Subject: Re: [xsl] Get the duplicates in a list From: "David Birnbaum djbpitt@xxxxxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> Date: Fri, 3 Jan 2025 15:22:49 -0000 |
Off topic, but following a train of thought: Was there a particular reason behind the design decision that XPath *if* expressions would require an *else* clause? On Jan 3, 2025, at 9:51b/AM, Bauman, Syd s.bauman@xxxxxxxxxxxxxxxx <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx> wrote: o;? > b& why empty-string-and-discard rather than just empty sequence? [paraphrased] Because I didnbt think of it! Thanks for the improvement p ------------------------------------------------------------------------ Are there significant advantages to your suggestions over the following? ( ( for $f in $fieldnames return if ( count( $fieldnames[ . eq $f ] ) gt 1 ) then $f else '' ) => distinct-values() )[. ne ''] I admit it is not simple, but strikes me as simpler. (Note that instead of the null string, one could use any string that is guaranteed not to be a value. I often like bbb (U+241C) or bbb (U+2205) for this kind of thing. One could also probably use a test on that bifb that only looked at preceding or following values of $fieldnames, which some folks might find more readable.) I would hope that the map:merge is ensured to be more efficient than that count($fieldnames[. eq $f]) gt 1 but I am not good at expression complexity in O.. terms. And in the end with advanced XQuery engines it is all thrown at a query optimizer/rewriter that might optimize the expression in a way not comparable to the originable one anyway. I don't get the else '' part to later have to get rid of those with [. ne ''], why can't you simply use else () to return the empty sequence? XSL-List info and archiveEasyUnsubscribe (by email) XSL-List info and archiveEasyUnsubscribe (by email)
Current Thread |
---|
|
<- Previous | Index | Next -> |
---|---|---|
Re: [xsl] Get the duplicates in a l, Bauman, Syd s.bauman | Thread | Re: [xsl] Get the duplicates in a l, Michael Kay michaelk |
Re: [xsl] Get the duplicates in a l, Bauman, Syd s.bauman | Date | Re: [xsl] Get the duplicates in a l, Michael Kay michaelk |
Month |