[NTG-context] use of preceding-sibling in xmlsetsetup

[massifr at fastwebnet.it]

Here's the (complete) code:

\startbuffer[test]
<text>
  <p class="incipit">Dear list,</p>
  <p class="dopo-incipit">this paragraph should not be indented, because it follows the “incipit”
  of the letter.</p>
  <p>This one and the following ones should be indented.</p>
  <p>You may question whether “Dear list,” should be a paragraph of his own,
  but my text is already formatted like that and I can’t do anything 
  about it.</p>
</text>
\stopbuffer
 
\startxmlsetups xml:somesetups
  \xmlsetsetup{#1}{text}{xml:text}
  \xmlsetsetup{#1}{p}{xml:p}
  \xmlsetsetup{#1}{p[@class='incipit']}{xml:p:noindent}
  % the following lpath expression does not work
  % \xmlsetsetup{#1}{p[reverse-sibling::p[1]/attribute('class') == 'incipit']}{xml:p:noindent}
\stopxmlsetups

\xmlregistersetup{xml:somesetups}

\startxmlsetups xml:text
  \indenting[{yes,first,12pt}]
  \xmlflush{#1}
\stopxmlsetups

\startxmlsetups xml:p
  \doif{\xmlattribute{#1}{reverse-sibling::p[1]}{class}}{incipit}{\noindent}
  \xmlflush{#1}\par
\stopxmlsetups
 
\startxmlsetups xml:p:noindent
  \noindent\xmlflush{#1}\par
\stopxmlsetups

\starttext
  \xmlprocessbuffer{main}{test}{}
\stoptext
 
It's the example of the original message of this thread, with the 
modifications posted in the second message.

In the \startxmlsetups section I tried to put that condition in a
\xmlsetsetup, but I commented it out because it did not work.
 
Here's where I found an example with reverse-sibling:
https://www.mail-archive.com/ntg-context%40ntg.nl/msg77364.html
I was searching for "sibling" in the mailing list archive to see whether
"sibling expressions" had been implemented.

Greetings,
Massi

> > On 10/17/2015 11:19 AM, mf wrote:
> > > "reverse-sibling" is ConTeXt specific and very useful: it's a "reversed
> > > preceding-sibling", so that you find the nearest sibling at index [1].
> > > I've used it successfully in a \doif statement, but I failed in
> > > translating it in a \xmlsetsetup statement, to tell ConTeXt: "this
> > > setup is for an element p whose nearest preceding sibling p has class
> > > 'incipit'".
> > 
> > In that case, why don't you show the code where you've used it 
> > successfully and maybe we can take it from there.
> > 
> > Thomas
> >