.. include:: links.rst

Viewing Models as JSON
----------------------


Models generated by |TatSu| can be viewed by converting them to a JSON-compatible structure
with the help of ``tatsu.util.asjson()``. The protocol tries to provide the best
representation for common types, and can handle any type using ``repr()``. There are provisions for structures with back-references, so there's no infinite recursion.

.. code:: python

    import json

    print(json.dumps(asjson(model), indent=2))

The ``model``, with richer semantics, remains unaltered.

Conversion to a JSON-compatible structure relies on the protocol defined by
``tatsu.utils.AsJSONMixin``.  The mixin defines a ``__json__(seen=None)``
method that allows classes to define their best translation. You can use ``AsJSONMixin``
as a base class in your own models to take advantage of ``asjson()``, and you can
specialize the conversion by overriding ``AsJSONMixin.__json__()``.

You can also write your own version of ``asjson()`` to handle special cases that are recurrent in your context.