value

The type used to represent any JSON value.

Synopsis

Defined in header <boost/json/value.hpp>

class value

Types

Name	Description
allocator_type	The type of Allocator returned by `get_allocator`.

Member Functions

Name	Description
as_array	Return a reference to the underlying `array`, or throw an exception. —
as_bool	Return a reference to the underlying `bool`, or throw an exception. — Return the underlying `bool`, or throw an exception.
as_double	Return a reference to the underlying `double`, or throw an exception. — Return the underlying `double`, or throw an exception.
as_int64	Return a reference to the underlying `std::int64_t`, or throw an exception. — Return the underlying `std::int64_t`, or throw an exception.
as_object	Return a reference to the underlying `object`, or throw an exception. —
as_string	Return a reference to the underlying `string`, or throw an exception. —
as_uint64	Return a reference to the underlying `std::uint64_t`, or throw an exception. — Return the underlying `std::uint64_t`, or throw an exception.
at	Access an element, with bounds checking.
at_pointer	Access an element via JSON Pointer.
emplace_array	Return a reference to an `array`, changing the kind and replacing the contents.
emplace_bool	Return a reference to a `bool`, changing the kind and replacing the contents.
emplace_double	Return a reference to a `double`, changing the kind and replacing the contents.
emplace_int64	Return a reference to a `std::int64_t`, changing the kind and replacing the contents.
emplace_null	Change the kind to null, discarding the previous contents.
emplace_object	Return a reference to an `object`, changing the kind and replacing the contents.
emplace_string	Return a reference to a `string`, changing the kind and replacing the contents.
emplace_uint64	Return a reference to a `std::uint64_t`, changing the kind and replacing the contents.
find_pointer	Access an element via JSON Pointer.
get_allocator	Return the associated `memory_resource`.
get_array	Return a reference to the underlying `array`, without checking. —
get_bool	Return a reference to the underlying `bool`, without checking. — Return the underlying `bool`, without checking.
get_double	Return a reference to the underlying `double`, without checking. — Return the underlying `double`, without checking.
get_int64	Return a reference to the underlying `std::int64_t`, without checking. — Return the underlying `std::int64_t`, without checking.
get_object	Return a reference to the underlying `object`, without checking. —
get_string	Return a reference to the underlying `string`, without checking. —
get_uint64	Return a reference to the underlying `std::uint64_t`, without checking. — Return the underlying `std::uint64_t`, without checking.
if_array	Return an `array` pointer if this is an array, else return `nullptr`
if_bool	Return a `bool` pointer if this is a boolean, else return `nullptr`
if_double	Return a `double` pointer if this is a double, else return `nullptr`
if_int64	Return an `int64_t` pointer if this is a signed integer, else return `nullptr`
if_object	Return an `object` pointer if this is an object, else return `nullptr`
if_string	Return a `string` pointer if this is a string, else return `nullptr`
if_uint64	Return a `uint64_t` pointer if this is an unsigned integer, else return `nullptr`
is_array	Return `true` if this is an array.
is_bool	Return `true` if this is a bool.
is_double	Return `true` if this is a double.
is_int64	Return `true` if this is a signed integer.
is_null	Returns true if this is a null.
is_number	Returns true if this is a number.
is_object	Return `true` if this is an object.
is_primitive	Returns true if this is not an array or object.
is_string	Return `true` if this is a string.
is_structured	Returns true if this is an array or object.
is_uint64	Return `true` if this is a unsigned integer.
kind	Returns the kind of this JSON value.
operator=	Assignment. — Copy assignment. — Move assignment.
set_at_pointer	Set an element via JSON Pointer.
storage	Return the memory resource associated with the value.
swap	Swap the given values.
to_number	Return the stored number cast to an arithmetic type.
value [constructor]	Default constructor. — Constructor. — Pilfer constructor. — Copy constructor. — Move constructor. — Construct a null. — Construct a bool. — Construct a `std::int64_t`. — Construct a `std::uint64_t`. — Construct a `double`. — Construct a `string`. — Construct an `array`. — Construct an `object`. — Construct from an initializer-list.
~value [destructor]	Destructor.

Friends

Name	Description
hash_value	Helper for `boost::hash` support.
operator==	Return `true` if two values are equal.
operator!=	Return `true` if two values are not equal.
operator<<	Serialize `value` to an output stream.
operator>>	Parse `value` from an input stream.
swap	Swap the given values.

Description

This is a Regular type which works like a variant of the basic JSON data types: array, object, string, number, boolean, and null.

Thread Safety

Distinct instances may be accessed concurrently. Non-const member functions of a shared instance may not be called concurrently with any other member functions of that instance.

Convenience header <boost/json.hpp>