On Sat, 17 Oct 2020 at 12:02, Hans Hagen
On 10/17/2020 12:16 AM, mf wrote:
(sorry, I sent it before refining it)
Il 16/10/20 20:57, Jano Kula ha scritto:
Hello!
Processing XML I want to manipulate content of XML elements inside Lua.
I can define the Lua function xml.functions.name http://xml.functions.name(t), where processing happens, and use the command \xmlfunction{#1}{name} to pass the current node #1from ctx to lua as described in the xml-mkiv.pdf manual. To access the element content xml.text(t,"/element") Lua function is used.
However, using the same function xml.text("#1",/element) directly inside Lua doesn't work for me. Node #1 is available, but not the content of /element.
In your lua fragment, node #1 is available as "xml:name::4" or "xml:name::6", but not as a lua table.
when you're at the lua end you can use lxml.getid to access that node, assuming that you somehow pass #1 (being a string)
When node #1 is passed to a \xmlfunction, the function gets a lua table as argument.
To write direct lua code instead of a xmlfunction you'd need a function to transform those "xml:name::..." into the lua tables representing the xml elements in the xml tree.
Which is what \xmlfunction does, so I wouldn't expect any performance gain.
actually one has the same function at the lua end, so once you passed the node id you can use
xml.first(lxml.getid("xml:name::4"),"foo/bar")
and alike (the lxml.* function pipe back to tex)
Hans
Hello, just finished the exploration of the \xmlfunction definition based on Massi's advice when Hans' answer arrived. This is the working code: \startluacode local node = "#1" local content = xml.text(*lxml.getid(*"#1"*)*,"/color") context.par() context("node: ") context(node) context.par() context("lua: ") context(content) \stopluacode Added a note to XML Lua https://wiki.contextgarden.net/XML_Lua wiki page. I do understand the code better now, thank you. Jano