Subject: Re: [xsl] Cheaper to prepend or append an item to a sequence?|
From: iwanttokeepanon <iwanttokeepanon@xxxxxxxxx>
Date: Tue, 22 Feb 2011 14:00:49 -0600
On Tue, Feb 22, 2011 at 8:32 AM, Michael Kay <mike@xxxxxxxxxxxx> 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++ 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.