1# lex_re3.py
2#
3# Regular expression rule matches empty string
4
5import sys
6if ".." not in sys.path: sys.path.insert(0,"..")
7
8import ply.lex as lex
9
10tokens = [
11    "PLUS",
12    "MINUS",
13    "NUMBER",
14    "POUND",
15    ]
16
17t_PLUS = r'\+'
18t_MINUS = r'-'
19t_NUMBER = r'(\d+)'
20t_POUND = r'#'
21
22def t_error(t):
23    pass
24
25
26
27lex.lex()
28
29
30