[Python-Dev] Scanner (original) (raw)

Paul Prescod paulp@ActiveState.com
Sat, 26 May 2001 08:02:08 -0700

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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