34 lines
529 B
Python
34 lines
529 B
Python
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import sys
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if ".." not in sys.path: sys.path.insert(0,"..")
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from ply import lex, yacc
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t_A = 'A'
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t_B = 'B'
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t_C = 'C'
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tokens = ('A', 'B', 'C')
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the_lexer = lex.lex()
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def t_error(t):
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pass
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def p_error(p):
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pass
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def p_start(t):
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'''start : A nest C'''
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pass
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def p_nest(t):
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'''nest : B'''
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print(t[-1])
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the_parser = yacc.yacc(debug = False, write_tables = False)
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the_parser.parse('ABC', the_lexer)
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the_parser.parse('ABC', the_lexer, tracking=True)
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the_parser.parse('ABC', the_lexer, tracking=True, debug=1)
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