nlohmann::basic_json

a class to store JSON values

Synopsis

Declared in <nlohmann/json.hpp>

template<
    template<
    typename U,
    typename V,
    typename... Args> typename ObjectType = map,
    template<
    typename U,
    typename... Args> typename ArrayType = vector,
    class StringType = std::string,
    class BooleanType = bool,
    class NumberIntegerType = int64_t,
    class NumberUnsignedType = uint64_t,
    class NumberFloatType = double,
    template<typename U> typename AllocatorType = allocator,
    template<
    typename T,
    typename SFINAE = void> typename JSONSerializer = adl_serializer,
    class BinaryType = std::vector<uint8_t>,
    class CustomBaseClass = void>
class basic_json
    : public nlohmann::detail::json_base_class<CustomBaseClass>

Base Classes

Name	Description
`nlohmann::detail::json_base_class<CustomBaseClass>`

Types

Name	Description
`allocator_type`	the allocator type
`array_t`	a type for an array
`binary_t`	a type for a packed binary type
`bjdata_version_t`	how to encode BJData
`boolean_t`	a type for a boolean
`cbor_tag_handler_t`	how to treat CBOR tags
`const_iterator`	a const iterator for a basic_json container
`const_pointer`	the type of an element const pointer
`const_reference`	the type of an element const reference
`const_reverse_iterator`	a const reverse iterator for a basic_json container
`default_object_comparator_t`
`difference_type`	a type to represent differences between iterators
`error_handler_t`	how to treat decoding errors
`exception`	Classes to implement user-defined exceptions. @{
`initializer_list_t`	helper type for initializer lists of basic_json values
`input_format_t`
`invalid_iterator`
`iterator`	an iterator for a basic_json container
`json_pointer`	JSON Pointer, see `nlohmann::json_pointer`
`json_sax_t`	SAX interface type, see `nlohmann::json_sax`
`json_serializer`
`number_float_t`	a type for a number (floating-point)
`number_integer_t`	a type for a number (integer)
`number_unsigned_t`	a type for a number (unsigned)
`object_comparator_t`	object key comparator type
`object_t`	a type for an object
`other_error`
`out_of_range`
`parse_error`
`parse_event_t`	parser event types
`parser_callback_t`	per-element parser callback type
`pointer`	the type of an element pointer
`reference`	the type of an element reference
`reverse_iterator`	a reverse iterator for a basic_json container
`size_type`	a type to represent container sizes
`string_t`	a type for a string
`type_error`
`value_t`
`value_type`	the type of elements in a basic_json container

Member Functions

Name	Description
`basic_json` [constructor]	copy constructor
`basic_json` [constructor]	move constructor
`basic_json` [constructor]	create a null object
`basic_json` [constructor]	create an empty value with a given type
`basic_json` [constructor]	create a JSON value from an existing one
`basic_json` [constructor]	////////////////////////////////////
`basic_json` [constructor]	create a JSON value from compatible types
`basic_json` [constructor]	construct an array with count copies of given value
`basic_json` [constructor]	construct a JSON container given an iterator range
`basic_json` [constructor]	create a container (array or object) from an initializer list
`~basic_json` [destructor]	destructor
`operator=`	copy assignment
`at`	access specified array element with bounds checking
`at`	access specified array element with bounds checking
`at`	access specified element via JSON Pointer
`at`	access specified element via JSON Pointer
`at`	access specified object element with bounds checking
`at`	access specified object element with bounds checking
`at`
`at`
`at`	access specified object element with bounds checking
`at`	access specified object element with bounds checking
`back`	access the last element
`back`	access the last element
`begin`	returns an iterator to the first element
`begin`	returns an iterator to the first element
`cbegin`	returns a const iterator to the first element
`cend`	returns an iterator to one past the last element
`clear`	clears the contents
`contains`	check the existence of an element in a JSON object given a JSON pointer
`contains`	check the existence of an element in a JSON object
`contains`
`contains`	check the existence of an element in a JSON object
`count`	returns the number of occurrences of a key in a JSON object
`count`	returns the number of occurrences of a key in a JSON object
`crbegin`	returns a const reverse iterator to the last element
`crend`	returns a const reverse iterator to one before the first
`dump`	serialization
`emplace`	add an object to an object if key does not exist
`emplace_back`	add an object to an array
`empty`	checks whether the container is empty.
`end`	returns an iterator to one past the last element
`end`	returns an iterator to one past the last element
`erase`	remove element from a JSON array given an index
`erase`	remove element from a JSON object given a key
`erase`	remove element given an iterator
`erase`	remove element from a JSON object given a key
`erase`	remove elements given an iterator range
`find`	find an element in a JSON object
`find`	find an element in a JSON object
`find`	find an element in a JSON object
`find`	find an element in a JSON object
`flatten`	return flattened JSON value
`front`	access the first element
`front`	access the first element
`get`	get a pointer value (explicit)
`get`	get a (pointer) value (explicit)
`get_binary`	get a binary value
`get_binary`	get a binary value
`get_ptr`	get a pointer value (implicit)
`get_ptr`	get a pointer value (implicit)
`get_ref`	get a reference value (implicit)
`get_ref`	get a reference value (implicit)
`get_to`	get a value (explicit)
`get_to`
`get_to`
`insert`	inserts range of elements into object
`insert`	inserts elements from initializer list into array
`insert`	inserts element into array
`insert`	inserts element into array
`insert`	inserts range of elements into array
`insert`	inserts copies of element into array
`insert_iterator`	Helper for insertion of an iterator
`is_array`	return whether value is an array
`is_binary`	return whether value is a binary array
`is_boolean`	return whether value is a boolean
`is_discarded`	return whether value is discarded
`is_null`	return whether value is null
`is_number`	return whether value is a number
`is_number_float`	return whether value is a floating-point number
`is_number_integer`	return whether value is an integer number
`is_number_unsigned`	return whether value is an unsigned integer number
`is_object`	return whether value is an object
`is_primitive`	return whether type is primitive
`is_string`	return whether value is a string
`is_structured`	return whether type is structured
`items`	helper to access iterator member functions in range-based for
`items`	helper to access iterator member functions in range-based for
`max_size`	returns the maximum possible number of elements
`merge_patch`	applies a JSON Merge Patch
`operator+=`	add an object to an object
`operator+=`	add an object to an array
`operator+=`	add an object to an object
`operator+=`	add an object to an array
`operator[]`	access specified object element
`operator[]`	access specified array element
`operator[]`	access specified array element
`operator[]`	access specified element via JSON Pointer
`operator[]`	access specified element via JSON Pointer
`operator[]`	access specified object element
`operator[]`	Subscript operator
`operator[]`	Subscript operator
`operator[]`	access specified object element
`operator[]`	access specified object element
`operator[]`	Subscript operator
`operator[]`	Subscript operator
`patch`	applies a JSON patch to a copy of the current object
`patch_inplace`	applies a JSON patch in-place without copying the object
`push_back`	add an object to an object
`push_back`	add an object to an array
`push_back`	add an object to an object
`push_back`	add an object to an array
`rbegin`	returns an iterator to the reverse-beginning
`rbegin`	returns an iterator to the reverse-beginning
`rend`	returns an iterator to the reverse-end
`rend`	returns an iterator to the reverse-end
`size`	returns the number of elements
`swap`	exchanges the values
`swap`	exchanges the values
`swap`	exchanges the values
`swap`	exchanges the values
`swap`	exchanges the values
`swap`	exchanges the values
`type`	return the type of the JSON value (explicit)
`type_name`	return the type as string
`unflatten`	unflatten a previously flattened JSON value
`update`	updates a JSON object from another object, overwriting existing keys
`update`	updates a JSON object from another object, overwriting existing keys
`value`	access specified object element via JSON Pointer with default value
`value`	access specified object element with default value
`value`	access specified object element via JSON Pointer with default value
`value`	access specified object element with default value
`value`
`value`	access specified object element with default value
`value`
`value`	access specified object element via JSON Pointer with default value
`operator ValueType`	get a value (implicit)
`operator value_t`	return the type of the JSON value (implicit)
`operator==`	comparison: equal
`operator==`	comparison: equal
`operator!=`	comparison: not equal
`operator<=>`	comparison: 3-way
`operator<=>`	comparison: 3-way

Static Member Functions

Name	Description
`accept`
`accept`	check if the input is valid JSON
`accept`	check if the input is valid JSON
`array`	explicitly create an array from an initializer list
`binary`	explicitly create a binary array (without subtype)
`binary`	explicitly create a binary array
`binary`	explicitly create a binary array (with subtype)
`binary`	explicitly create a binary array (with subtype)
`diff`	creates a diff as a JSON patch
`from_bjdata`	create a JSON value from an input in BJData format
`from_bjdata`	create a JSON value from an input in BJData format
`from_bson`
`from_bson`	create a JSON value from an input in BSON format
`from_bson`	create a JSON value from an input in BSON format
`from_bson`
`from_cbor`
`from_cbor`	create a JSON value from an input in CBOR format
`from_cbor`	create a JSON value from an input in CBOR format
`from_cbor`
`from_msgpack`
`from_msgpack`	create a JSON value from an input in MessagePack format
`from_msgpack`	create a JSON value from an input in MessagePack format
`from_msgpack`
`from_ubjson`
`from_ubjson`	create a JSON value from an input in UBJSON format
`from_ubjson`	create a JSON value from an input in UBJSON format
`from_ubjson`
`get_allocator`	returns the allocator associated with the container
`iterator_wrapper`	wrapper to access iterator member functions in range-based for
`iterator_wrapper`	wrapper to access iterator member functions in range-based for
`meta`	returns version information on the library
`object`	explicitly create an object from an initializer list
`parse`
`parse`	deserialize from a compatible input
`parse`	deserialize from a pair of character iterators
`sax_parse`	generate SAX events
`sax_parse`	generate SAX events
`sax_parse`	generate SAX events
`to_bjdata`	create a BJData serialization of a given JSON value
`to_bjdata`	create a BJData serialization of a given JSON value
`to_bjdata`	create a BJData serialization of a given JSON value
`to_bson`	create a BSON serialization of a given JSON value
`to_bson`	create a BSON serialization of a given JSON value
`to_bson`	create a BSON serialization of a given JSON value
`to_cbor`	create a CBOR serialization of a given JSON value
`to_cbor`	create a CBOR serialization of a given JSON value
`to_cbor`	create a CBOR serialization of a given JSON value
`to_msgpack`	create a MessagePack serialization of a given JSON value
`to_msgpack`	create a MessagePack serialization of a given JSON value
`to_msgpack`	create a MessagePack serialization of a given JSON value
`to_ubjson`	create a UBJSON serialization of a given JSON value
`to_ubjson`	create a UBJSON serialization of a given JSON value
`to_ubjson`	create a UBJSON serialization of a given JSON value

Friends

|===

Name	Description
`operator>>`	deserialize from stream
`operator<<`	deserialize from stream
`operator>>`	serialize to stream
`operator<<`	serialize to stream
`swap`	exchanges the values
`exception`	general exception of the `basic_json` class
`serializer`
`json_pointer`

Non-Member Functions

Name	Description
`operator<<`	deserialize from stream
`operator>>`	serialize to stream
`to_string`	user-defined to_string function for JSON values

Description

a class to store JSON values


@invariant The member variables @a m_value and @a m_type have the following
relationship:
- If `m_type == value_t::object`, then `m_value.object != nullptr`.
- If `m_type == value_t::array`, then `m_value.array != nullptr`.
- If `m_type == value_t::string`, then `m_value.string != nullptr`.
The invariants are checked by member function assert_invariant().

@note ObjectType trick from https://stackoverflow.com/a/9860911

nlohmann::basic_json

Synopsis

Base Classes

Types

Member Functions

Static Member Functions

Friends

Non-Member Functions

Description

Created with MrDocs