Message 157265 - Python tracker

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In-reply-to
Author	py.user
Recipients	docs@python, ezio.melotti, mrabarnett, py.user
Date	2012年04月01日.08:11:59
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<1333267920.68.0.0890741084259.issue14461@psf.upfronthosting.co.za>

Content
http://docs.python.org/py3k/library/re.html "Note that patterns which start with positive lookbehind assertions will never match at the beginning of the string being searched; you will most likely want to use the search() function rather than the match() function:" >>> re.match(r'(?<=^)abc', 'abc').group() 'abc' >>> re.match(r'(?<=\b)abc', 'abc').group() 'abc' >>> re.match(r'(?<=\A)abc', 'abc').group() 'abc' >>> re.match(r'(?<=\A)abc', 'abc', re.DEBUG).group() assert -1 at at_beginning_string literal 97 literal 98 literal 99 'abc' >>> in some cases match() can match

Content

http://docs.python.org/py3k/library/re.html
"Note that patterns which start with positive lookbehind assertions will never match at the beginning of the string being searched; you will most likely want to use the search() function rather than the match() function:"
>>> re.match(r'(?<=^)abc', 'abc').group()
'abc'
>>> re.match(r'(?<=\b)abc', 'abc').group()
'abc'
>>> re.match(r'(?<=\A)abc', 'abc').group()
'abc'
>>> re.match(r'(?<=\A)abc', 'abc', re.DEBUG).group()
assert -1 
 at at_beginning_string 
literal 97 
literal 98 
literal 99 
'abc'
>>>
in some cases match() can match

History
Date	User	Action	Args
2012年04月01日 08:12:00	py.user	set	recipients: + py.user, ezio.melotti, mrabarnett, docs@python
2012年04月01日 08:12:00	py.user	set	messageid: <1333267920.68.0.0890741084259.issue14461@psf.upfronthosting.co.za>
2012年04月01日 08:12:00	py.user	link	issue14461 messages
2012年04月01日 08:11:59	py.user	create

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