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Re: [xsl] Cheaper to prepend or append an item to a sequence?

2011-02-22 14:00:59
On Tue, Feb 22, 2011 at 8:32 AM, Michael Kay <mike(_at_)saxonica(_dot_)com> 
wrote:

Even with a forward-chained list, you can implement append without copying
if you choose, at least for the first append operation to a given list
(which 9 times out of 10 will be the only append operation).

How is that?  If I have X=[1,2,3] ; Y=X ; Z=Y++[4]

How can Z append Y without copying it first?  You of course cannot
modify Y in FP at all (which you know), much less w/o changing X.

I'm confused.

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