BIBR expend as per Input XML using LuaLaTeX

Question

In the XML file cross-links are not expended like 2–5 and final latex should be \citep{B2,B3,B4,B5}.

Any Number should expend in all the cross-links like, if XML coded as 11–18 it should be convert to \citep{B11,B12,B13,B14,B15,B16,B17,B18} (beginning to end). How to get the expected result using LuaLaTeX?

My XML is:

\documentclass{article}
\usepackage{luacode}
\begin{document}
\begin{luacode}
local domobject = require "luaxml-domobject"
local transform = require "luaxml-transform"
sample = [[
<?xml version="1.0" encoding="utf-8"?>
<art>
<title>Scattering of flexural waves an electric current</title>
<para>Smart testing structures are $a+b$ components Reduce acoustic noise used in engineering applications that are capable of sensing or reacting to their environment change <?LuaLaTeX Sample XXX1?> their mechanical properties. in a predictable and desired manner. In addition to carrying mechanical loads, <?LuaLaTeX \hspace{12pt}Abc?> alleviate vibration, reduce acoustic noise, change their mechanical properties as required or monitor their own condition.</para>
<para>The first <xref ref-type="section" rid="Sec1">Section 1</xref> description and correlation between gait impairment and hydrocephalus were made in 1965 by Hakim and Adam (<xref ref-type="bibr" rid="B1">1</xref>). The etiology of idiopathic normal pressure hydrocephalus (iNPH) has not yet been entirely understood (<xref ref-type="bibr" rid="B2">2</xref>&#x02013;<xref ref-type="bibr" rid="B5">5</xref>). In elderly patients, other conditions such as spinal canal stenosis, Parkinson&#x00027;s disease, and polyneuropathy may influence the gait negatively.</para>
</art>]]
local dom = domobject.parse(sample)
local function process_instructions(el)
  for _, child in ipairs(el:get_children()) do
    local ntype = child:get_node_type()
    if ntype == "PI" and child._name=="LuaLaTeX" then
      local text = child._attr[ "_text" ]
      local newel = el:create_element("lualatex-instruction", {text = text})
      child:replace_node(newel)
    end
    if child:is_element() then
      process_instructions(child)
    end
  end
end
process_instructions(dom:root_node())
local transformer = transform.new()
transformer:add_action("title", "\section{@<.>}")
transformer:add_action("para", "@<.>\par")
-- handle the processing instruction
transformer:add_custom_action("lualatex-instruction",
    function(el)
        return el:get_attribute("text")
    end)
transform.print_tex(transformer:process_dom(dom))
\end{luacode*}
\end{document}

I have expected output LaTeX file is:

Smart testing structures are $a+b$ components Reduce acoustic noise used in
engineering applications that are capable of sensing or reacting to their environment change Sample XXX1 their mechanical properties. in a predictable
and desired manner. In addition to carrying mechanical loads,
Abc alleviate
vibration, reduce acoustic noise, change their mechanical properties as required
or monitor their own condition.
The first Section 1 description and correlation between gait impairment and
hydrocephalus were made in 1965 by Hakim and Adam (\citep{B1}). The etiology of idio-
pathic normal pressure hydrocephalus (iNPH) has not yet been entirely under-
stood (\citep{B2,B3,B4,B5}). In elderly patients, other conditions such as spinal canal stenosis,
Parkinson’s disease, and polyneuropathy may influence the gait negatively.

you just assign a Lua string to sample and never use it, so this document has no output. — David Carlisle, Jul 19 '23 at 16:26
@David: Yes and does not know how to get the expect output using lualatex. — Balaji, Jul 19 '23 at 17:49
but there is no standard typeset form for xml. You would have to define how to handle each element and implement the transform to tex. — David Carlisle, Jul 19 '23 at 17:52
@DavidCarlisle: I have updated the question. I know how to get the attribute value from xref. But not any idea expand the attribute values (like B2,B3,B4,B5).. How to get this? — Balaji, Jul 20 '23 at 11:27

score 1 · Accepted Answer · answered Jul 23 '23 at 17:49

So if I understand it correctly, you don't have the numbers that you want to expand explicitly stated as attributes of the xref element, but rather encoded as two separate xref elements:

<xref ref-type="bibr" rid="B2">2</xref>&#x02013;<xref ref-type="bibr" rid="B5">5</xref>

I don't think it is a good idea, but we can try anyway. In this case, you will need some pre-processing of the DOM to detect these cases and convert them to something that can be used in the tranformer library. This code should do that:

-- try to find <xref> followed by dash and another <xref>
-- we then expand rid attributes
for _, xref in ipairs(dom:query_selector("xref[ref-type='bibr']")) do
  local first = xref:get_sibling_node(1)
  local second = xref:get_sibling_node(2)
  if first and second and
     first:is_text() and first:get_text() == "–" and -- next node must be "–" text
     second:is_element() and second:get_element_name() == "xref" -- second element must be <xref>
  then
    local rid1 = xref:get_attribute("rid") or ""
    local rid2 = second:get_attribute("rid") or ""
    local prefix1, number1 = rid1:match("(%a+)(%d+)")
    local prefix2, number2 = rid2:match("(%a+)(%d+)")
    -- expand only if prefixes match each other
    if prefix1 and prefix2 and prefix1 == prefix2 then
      -- expand numbers
      local t = {}
      for i = number1, number2 do
        t[#t+1] = prefix1 .. math.floor(i)
      end
      -- save expanded numbers
      xref:set_attribute("rid", table.concat(t, ","))
      -- remove unnecessary elements
      first:remove_node()
      second:remove_node()
    end
  end
end

It detects <xref> elements followed by dash and another <xref>, sets the expanded ids as the rid attribute, and removes the unnecessary dash and second <xref>. You can then declare this transform rule to convert <xref> with ref-type of bibr to \citep:

transformer:add_action("xref[ref-type='bibr']", "\\citep{@{rid}}")

The @{rid} action will print value of the rid attribute.

This is the translated TeX result:

\section{Scattering of flexural waves an electric current}
Smart testing structures are \$a+b\$ components Reduce acoustic noise used in engineering applications that are capable of sensing or reacting to their environment change  Sample XXX1 their mechanical properties. 
in a predictable and desired manner. In addition to carrying mechanical loads,  \hspace*{12pt}Abc alleviate vibration, reduce acoustic noise, change their mechanical properties as required or monitor their own condition.\par
The first Section 1 description and correlation between gait impairment and hydrocephalus were made in 1965 by Hakim and Adam (\citep{B1}). 
The etiology of idiopathic normal pressure hydrocephalus (iNPH) has not yet been entirely understood (\citep{B2,B3,B4,B5}). 
In elderly patients, other conditions such as spinal canal stenosis, Parkinson's disease, and polyneuropathy may influence the gait negatively.\par

This is the full code:

\documentclass{article}
\usepackage{luacode}
\usepackage{natbib}
\begin{document}
\begin{luacode}
local domobject = require "luaxml-domobject"
local transform = require "luaxml-transform"
sample = [[
<?xml version="1.0" encoding="utf-8"?>
<art>
<title>Scattering of flexural waves an electric current</title>
<para>Smart testing structures are $a+b$ components Reduce acoustic noise used in engineering applications that are capable of sensing or reacting to their environment change <?LuaLaTeX Sample XXX1?> their mechanical properties. in a predictable and desired manner. In addition to carrying mechanical loads, <?LuaLaTeX \hspace{12pt}Abc?> alleviate vibration, reduce acoustic noise, change their mechanical properties as required or monitor their own condition.</para>
<para>The first <xref ref-type="section" rid="Sec1">Section 1</xref> description and correlation between gait impairment and hydrocephalus were made in 1965 by Hakim and Adam (<xref ref-type="bibr" rid="B1">1</xref>). The etiology of idiopathic normal pressure hydrocephalus (iNPH) has not yet been entirely understood (<xref ref-type="bibr" rid="B2">2</xref>&#x02013;<xref ref-type="bibr" rid="B5">5</xref>). In elderly patients, other conditions such as spinal canal stenosis, Parkinson&#x00027;s disease, and polyneuropathy may influence the gait negatively.</para>
</art>]]
local dom = domobject.parse(sample)
local function process_instructions(el)
  for _, child in ipairs(el:get_children()) do
    local ntype = child:get_node_type()
    if ntype == "PI" and child._name=="LuaLaTeX" then
      local text = child._attr[ "_text" ]
      local newel = el:create_element("lualatex-instruction", {text = text})
      child:replace_node(newel)
    end
    if child:is_element() then
      process_instructions(child)
    end
  end
end
-- try to find <xref> followed by dash and another <xref>
-- we then expand rid attributes
for _, xref in ipairs(dom:query_selector("xref[ref-type='bibr']")) do
  local first = xref:get_sibling_node(1)
  local second = xref:get_sibling_node(2)
  if first and second and
     first:is_text() and first:get_text() == "–" and -- next node must be "–" text
     second:is_element() and second:get_element_name() == "xref" -- second element must be <xref>
  then
    local rid1 = xref:get_attribute("rid") or ""
    local rid2 = second:get_attribute("rid") or ""
    local prefix1, number1 = rid1:match("(%a+)(%d+)")
    local prefix2, number2 = rid2:match("(%a+)(%d+)")
    -- expand only if prefixes match each other
    if prefix1 and prefix2 and prefix1 == prefix2 then
      -- expand numbers
      local t = {}
      for i = number1, number2 do
        t[#t+1] = prefix1 .. math.floor(i)
      end
      -- save expanded numbers
      xref:set_attribute("rid", table.concat(t, ","))
      -- remove unnecessary elements
      first:remove_node()
      second:remove_node()
    end
  end
end
process_instructions(dom:root_node())
local transformer = transform.new()
transformer:add_action("title", "\section{@<.>}")
transformer:add_action("para", "@<.>\par")
transformer:add_action("xref[ref-type='bibr']", "\citep{@{rid}}")
-- handle the processing instruction
transformer:add_custom_action("lualatex-instruction",
    function(el)
        return el:get_attribute("text")
    end)
local result = transformer:process_dom(dom)
print(result)
transform.print_tex(result)
\end{luacode*}
\end{document}

It's possible to do lua script in separate LaTeX Style file?. It means like to add in the LaTeX file \usepackage{bibr} and all the lua scripts in bibr.sty file only, so no need any luacode in the LaTeX file. — Balaji, Jul 26 '23 at 06:06
@Balaji of course, you would just need to make a command that accepts XML code or filename and then processes it. — michal.h21, Jul 26 '23 at 08:48
I have tried to cut the luacode from LaTeX and created bibr.sty file. But, it's showing compile error. Could you please advise how to do this. It's good to modify your answer... — Balaji, Jul 26 '23 at 10:45
I have posted new question https://tex.stackexchange.com/questions/692017/lua-script-in-separate-latex-style-file — Balaji, Jul 26 '23 at 12:00

BIBR expend as per Input XML using LuaLaTeX

1 Answers1