47 lines
833 B
Python
47 lines
833 B
Python
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# -----------------------------------------------------------------------------
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# calclex.py
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# -----------------------------------------------------------------------------
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tokens = (
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'NAME','NUMBER',
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'PLUS','MINUS','TIMES','DIVIDE','EQUALS',
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'LPAREN','RPAREN',
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)
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# Tokens
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t_PLUS = r'\+'
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t_MINUS = r'-'
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t_TIMES = r'\*'
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t_DIVIDE = r'/'
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t_EQUALS = r'='
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t_LPAREN = r'\('
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t_RPAREN = r'\)'
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t_NAME = r'[a-zA-Z_][a-zA-Z0-9_]*'
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def t_NUMBER(t):
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r'\d+'
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try:
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t.value = int(t.value)
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except ValueError:
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print "Integer value too large", t.value
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t.value = 0
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return t
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t_ignore = " \t"
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def t_newline(t):
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r'\n+'
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t.lineno += t.value.count("\n")
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def t_error(t):
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print "Illegal character '%s'" % t.value[0]
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t.skip(1)
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# Build the lexer
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import lex
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lex.lex()
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