Hi, hope this is comprehensible without a full example: I want to do some operations on my xml, and that's easier to do in Lua. However, I cannot find how to filter my results and pass them on to a command. In TeX, I would do this: \startxmlsetups xml:a \xmlfilter{#1}{/b/command(xml:command:b)} \stopxmlsetups \startxmlsetups xml:command:b \xmlconcat{#1}{/}\par \stopxmlsetups How would I do the same thing in Lua? Here's what I tried: function xml.functions.a(t) local b = lxml.filter(lxml.id(t), "/b") process(b) end function process(t) xml.xprint(t) end but that doesn't work yet, I get no results printed. So my question: what would be the right syntax in Lua? (And bonus points for: what is the equivalent of \xmlconcat ?) All best Thomas