dasmig::core::json_writer Class Reference

Builds one JSON document. More...

#include <json.hpp>

Public Member Functions
	json_writer ()
	An empty writer, with room for a typical document.
json_writer &	begin_object ()
	Open an object.
json_writer &	end_object ()
	Close the innermost object.
json_writer &	begin_array ()
	Open an array.
json_writer &	end_array ()
	Close the innermost array.
json_writer &	key (std::string_view name)
	Write an object key; the next call writes its value.
json_writer &	value (std::string_view text)
	Write a string value.
json_writer &	value (const char *text)
	Write a string value (keeps string literals from binding to bool).
json_writer &	value (bool b)
	Write a boolean.
json_writer &	value (std::nullptr_t)
	Write null.
template<std::integral T> requires (!std::same_as<T, bool> && !std::same_as<T, char> && !std::same_as<T, wchar_t> && !std::same_as<T, char8_t> && !std::same_as<T, char16_t> && !std::same_as<T, char32_t>)
json_writer &	value (T n)
	Write an integer.
json_writer &	value (double d)
	Write a number, in the shortest form that reads back exactly.
template<typename V >
json_writer &	field (std::string_view name, const V &v)
	Write a key and its value.
bool	complete () const noexcept
	Whether exactly one complete value has been written.
const std::string &	str () const
	The document.

Static Public Member Functions
static void	escape (std::string &out, std::string_view text)
	Append a JSON string literal for text to out.

Detailed Description

Builds one JSON document.

dasmig::core::json_writer w;
w.begin_object()
    .field("name", "Ana")
    .field("age", 34)
    .key("tags").begin_array().value("calm").value("curious").end_array()
 .end_object();
std::string text = w.str();   // {"name":"Ana","age":34,"tags":["calm","curious"]}

Definition at line 48 of file json.hpp.

Constructor & Destructor Documentation

json_writer()

dasmig::core::json_writer::json_writer ( )

inline

An empty writer, with room for a typical document.

Definition at line 52 of file json.hpp.

Member Function Documentation

begin_array()

json_writer & dasmig::core::json_writer::begin_array ( )

inline

Open an array.

Returns

*this.

Exceptions

std::logic_error

Where a value is not allowed.

Definition at line 88 of file json.hpp.

begin_object()

json_writer & dasmig::core::json_writer::begin_object ( )

inline

Open an object.

Returns

*this.

Exceptions

std::logic_error

Where a value is not allowed.

Definition at line 61 of file json.hpp.

complete()

bool dasmig::core::json_writer::complete ( ) const

inlinenoexcept

Whether exactly one complete value has been written.

Returns

True when str() can be called.

Definition at line 217 of file json.hpp.

end_array()

json_writer & dasmig::core::json_writer::end_array ( )

inline

Close the innermost array.

Returns

*this.

Exceptions

std::logic_error

If the innermost container is not an array.

Definition at line 99 of file json.hpp.

end_object()

json_writer & dasmig::core::json_writer::end_object ( )

inline

Close the innermost object.

Returns

*this.

Exceptions

std::logic_error

If the innermost container is not an object, or a key has no value.

Definition at line 73 of file json.hpp.

escape()

static void dasmig::core::json_writer::escape ( std::string &  out, std::string_view  text  )

inlinestatic

Append a JSON string literal for text to out.

Parameters

out	Destination.
text	UTF-8 text.

Exceptions

std::invalid_argument

If text is not valid UTF-8.

Definition at line 235 of file json.hpp.

field()

template<typename V >

json_writer & dasmig::core::json_writer::field ( std::string_view  name, const V &  v  )

inline

Write a key and its value.

Parameters

name	UTF-8 key.
v	The value (any type value() accepts).

Returns

*this.

Definition at line 209 of file json.hpp.

key()

json_writer & dasmig::core::json_writer::key ( std::string_view  name )

inline

Write an object key; the next call writes its value.

Parameters

name	UTF-8 key.

Returns

*this.

Exceptions

std::logic_error	Outside an object or after another key.
std::invalid_argument	If name is not valid UTF-8.

Definition at line 116 of file json.hpp.

str()

const std::string & dasmig::core::json_writer::str ( ) const

inline

The document.

Returns

The JSON text.

Exceptions

std::logic_error

If the document is incomplete.

Definition at line 222 of file json.hpp.

value() [1/6]

json_writer & dasmig::core::json_writer::value ( bool  b )

inline

Write a boolean.

Parameters

b	The value.

Returns

*this.

Definition at line 149 of file json.hpp.

value() [2/6]

json_writer & dasmig::core::json_writer::value ( const char *  text )

inline

Write a string value (keeps string literals from binding to bool).

Parameters

text	Null-terminated UTF-8 text.

Returns

*this.

Definition at line 144 of file json.hpp.

value() [3/6]

json_writer & dasmig::core::json_writer::value ( double  d )

inline

Write a number, in the shortest form that reads back exactly.

Parameters

d	The value.

Returns

*this.

Exceptions

std::invalid_argument

If d is NaN or infinite (JSON has no representation for them).

Definition at line 190 of file json.hpp.

value() [4/6]

json_writer & dasmig::core::json_writer::value ( std::nullptr_t  )

inline

Write null.

Returns

*this.

Definition at line 159 of file json.hpp.

value() [5/6]

json_writer & dasmig::core::json_writer::value ( std::string_view  text )

inline

Write a string value.

Parameters

text	UTF-8 text.

Returns

*this.

Exceptions

std::invalid_argument

If text is not valid UTF-8.

Definition at line 133 of file json.hpp.

value() [6/6]

template<std::integral T>
requires (!std::same_as<T, bool> && !std::same_as<T, char> && !std::same_as<T, wchar_t> && !std::same_as<T, char8_t> && !std::same_as<T, char16_t> && !std::same_as<T, char32_t>)

json_writer & dasmig::core::json_writer::value ( T  n )

inline

Write an integer.

Template Parameters

T	Integral type other than bool and the character types.

Parameters

n	The value.

Returns

*this.

Definition at line 175 of file json.hpp.

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

• dasmig/core/json.hpp