test/lex_re3.py


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# lex_re3.py
#
# Regular expression rule matches empty string

import sys
if ".." not in sys.path: sys.path.insert(0,"..")

import ply.lex as lex

tokens = [
    "PLUS",
    "MINUS",
    "NUMBER",
    "POUND",
    ]

t_PLUS = r'\+'
t_MINUS = r'-'
t_NUMBER = r'(\d+)'
t_POUND = r'#'

def t_error(t):
    pass


lex.lex()