.. index:: single: json_graph_protocol
.. _json_graph_protocol/0:

.. rst-class:: right

**protocol**

``json_graph_protocol``
=======================

JSON Graph Format v2 parser and generator protocol.

| **Availability:** 
|    ``logtalk_load(json_graph(loader))``

| **Author:** Paulo Moura
| **Version:** 1:0:0
| **Date:** 2026-07-03

| **Compilation flags:**
|    ``static``


| **Dependencies:**
|   (none)


| **Remarks:**
|    (none)

| **Inherited public predicates:**
|    (none)

.. contents::
   :local:
   :backlinks: top

Public predicates
-----------------

.. index:: parse/2
.. _json_graph_protocol/0::parse/2:

``parse/2``
^^^^^^^^^^^

Parses the graph contents read from the given source (``codes(List)``, ``stream(Stream)``, ``file(Path)``, ``chars(List)``, ``atom(Atom)``, or ``object(Object)``) into a list of canonical graph terms. Fails if the contents cannot be parsed.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``parse(Source,Terms)``
| **Mode and number of proofs:**
|    ``parse(++compound,--list)`` - ``one_or_error``

| **Exceptions:**
|    ``Source`` is a variable:
|        ``instantiation_error``
|    ``Source`` is neither a variable nor a valid JSON graph source term:
|        ``domain_error(json_graph_source,Source)``
|    ``Source`` is ``object(Object)`` but ``Object`` does not conform to the graph data protocol:
|        ``domain_error(json_graph_source,Source)``


------------

.. index:: generate/2
.. _json_graph_protocol/0::generate/2:

``generate/2``
^^^^^^^^^^^^^^

Generates the graph contents using the representation specified in the first argument (``codes(List)``, ``stream(Stream)``, ``file(Path)``, ``chars(List)``, ``atom(Atom)``, or ``object(Object)``) for the list of canonical graph terms in the second argument.

| **Compilation flags:**
|    ``static``

| **Template:**
|    ``generate(Sink,Terms)``
| **Mode and number of proofs:**
|    ``generate(+compound,++list)`` - ``one_or_error``

| **Exceptions:**
|    ``Sink`` is a variable:
|        ``instantiation_error``
|    ``Sink`` is neither a variable nor a valid JSON graph sink term:
|        ``domain_error(json_graph_sink,Sink)``
|    ``Terms`` is neither a variable nor a valid list of canonical graph terms:
|        ``domain_error(json_graph_terms,Terms)``


------------

Protected predicates
--------------------

(none)

Private predicates
------------------

(none)

Operators
---------

(none)