Hello,
I am trying to subsitute a '""' pattern in '\"\"' namely escape 2
consecutives double quotes:
* *In Python interpreter:*
$ python
Python 2.7.1rc1 (r271rc1:86455, Nov 16 2010, 21:53:40)
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> expression = *' "" '*
>>> re.subn(*r'([^\\])?"', r'\1\\"', expression*)
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/home/karim/build/python/install/lib/python2.7/re.py", line
162, in subn
return _compile(pattern, flags).subn(repl, string, count)
File "/home/karim/build/python/install/lib/python2.7/re.py", line
278, in filter
return sre_parse.expand_template(template, match)
File "/home/karim/build/python/install/lib/python2.7/sre_parse.py",
line 787, in expand_template
raise error, "unmatched group"
sre_constants.error: unmatched group
But if I remove '?' I get the following:
>>> re.subn(r'([^\\])"', r'\1\\"', expression)
(' \\"" ', 1)
Only one substitution..._But this is not the same REGEX._ And the
count=2 does nothing. By default all occurrence shoul be substituted.
* *On linux using my good old sed command, it is working with my '?'
(0-1 match):*
*$* echo *' "" '* | sed *'s/\([^\\]\)\?"/\1\\"/g*'*
\"\"
*Indeed what's the matter with RE module!?*
*Any idea will be welcome!
Regards
Karim*
*
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