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(8/243) 2489 - positive lookahead does only work in the end

the positive look ahead expression (?= ) seems to be
working only in the end of the expression. For ex. if
an expression for some words inside tags is needed we
expect this to do the work:
(?= <(\[^>\]\*))thewordIsearch(?=(\[^<\]\*)>)

it doesn't work, but of course if I remove look
ahead: "(<(\[^>\]\*))thewordIsearch(?=(\[^<\]\*)>)" it
works, but it doesnt hide the text before the word I
search for.

Submitted	velniava - 2005-12-05 15:18:12	Assigned
Priority	5	Labels	search and replace
Status	open	Group	minor bug
Resolution	None

Comments

2007-02-14 21:25:57 rschwenn	Logged In: YES user_id=1486645 Originator: NO Sill valid for jEdit 4.3pre9. SUN JRE 1.5.0_11 WinXP SP2
2010-03-27 18:37:04 kerik-sf	I'm by no mean a regexp expert (far from it), but shouldn't one use a positive look-behind ? At first, I tried (?<=<(\[^>\]\))bonjour(?=(\[^<\]\)>) but got a java.util.regex.PatternSyntaxException: Look-behind group does not have an obvious maximum length near index 11 (?<=<(\[^>\]\))bonjour(?=(\[^<\]\)>) So I added an explicit bound and found that (?<=<(\[^>\]{0,100}?))bonjour(?=(\[^<\]\*)>) works
2010-03-27 18:37:05 kerik-sf	- status: open --> pending-invalid
2010-03-27 18:51:34 kerik-sf	- status: pending-invalid --> open
2010-03-27 18:51:34 kerik-sf	my suggestion doesn't work on inputs like this : "<lebonjour>" while it should \! It's a bug in the regex engine, see : http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6284152
2010-03-27 18:57:30 kerik-sf	the workaround suggested in the sun bug report works : "bonjour(?<=<(\[^>\]{0,100}bonjour))(?=(\[^<\]\*)>)". Attached is a beanshell to demonstrate the problem with java.util.regex : open it and run it. The second alternative works, but the first one doesn't.
2010-03-27 18:57:36 kerik-sf	beanshell to run on itself test_positive_lookahead.bsh (686B)