Lightweight class to ease writting JSON documents, a subset of YAML (http://json.org) More...

#include <Emitter.hh>

Inheritance diagram for basic::JsonEmitter:

Public Member Functions
	JsonEmitter (std::ostream &out)

	~JsonEmitter () override

void	start_doc () override
	JSON doesn't support multiple documents, so this just calls end(1) to return you to the top (least-nested) level. More...

Public Member Functions inherited from basic::Emitter
	Emitter (std::ostream &out)

	~Emitter () override

void	flush ()
	Flush the underlying output stream. More...

template<typename T >
void	write (T const &data)
	Write method for use inside lists / arrays. More...

void	start_list (bool indent=true)
	Write method for use inside lists / arrays. More...

void	start_map (bool indent=true)
	Write method for use inside lists / arrays. More...

template<typename T >
void	write (std::string const &label, T const &data)
	Write method for use inside maps / dicts / objects. More...

void	start_list (std::string const &label, bool indent=true)
	Write method for use inside maps / dicts / objects. More...

void	start_list (const char *label, bool indent=true)
	Write method for use inside maps / dicts / objects. More...

void	start_map (std::string const &label, bool indent=true)
	Write method for use inside maps / dicts / objects. More...

void	start_map (const char *label, bool indent=true)
	Write method for use inside maps / dicts / objects. More...

void	end_list ()
	Counterpart to start_list() – writes closing bracket. More...

void	end_map ()
	Counterpart to start_map() – writes closing brace. More...

void	end (size_t desired_depth=0)
	By default, closes all open maps/lists, ending the document. More...

int	depth () const
	Number of closing brackets/braces required to end document (non-negative) More...

void	set_indent (int num_spaces)
	Number of spaces used for indenting. Default is one. More...

Public Member Functions inherited from utility::VirtualBase
	VirtualBase ()=default
	Default constructor. More...

virtual	~VirtualBase ()=default
	The virtual destructor is one of the main reasons for the VirtualBase class. More...

	VirtualBase (VirtualBase const &)=default

	VirtualBase (VirtualBase &&)=default

VirtualBase &	operator= (VirtualBase const &)=default

VirtualBase &	operator= (VirtualBase &&)=default

Protected Member Functions
std::string	quote_string (std::string const &s) override
	JSON always quotes strings, regardless. More...

void	do_indent (bool write_comma=true) override
	Handle pretty-printing indentation. Don't want to use commas for opening/closing brace/bracket. More...

void	write_list_marker () override
	JSON has no special marker for list items. More...

void	start_raw (bool is_map, bool indent) override

void	end_raw () override

Protected Member Functions inherited from basic::Emitter
	Emitter ()

	Emitter (Emitter const &)

bool	assert_in (bool in_map, std::string const &msg)
	Check that we're in the expected context (either map or list) More...

void	write_label (std::string const &label)
	Write the key part of a key-value pair. More...

void	write_raw (bool b)

void	write_raw (int i)

void	write_raw (long l)

void	write_raw (float f)

void	write_raw (double d)

void	write_raw (std::string const &s)

std::string	escape_string (std::string const &s, bool &needs_quotes_out)
	Converts special characters (newlines, etc) to escape codes ( , etc). More...

Private Member Functions
	JsonEmitter ()

	JsonEmitter (JsonEmitter const &)

Additional Inherited Members
Protected Attributes inherited from basic::Emitter
std::ostream &	out_

std::string	indent_str_

std::vector< bool >	in_map_

std::vector< bool >	first_

std::vector< bool >	indent_

std::vector< int >	indent_depth_

Detailed Description

Lightweight class to ease writting JSON documents, a subset of YAML (http://json.org)

Using this class is not recommended – use YamlEmitter instead.

JSON is JavaScript Object Notation, the format for object and array literals in the JavaScript language. It also looks a great deal like nested Python dicts and lists, except for the special JSON values true, false, and null. (Python uses True, False, and None instead. Otherwise, JSON can be embedded directly into Python scripts.)

JSON is legal subset of YAML, but leaves out much of YAML's complexity and advanced features. At the present time, there appears to be more library support for JSON than for YAML, especially for reading and parsing. (Both are fairly easy to write, as demonstrated here.)

The topmost level of every valid JSON document consists of exactly one map, which is automatically started for you when the class is initialized. When you're finished you should call end(), and then probably flush().

Whitespace is JSON documents is not significant. By default, this class will try to pretty-print, showing the depth of nesting through indentation. When starting a new list or map, you can request that it not be indented (i.e., be printed all on one line), but all lists and maps nested inside it will also be printed without linebreaks, regardless of the requested indentation.