_parse_autolev_antlr.py 1.7 KB

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  1. from importlib.metadata import version
  2. from sympy.external import import_module
  3. autolevparser = import_module('sympy.parsing.autolev._antlr.autolevparser',
  4. import_kwargs={'fromlist': ['AutolevParser']})
  5. autolevlexer = import_module('sympy.parsing.autolev._antlr.autolevlexer',
  6. import_kwargs={'fromlist': ['AutolevLexer']})
  7. autolevlistener = import_module('sympy.parsing.autolev._antlr.autolevlistener',
  8. import_kwargs={'fromlist': ['AutolevListener']})
  9. AutolevParser = getattr(autolevparser, 'AutolevParser', None)
  10. AutolevLexer = getattr(autolevlexer, 'AutolevLexer', None)
  11. AutolevListener = getattr(autolevlistener, 'AutolevListener', None)
  12. def parse_autolev(autolev_code, include_numeric):
  13. antlr4 = import_module('antlr4')
  14. if not antlr4 or not version('antlr4-python3-runtime').startswith('4.11'):
  15. raise ImportError("Autolev parsing requires the antlr4 Python package,"
  16. " provided by pip (antlr4-python3-runtime)"
  17. " conda (antlr-python-runtime), version 4.11")
  18. try:
  19. l = autolev_code.readlines()
  20. input_stream = antlr4.InputStream("".join(l))
  21. except Exception:
  22. input_stream = antlr4.InputStream(autolev_code)
  23. if AutolevListener:
  24. from ._listener_autolev_antlr import MyListener
  25. lexer = AutolevLexer(input_stream)
  26. token_stream = antlr4.CommonTokenStream(lexer)
  27. parser = AutolevParser(token_stream)
  28. tree = parser.prog()
  29. my_listener = MyListener(include_numeric)
  30. walker = antlr4.ParseTreeWalker()
  31. walker.walk(my_listener, tree)
  32. return "".join(my_listener.output_code)