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Name	Size	Permission	Date
__pycache__	[ DIR ]	drwxr-xr-x	2026-06-08 18:08
__pyinstaller	[ DIR ]	drwxr-xr-x	2026-06-08 18:08
grammars	[ DIR ]	drwxr-xr-x	2026-06-08 18:08
parsers	[ DIR ]	drwxr-xr-x	2026-06-08 18:08
tools	[ DIR ]	drwxr-xr-x	2026-06-08 18:08
LICENSE	1.03 KB	-rw-r--r--	1980-01-01 08:00
__init__.py	744 B	-rw-r--r--	1980-01-01 08:00
ast_utils.py	2.04 KB	-rw-r--r--	1980-01-01 08:00
common.py	2.83 KB	-rw-r--r--	1980-01-01 08:00
exceptions.py	10.68 KB	-rw-r--r--	1980-01-01 08:00
grammar.py	3.35 KB	-rw-r--r--	1980-01-01 08:00
indenter.py	3 KB	-rw-r--r--	1980-01-01 08:00
lark.py	27.09 KB	-rw-r--r--	1980-01-01 08:00
lexer.py	22.98 KB	-rw-r--r--	1980-01-01 08:00
load_grammar.py	52.23 KB	-rw-r--r--	1980-01-01 08:00
parse_tree_builder.py	13.78 KB	-rw-r--r--	1980-01-01 08:00
parser_frontends.py	9.82 KB	-rw-r--r--	1980-01-01 08:00
py.typed	0 B	-rw-r--r--	1980-01-01 08:00
reconstruct.py	3.63 KB	-rw-r--r--	1980-01-01 08:00
tree.py	8.04 KB	-rw-r--r--	1980-01-01 08:00
tree_matcher.py	5.86 KB	-rw-r--r--	1980-01-01 08:00
tree_templates.py	6 KB	-rw-r--r--	1980-01-01 08:00
utils.py	10.73 KB	-rw-r--r--	1980-01-01 08:00
visitors.py	20.6 KB	-rw-r--r--	1980-01-01 08:00

Rename

"""
    Module of utilities for transforming a lark.Tree into a custom Abstract Syntax Tree
"""

import inspect, re
import types
from typing import Optional, Callable

from lark import Transformer, v_args

class Ast:
    """Abstract class

Subclasses will be collected by `create_transformer()`
    """
    pass

class AsList:
    """Abstract class

Subclasses will be instantiated with the parse results as a single list, instead of as arguments.
    """

class WithMeta:
    """Abstract class

Subclasses will be instantiated with the Meta instance of the tree. (see ``v_args`` for more detail)
    """
    pass

def camel_to_snake(name):
    return re.sub(r'(?<!^)(?=[A-Z])', '_', name).lower()

def create_transformer(ast_module: types.ModuleType,
                       transformer: Optional[Transformer]=None,
                       decorator_factory: Callable=v_args) -> Transformer:
    """Collects `Ast` subclasses from the given module, and creates a Lark transformer that builds the AST.

For each class, we create a corresponding rule in the transformer, with a matching name.
    CamelCase names will be converted into snake_case. Example: "CodeBlock" -> "code_block".

Classes starting with an underscore (`_`) will be skipped.

Parameters:
        ast_module: A Python module containing all the subclasses of ``ast_utils.Ast``
        transformer (Optional[Transformer]): An initial transformer. Its attributes may be overwritten.
        decorator_factory (Callable): An optional callable accepting two booleans, inline, and meta,
            and returning a decorator for the methods of ``transformer``. (default: ``v_args``).
    """
    t = transformer or Transformer()

for name, obj in inspect.getmembers(ast_module):
        if not name.startswith('_') and inspect.isclass(obj):
            if issubclass(obj, Ast):
                wrapper = decorator_factory(inline=not issubclass(obj, AsList), meta=issubclass(obj, WithMeta))
                obj = wrapper(obj).__get__(t)
                setattr(t, camel_to_snake(name), obj)

return t