[xquery-talk] string manipulation

[John Snelson]

Michael Kay wrote:
>>>>replace("book/title/author", "/.*?$", "")
>>>
>>>  Does this garantee to return "book/title" and not "book" ?  The
>>>longuest match would win, doesn't it ?  Personally, I'd use 
>>
>>the regexp
>>
>>>'/[^/]*$'.  BTW, why the '?' after the '*' ?
>>
>>"*?" is a reluctant version of the "*" quantifier, meaning it matches 
>>the shortest sequence, rather than the longest. My regular expression 
>>works because of this - but yours will work as well.
> 
> 
> No, I don't think that "/.*?$" does work. The distinction between .* and .*?
> is that given several matches starting _at the same position_, .* will
> choose the longest while .*? chooses the shortest. But it won't cause
> backtracking to try and find a different match for the "/". 

I guess I didn't fully understand reluctant quantifiers then. Thanks for 
clarifying that.

John

-- 
John Snelson, Berkeley DB XML Engineer
Sleepycat Software, Inc
http://www.sleepycat.com

Contracted to Sleepycat through Parthenon Computing Ltd
http://blog.parthcomp.com/dbxml