45 lines
700 B
Python
45 lines
700 B
Python
# lex_state_try.py
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#
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# Declaration of a state for which no rules are defined
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import sys
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if ".." not in sys.path: sys.path.insert(0,"..")
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import ply.lex as lex
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tokens = [
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"PLUS",
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"MINUS",
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"NUMBER",
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]
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states = (('comment', 'exclusive'),)
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t_PLUS = r'\+'
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t_MINUS = r'-'
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t_NUMBER = r'\d+'
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t_ignore = " \t"
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# Comments
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def t_comment(t):
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r'/\*'
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t.lexer.begin('comment')
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print("Entering comment state")
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def t_comment_body_part(t):
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r'(.|\n)*\*/'
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print("comment body %s" % t)
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t.lexer.begin('INITIAL')
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def t_error(t):
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pass
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t_comment_error = t_error
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t_comment_ignore = t_ignore
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lex.lex()
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data = "3 + 4 /* This is a comment */ + 10"
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lex.runmain(data=data)
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