.TH "cereal::JSONOutputArchive" 3 "Mon Oct 26 2026 02:55:37" "cereal" \" -*- nroff -*-
.ad l
.nh
.SH NAME
cereal::JSONOutputArchive \- An output archive designed to save data to JSON\&.  

.SH SYNOPSIS
.br
.PP
.PP
\fR#include </home/build/include/cereal/archives/json\&.hpp>\fP
.PP
Inherits \fBcereal::OutputArchive< JSONOutputArchive >\fP, and \fBcereal::traits::TextArchive\fP\&.
.SS "Classes"

.in +1c
.ti -1c
.RI "class \fBOptions\fP"
.br
.RI "A class containing various advanced options for the JSON archive\&. "
.in -1c
.SS "Public Member Functions"

.PP
.RI "\fBCommon Functionality\fP"
.br
Common use cases for directly interacting with an \fBJSONOutputArchive\fP 
.PP
.in +1c
.in +1c
.ti -1c
.RI "\fBJSONOutputArchive\fP (std::ostream &stream, \fBOptions\fP const &options=\fBOptions::Default\fP())"
.br
.RI "Construct, outputting to the provided stream\&. "
.ti -1c
.RI "\fB~JSONOutputArchive\fP () \fBCEREAL_NOEXCEPT\fP"
.br
.RI "Destructor, flushes the JSON\&. "
.ti -1c
.RI "void \fBsaveBinaryValue\fP (const void *data, size_t size, const char *name=nullptr)"
.br
.RI "Saves some binary data, encoded as a base64 string, with an optional name\&. "
.in -1c
.in -1c

Public Member Functions inherited from \fBcereal::OutputArchive< JSONOutputArchive >\fP
.in +1c
.ti -1c
.RI "\fBOutputArchive\fP (\fBJSONOutputArchive\fP *const derived)"
.br
.RI "Construct the output archive\&. "
.ti -1c
.RI "\fBOutputArchive\fP & \fBoperator=\fP (\fBOutputArchive\fP const &)=delete"
.br
.ti -1c
.RI "\fBJSONOutputArchive\fP & \fBoperator()\fP (Types &&\&.\&.\&. args)"
.br
.RI "Serializes all passed in data\&. "
.ti -1c
.RI "void \fBserializeDeferments\fP ()"
.br
.RI "Serializes any data marked for deferment using defer\&. "
.ti -1c
.RI "std::uint32_t \fBregisterSharedPointer\fP (const std::shared_ptr< const void > &sharedPointer)"
.br
.RI "Registers a shared pointer with the archive\&. "
.ti -1c
.RI "std::uint32_t \fBregisterPolymorphicType\fP (char const *name)"
.br
.RI "Registers a polymorphic type name with the archive\&. "
.in -1c
.in +1c
.ti -1c
.RI "\fBJSONOutputArchive\fP & \fBoperator&\fP (T &&arg)"
.br
.RI "Serializes passed in data\&. "
.in -1c
.in +1c
.ti -1c
.RI "\fBJSONOutputArchive\fP & \fBoperator<<\fP (T &&arg)"
.br
.RI "Serializes passed in data\&. "
.in -1c

Public Member Functions inherited from \fBcereal::detail::OutputArchiveBase\fP
.in +1c
.ti -1c
.RI "\fBOutputArchiveBase\fP (OutputArchiveBase &&) \fBCEREAL_NOEXCEPT\fP"
.br
.ti -1c
.RI "OutputArchiveBase & \fBoperator=\fP (OutputArchiveBase &&) \fBCEREAL_NOEXCEPT\fP"
.br
.in -1c
.SS "Internal Functionality"
Functionality designed for use by those requiring control over the inner mechanisms of the \fBJSONOutputArchive\fP 
.in +1c
.ti -1c
.RI "void \fBstartNode\fP ()"
.br
.RI "Starts a new node in the JSON output\&. "
.ti -1c
.RI "void \fBfinishNode\fP ()"
.br
.RI "Designates the most recently added node as finished\&. "
.ti -1c
.RI "void \fBsetNextName\fP (const char *name)"
.br
.RI "Sets the name for the next node created with startNode\&. "
.ti -1c
.RI "void \fBsaveValue\fP (bool b)"
.br
.RI "Saves a bool to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (int i)"
.br
.RI "Saves an int to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (unsigned u)"
.br
.RI "Saves a uint to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (int64_t i64)"
.br
.RI "Saves an int64 to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (uint64_t u64)"
.br
.RI "Saves a uint64 to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (double d)"
.br
.RI "Saves a double to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (std::string const &s)"
.br
.RI "Saves a string to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (char const *s)"
.br
.RI "Saves a const char * to the current node\&. "
.ti -1c
.RI "void \fBsaveValue\fP (std::nullptr_t)"
.br
.RI "Saves a nullptr to the current node\&. "
.ti -1c
.RI "template<class T, traits::EnableIf< std::is_same< T, long >::value, !std::is_same< T, int >::value, !std::is_same< T, std::int64_t >::value > = traits::sfinae> void \fBsaveValue\fP (T t)"
.br
.RI "Serialize a long if it would not be caught otherwise\&. "
.ti -1c
.RI "template<class T, traits::EnableIf< std::is_same< T, unsigned long >::value, !std::is_same< T, unsigned >::value, !std::is_same< T, std::uint64_t >::value > = traits::sfinae> void \fBsaveValue\fP (T t)"
.br
.RI "Serialize an unsigned long if it would not be caught otherwise\&. "
.ti -1c
.RI "template<class T, traits::EnableIf< std::is_arithmetic< T >::value, !std::is_same< T, long >::value, !std::is_same< T, unsigned long >::value, !std::is_same< T, std::int64_t >::value, !std::is_same< T, std::uint64_t >::value,(sizeof(T) >=sizeof(long double)||sizeof(T) >=sizeof(long long))> = traits::sfinae> void \fBsaveValue\fP (T const &t)"
.br
.RI "Save exotic arithmetic as strings to current node\&. "
.ti -1c
.RI "void \fBwriteName\fP ()"
.br
.RI "Write the name of the upcoming node and prepare object/array state\&. "
.ti -1c
.RI "void \fBmakeArray\fP ()"
.br
.RI "Designates that the current node should be output as an array, not an object\&. "
.in -1c
.SS "Additional Inherited Members"

.in +1c
.ti -1c
.RI "using \fBis_loading\fP"
.br
.RI "Indicates this archive is not intended for loading\&. "
.in -1c
.in +1c
.ti -1c
.RI "using \fBis_saving\fP"
.br
.RI "Indicates this archive is intended for saving\&. "
.in -1c
.SH "Detailed Description"
.PP 
An output archive designed to save data to JSON\&. 

This archive uses RapidJSON to build serialize data to JSON\&.

.PP
JSON archives provides a human readable output but at decreased performance (both in time and space) compared to binary archives\&.

.PP
JSON archives are only guaranteed to finish flushing their contents upon destruction and should thus be used in an RAII fashion\&.

.PP
JSON benefits greatly from name-value pairs, which if present, will name the nodes in the output\&. If these are not present, each level of the output will be given an automatically generated delimited name\&.

.PP
The precision of the output archive controls the number of decimals output for floating point numbers and should be sufficiently large (i\&.e\&. at least 20) if there is a desire to have binary equality between the numbers output and those read in\&. In general you should expect a loss of precision when going from floating point to text and back\&.

.PP
JSON archives do not output the size information for any dynamically sized structure and instead infer it from the number of children for a node\&. This means that data can be hand edited for dynamic sized structures and will still be readable\&. This is accomplished through the \fBcereal::SizeTag\fP object, which will cause the archive to output the data as a JSON array (e\&.g\&. marked by [] instead of {}), which indicates that the container is variable sized and may be edited\&. 
.SH "Constructor & Destructor Documentation"
.PP 
.SS "cereal::JSONOutputArchive::JSONOutputArchive (std::ostream & stream, \fBOptions\fP const & options = \fR\fBOptions::Default\fP()\fP)\fR [inline]\fP"

.PP
Construct, outputting to the provided stream\&. 
.PP
\fBParameters\fP
.RS 4
\fIstream\fP The stream to output to\&. 
.br
\fIoptions\fP The JSON specific options to use\&. See the \fBOptions\fP struct for the values of default parameters 
.RE
.PP

.SH "Member Function Documentation"
.PP 
.SS "void cereal::JSONOutputArchive::saveBinaryValue (const void * data, size_t size, const char * name = \fRnullptr\fP)\fR [inline]\fP"

.PP
Saves some binary data, encoded as a base64 string, with an optional name\&. This will create a new node, optionally named, and insert a value that consists of the data encoded as a base64 string 
.SS "template<class T, traits::EnableIf< std::is_arithmetic< T >::value, !std::is_same< T, long >::value, !std::is_same< T, unsigned long >::value, !std::is_same< T, std::int64_t >::value, !std::is_same< T, std::uint64_t >::value,(sizeof(T) >=sizeof(long double)||sizeof(T) >=sizeof(long long))> = traits::sfinae> void cereal::JSONOutputArchive::saveValue (T const & t)\fR [inline]\fP"

.PP
Save exotic arithmetic as strings to current node\&. Handles long long (if distinct from other types), unsigned long (if distinct), and long double 
.SS "void cereal::JSONOutputArchive::startNode ()\fR [inline]\fP"

.PP
Starts a new node in the JSON output\&. The node can optionally be given a name by calling setNextName prior to creating the node

.PP
Nodes only need to be started for types that are themselves objects or arrays 
.SS "void cereal::JSONOutputArchive::writeName ()\fR [inline]\fP"

.PP
Write the name of the upcoming node and prepare object/array state\&. Since writeName is called for every value that is output, regardless of whether it has a name or not, it is the place where we will do a deferred check of our node state and decide whether we are in an array or an object\&.

.PP
The general workflow of saving to the JSON archive is:

.PP
.IP "1." 4
(optional) Set the name for the next node to be created, usually done by an NVP
.IP "2." 4
Start the node
.IP "3." 4
(if there is data to save) Write the name of the node (this function)
.IP "4." 4
(if there is data to save) Save the data (with saveValue)
.IP "5." 4
Finish the node 
.PP


.SH "Author"
.PP 
Generated automatically by Doxygen for cereal from the source code\&.