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////
Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
Copyright (c) 2025 Dmitry Arkhipov (grisumbras@yandex.ru)
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Official repository: https://github.com/boostorg/json
////
= Serializing
Serialization is the process where a JSON document represented in memory by
a <<ref_value>> is turned into a sequence of characters. The library provides
the following free functions and types for serialization:
.Serialization Functions and Types
|===
|Name|Description
| <<ref_operator_lt_lt>>
| Serialize a <<ref_value>>, <<ref_array>>, <<ref_object>>, or <<ref_string>>
to a {std_ostream}.
| <<ref_serialize>>
| Return a {std_string} representing a serialized <<ref_value>>, <<ref_array>>,
<<ref_object>>, or <<ref_string>>.
| <<ref_serializer>>
| A stateful object which may be used to efficiently serialize one or more
instances of <<ref_value>>, <<ref_array>>, <<ref_object>>, or <<ref_string>>.
|===
To facilitate debugging and ease of output, library container types may be
written to standard output streams using the stream operator:
[source]
----
include::../../../test/doc_serializing.cpp[tag=doc_serializing_1,indent=0]
----
The <<ref_serialize>> function converts a <<ref_value>> into a {std_string}:
[source]
----
include::../../../test/doc_serializing.cpp[tag=doc_serializing_2,indent=0]
----
In situations where serializing a <<ref_value>> in its entirety is inefficient
or even impossible, <<ref_serializer>> can be used to serialize a <<ref_value>>
incrementally. This may be done for a variety of reasons, such as to avoid
buffering the entire output, or to ensure that a fixed amount of work is
performed in each cycle. Instances of <<ref_serializer>> maintain an output
state using internal dynamically allocated structures, with an interface to
retrieve successive buffers of the serialized output into a caller provided
buffer. Here is an example, demonstrating how <<ref_operator_lt_lt>> may be
implemented using a <<ref_serializer>>:
[source]
----
include::../../../include/boost/json/impl/serialize.ipp[tag=example_operator_lt_lt,indent=0]
----
As with the parser, the serializer may be reused by calling
<<ref_serializer_reset>>. This sets up the object to serialize a new instance
and retains previously allocated memory. This can result in performance
improvements when multiple variables are serialized.