Re: [xsl] What does //distinct-values(...) mean?

["Martin Honnen martin.honnen@xxxxxx" <xsl-list-service@xxxxxxxxxxxxxxxxxxxxxx>]

Am 08.04.2020 um 14:19 schrieb Costello, Roger L. costello@xxxxxxxxx:
> Hi Folks,
>
> I executed this XPath query in Oxygen:
>
> //distinct-values(//Row[matches(Advertiser, 'TS3', 'i')]/Subscribers)
>
> The two slashes at the beginning were an accident. At the bottom of the
screen Oxygen shows the matches. All of a sudden it showed 111,000 matches,
then a moment later 438,000 matches, and then finally 525,946 matches.
> "Yikes!" I thought, "What is going on? There is supposed to be around 17
matches. How can there be half a million matches?"
> Then I saw the two slashes at the start.
>
> "Hmm, what is the meaning of two slashes preceding the distinct-values
function?" I thought.
> So, I ask you: what is the meaning of two slashes preceding the
distinct-values function? Why does its evaluation result in so many matches?

// is short for /descendant-or-self::node()/ so
  //distinct-values(//Row[matches(Advertiser, 'TS3', 'i')]/Subscribers)
is
  /descendant-or-self::node()/distinct-values(//Row[matches(Advertiser,
'TS3', 'i')]/Subscribers)
meaning it returns
  distinct-values(//Row[matches(Advertiser, 'TS3', 'i')]/Subscribers)
as many times as the document has any nodes selectable by
/descendant-or-self::node().