id	summary	reporter	owner	description	type	status	milestone	component	version	severity	resolution	keywords	cc
4309	Negative lookbehind assertion error	anonymous	John Maddock	"As soon as you include an OR-expression inside a negative lookbehind assertion, you get wrong results. Not sure if this is a bug, but I've tested this with multiple engines and I get different results.

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Regex:
(?<!foo|bar) \(

String:
test bar (

NO MATCH (expected)
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Regex:
(?<!food|bar) \(

String:
test bar (

MATCH (NOT expected)
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Regex:
(?<!fo|bar) \(

String:
test bar (

MATCH (NOT expected)
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This really makes it hard to match certain strings :("	Bugs	closed	Boost 1.43.0	regex	Boost 1.43.0	Problem	fixed