostream &	operator<< (std::ostream &os, const node &n)
	Insertion operator serializes a JSON node to an output stream.

Detailed Description

Representation of a JSON node.

Member Function Documentation

at() [1/4]

node & mlib::json::node::at ( const std::string & name )

inline

Return value of an object node element.

If element doesn't exist it throws an ERR_JSON_MISSING exception.

at() [2/4]

const node & mlib::json::node::at

(

const std::string &

name

)

const

Return value of an object node element.

If element doesn't exist throws an ERR_JSON_MISSING exception.

at() [3/4]

node & mlib::json::node::at ( size_t index )

inline

Return value of an object node element.

If element doesn't exist it throws an ERR_JSON_MISSING exception.

at() [4/4]

const node & mlib::json::node::at

(

size_t

index

)

const

Return value of an array node element (const version).

If element doesn't exist throws an ERR_JSON_MISSING exception.

find() [1/2]

node * mlib::json::node::find

(

const std::string &

name

)

If node is an object and has a child with the given key name, returns a pointer to child node.

Otherwise returns nullptr

find() [2/2]

const node * mlib::json::node::find

(

const std::string &

name

)

const

If node is an object and has a child with the given name, returns a pointer to child node.

Otherwise returns nullptr

operator[]() [1/4]

node & mlib::json::node::operator[]

(

const std::string &

name

)

Return value of an object node element.

If name doesn't exist, it is appended to node.

operator[]() [2/4]

const node & mlib::json::node::operator[]

(

const std::string &

name

)

const

Return value of an object node element (const version).

If element doesn't exist it throws an ERR_JSON_MISSING exception.

operator[]() [3/4]

node & mlib::json::node::operator[]

(

size_t

index

)

Return value of an array node element.

If element doesn't exist the array is extended with null elements.

operator[]() [4/4]

const node & mlib::json::node::operator[]

(

size_t

index

)

const

Return value of an array node element (const version).

If element doesn't exist throws an ERR_JSON_MISSING exception.

read()

erc mlib::json::node::read

(

const std::string &

s

)

Parse a string to a JSON node.

Returns an error if there are any extra characters after the JSON text.

search_key() [1/2]

node * mlib::json::node::search_key

(

const std::string &

name

)

Search all descendant nodes for the given key name.

Parameters

name

key name

Returns

pointer to descendant node or nullptr if not found

search_key() [2/2]

const node * mlib::json::node::search_key ( const std::string & name ) const

inline

Search all descendant nodes for the given key name.

Parameters

name

key name

Returns

pointer to descendant node or nullptr if not found

write()

mlib::erc mlib::json::node::write	(	std::string &	s,
		int	flags = 0,
		int	spaces = 0 ) const

Write node to a string.

Parameters

s	output string
flags	formatting flags
spaces	number of spaces to indent. If 0 uses tabs instead of spaces

Friends And Related Symbol Documentation

operator<<

std::ostream & operator<< ( std::ostream & os, const node & n )

friend

Insertion operator serializes a JSON node to an output stream.

Write a JSON object to a stream.

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

• include/mlib/json.h
• src/json.cpp