[Python-Dev] Scanner

[Paul Prescod]

What ever happened to the sre Scanner? It seemed like a good idea but it
was not documented and it doesn't work for me. Is it just a case of
nobody got around to the documentation or have we decided against it?

Here's the code that doesn't work for me:

from sre import Scanner

scanner = Scanner([
    (r"[a-zA-Z_]\w*", None),
    (r"\d+\.\d*", None),
    (r"\d+", None),
    (r"=|\+|-|\*|/", None),
    (r"\s+", None),
    ])

tokens, tail = scanner.scan("sum = 3*foo + 312.50 + bar")

Traceback (most recent call last):
  File "junk.py", line 11, in ?
    tokens, tail = scanner.scan("sum = 3*foo + 312.50 + bar")
  File "c:\program files\python21\lib\sre.py", line 254, in scan
    action = self.lexicon[m.lastindex][1]
TypeError: sequence index must be integer

m.lastindex is None
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