44 lines
1.3 KiB
Python
44 lines
1.3 KiB
Python
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# Copyright 2006 Google, Inc. All Rights Reserved.
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# Licensed to PSF under a Contributor Agreement.
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"""Export the Python grammar and symbols."""
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# Python imports
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import os
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# Local imports
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from .pgen2 import token
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from .pgen2 import driver
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from . import pytree
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# The grammar file
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_GRAMMAR_FILE = os.path.join(os.path.dirname(__file__), "Grammar.txt")
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_PATTERN_GRAMMAR_FILE = os.path.join(os.path.dirname(__file__),
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"PatternGrammar.txt")
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class Symbols(object):
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def __init__(self, grammar):
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"""Initializer.
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Creates an attribute for each grammar symbol (nonterminal),
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whose value is the symbol's type (an int >= 256).
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"""
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for name, symbol in grammar.symbol2number.items():
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setattr(self, name, symbol)
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python_grammar = driver.load_packaged_grammar("lib2to3", _GRAMMAR_FILE)
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python_symbols = Symbols(python_grammar)
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python_grammar_no_print_statement = python_grammar.copy()
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del python_grammar_no_print_statement.keywords["print"]
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python_grammar_no_print_and_exec_statement = python_grammar_no_print_statement.copy()
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del python_grammar_no_print_and_exec_statement.keywords["exec"]
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pattern_grammar = driver.load_packaged_grammar("lib2to3", _PATTERN_GRAMMAR_FILE)
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pattern_symbols = Symbols(pattern_grammar)
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