Ok, I’ve found a way, see below.

But maybe someone has some nice lua (or other) tricks to share… (I’m not sure accessing t.dt[1] is particularly safe when operating on nested structures.)

Best,

Denis

\startbuffer[test]

<?xml version="1.0" encoding="UTF-8"?>

<doc>

<chapter>

    <title>A short title</title>

    <p>asdf asdf asdf jklö jklö jklö</p>

  </chapter>

  <chapter>

    <title>A longer title bla bla bla bla bla bla bla bla</title>

    <p>

    asdf asdf asdf jklö jklö jklö

    </p>

  </chapter>

</doc>

\stopbuffer

\startxmlsetups xml:test

                \xmlsetsetup{#1}{*}{-}

                \xmlsetsetup{#1}{doc|chapter|p}{xml:*}

\stopxmlsetups

\xmlregisterdocumentsetup{test}{xml:test}

\startxmlsetups xml:doc

                               \xmlflush{#1}

\stopxmlsetups

\setuphead[chapter][expansion=yes] % make sure the stuff gets expanded on time

\startxmlsetups xml:chapter

                \startchapter

                               [

                                               title={\xmlfilter{#1}{/title/command(xml:chapter:title)}},

                                               marking={\xmlfilter{#1}{/title/command(xml:chapter:title:marking)}},

                               ]

                               \xmlflush{#1}

                \stopchapter

\stopxmlsetups

\startxmlsetups xml:p

                \xmlflush{#1}\par

\stopxmlsetups

\startluacode

                function xml.functions.getMarking(t)

_,n = t.dt[1]:gsub("%S+","")

                if n > 10 then

                  local words = {}

                  for word in t.dt[1]:gmatch("%S+") do table.insert(words, word) end

                  local resWords = {}

                  resWords =  { unpack( words, 1, 7 ) }

res = table.concat(resWords, " ") .. " …"

                else

                  res = t.dt[1]

                end

                context(res)

                end

\stopluacode

\startxmlsetups xml:chapter:title:marking

                \xmlfunction{#1}{getMarking}

\stopxmlsetups

\startxmlsetups xml:chapter:title

                \xmlflush{#1}

\stopxmlsetups

\setupheadertexts[chapter]

\starttext

\xmlprocessbuffer{test}{test}{}

\stoptext

Von: denis.maier@unibe.ch <denis.maier@unibe.ch>
Gesendet: Montag, 11. September 2023 16:47
An: ntg-context@ntg.nl
Betreff: [NTG-context] XML: flush to lua function

Hi,

I have the following xml setup with a lua function:

\startluacode

                function markingLength(s)

                _,n = s:gsub("%S+","")

if n > 3 then

                context("yes" .. " …") else context("no") end

                end

\stopluacode

\startxmlsetups xml:ink:ink-title:marking

                %\ctxlua{markingLength(\xmlflush{#1})}  % does not work

                \ctxlua{markingLength{"1 2 3 4"}}

\stopxmlsetups

While the function works, I cannot use xmlflush here. How can I properly pass the xml content to the lua function?

Best,

Denis