API Reference
=============

Lark
----

.. autoclass:: lark.Lark
    :members: open, parse, save, load

**Using Unicode character classes with regex**

Python's builtin `re` module has a few persistent known bugs and also won't parse
advanced regex features such as character classes.
With `pip install lark-parser[regex]`, the `regex` module will be installed alongside `lark` and can act as a drop-in replacement to `re`.

Any instance of `Lark` instantiated with `regex=True` will now use the `regex` module instead of `re`.

For example, we can now use character classes to match PEP-3131 compliant Python identifiers.

Example:
    ::

        from lark import Lark
        >>> g = Lark(r"""
                            ?start: NAME
                            NAME: ID_START ID_CONTINUE*
                            ID_START: /[\p{Lu}\p{Ll}\p{Lt}\p{Lm}\p{Lo}\p{Nl}_]+/
                            ID_CONTINUE: ID_START | /[\p{Mn}\p{Mc}\p{Nd}\p{Pc}·]+/
                        """, regex=True)

        >>> g.parse('வணக்கம்')
        'வணக்கம்'

Tree
----

.. autoclass:: lark.Tree
    :members: pretty, find_pred, find_data, iter_subtrees,
        iter_subtrees_topdown

Token
-----

.. autoclass:: lark.Token

Transformer, Visitor & Interpreter
---------------------------------

See :doc:`visitors`.

UnexpectedInput
---------------

.. autoclass:: lark.exceptions.UnexpectedInput
    :members: get_context, match_examples

.. autoclass:: lark.exceptions.UnexpectedToken

.. autoclass:: lark.exceptions.UnexpectedCharacters

ParserPuppet
------------

.. autoclass:: lark.parsers.lalr_puppet.ParserPuppet
    :members: choices, feed_token, copy, pretty, resume_parse