% \iffalse meta-comment
%
%% File: latex-lab-namespace.dtx 
%% 
% Copyright (C) 2023-2026 LaTeX Project
%
% It may be distributed and/or modified under the conditions of the
% LaTeX Project Public License (LPPL), either version 1.3c of this
% license or (at your option) any later version.  The latest version
% of this license is in the file
%
%    https://www.latex-project.org/lppl.txt
%
%<*package>
\def\ltlabnamesdate{2026-04-28}
\def\ltlabnamesversion{0.8k}
%</package>
%<*driver>
\DocumentMetadata{tagging=on,pdfstandard=ua-2}
\documentclass[kernel]{l3in2edoc}

\usepackage{amstext}
\EnableCrossrefs
\CodelineIndex

\usepackage{todonotes}

\begin{document}
  \DocInput{latex-lab-namespace.dtx}
\end{document}
%</driver>
% \fi
% \title{Prototype reimplementation of \LaTeXe{}'s role mapping}
% \author{\LaTeX{} Project, initial implementation Ulrike Fischer}
% \date{v\ltlabnamesversion\ \ltlabnamesdate}
%
% \maketitle
%
% \NewDocumentCommand\fmi{sO{}m}
%   {\IfBooleanTF{#1}{\todo[inline,#2]{#3}}^^A
%                    {\todo[#2]{#3}}}
%                    
% % \NewDocumentCommand\ufi{sO{}m}
%   {\IfBooleanTF{#1}{\todo[inline,#2]{UFi:#3}}^^A
%                    {\todo[#2]{UFi:#3}}}                   
% \begin{documentation}
%
%
%
% \section{Introduction}
%
% This file provides support for tag names and symbolic structure names.
% 
% At first, it creates tagpdf-ns-latex-lab.def which collects tag names
% from the \LaTeX{} namespace and their role mapping.
% The names and the roles are not necessarily the final ones! 
% 
% Later settings of the same tag overwrite previous settings.
% The syntax of a line is a list of three strings ending with commas:
% \begin{verbatim}
% latex-tag, PDF-tag, name space,
% \end{verbatim}
% 
% The name space is normally pdf2 with the exception of the following PDF-tags 
% which are only in pdf namespace: 
% Art, BlockQuote, TOC, TOCI, Index, Private, Quote, Note,
%  Reference, BibEntry, Code.
%  
%  At second it provides an interface to use symbolic structure names 
%  which can be used in the \texttt{tag} key of \cs{tagstructbegin}. 
%  The symbolic names are strings
%  structured with slashes similar to the names of (tagging) sockets. 
%  The list of such names used by \LaTeX{} is below in the implementation section.
%  
%  In PDF 2.0 there are namespaces, so theoretically it is possible to use the 
%  same tag name for different purposes and with different role mapping. 
%  But practically this is not an option as we build also a global RoleMap 
%  dictionary for compatibility with applications that are not PDF 2.0 aware,
%  and this dictionary can only contain unique tag names. So we assume that tag 
%  names are used only once across all namespaces. Documents that want to use 
%  their own specialized tag names must take care not to clash with existing names,
%  e.g., by using a specific prefix on all their tag names.
% 
%  \begin{function}{\NewStructureName}
%   \begin{syntax}
%    \cs{NewStructureName}\Arg{symbolic name}
%   \end{syntax}
%   This declares a new symbolic 
%   structure name \meta{symbolic name} which is initially 
%   defined as \texttt{NonStruct}. To assign it another role use 
%   \cs{AssignStructureRole} described below.
%  \end{function}
%  
%  \begin{function}[EXP]{\UseStructureName}
%   \begin{syntax}
%    \cs{UseStructureName}\Arg{symbolic name}
%   \end{syntax}
%   This uses the new symbolic structure name \meta{symbolic name}, e.g.\\
%   \verb+tagstructbegin{tag=\UseStructureName{sec/section}}+ is the same as
%   \verb+tagstructbegin{tag=Sect}+ assuming that 
%   \verb+\NewStructureName{sec/section}+ and \verb+\AssignStructureRole{sec/section}{Sect}+
%   has been used before.
%  \end{function}
%  
%  \begin{function}{\AssignStructureRole}
%   \begin{syntax}
%    \cs{AssignStructureRole}\Arg{symbolic name}\Arg{role}
%   \end{syntax}
%   This assigns to the symbolic structure name \meta{symbolic name} the role \meta{role}. 
%   \meta{symbolic name} must have been declared first with \verb+\NewStructureName+. 
%   If \meta{role} is a known role it is simply used. If it is unknown, it is declared
%   first and rolemapped to the tag currently stored for \meta{name}. So 
%   \begin{verbatim}
%   \NewStructureName{sec/section}
%   % structure with tag 'NonStruct'
%   \tagstructbegin{tag=\UseStructureName{sec/section}}
%      
%   \AssignStructureRole{sec/section}{Sect}
%   % structure with tag 'Sect'
%   \tagstructbegin{tag=\UseStructureName{sec/section}}
%   
%   \AssignStructureRole{sec/section}{Abschnitt}
%   % structure with tag 'Abschnitt' rolemapped to 'Sect'
%   \tagstructbegin{tag=\UseStructureName{sec/section}}
%   
%   \AssignStructureRole{sec/section}{Figure}
%   % structure with tag 'Figure' 
%   \tagstructbegin{tag=\UseStructureName{sec/section}}
%   \end{verbatim}
%   
%   Assigning a symbolic structure name a role that is not suitable for the 
%   structure element can lead to invalid tagging and parent-child warnings! 
%  \end{function}
% \end{documentation}
% 
% \begin{implementation}
% \changes{v0.8c}{2025/01/12}{changed mapping of verbatim to Code as Sub is now allowed inside Code}
%    \begin{macrocode}
%<*ns-latex-lab>
%% \ProvidesExplFile {tagpdf-ns-latex-lab.def} {2023-09-04} {0.8}
%% {latex} {https://www.latex-project.org/ns/lab/2022}{}
%    \end{macrocode}
% \subsection{Role from tagpdf}
% The following tags are already set by tagpdf, so deleting here will not remove them.
%    \begin{macrocode}
title,        Title,    pdf2,
part,         Title,    pdf2,
%    \end{macrocode}
%    Headings differ in article and book class. This here is for article:
%    \begin{macrocode}
section,      H1,       pdf2, 
subsection,   H2,       pdf2,
subsubsection,H3,       pdf2,
paragraph,    H4,       pdf2, 
subparagraph, H5,       pdf2,
%    \end{macrocode}
%    And this here is used in book:
%    \begin{macrocode}
%chapter,       H1,      pdf2,
%section,       H2,      pdf2,
%subsection,    H3,      pdf2,
%subsubsection, H4,      pdf2,
%paragraph,     H5,      pdf2,
%subparagraph,  H6,      pdf2,
%    \end{macrocode}
%
%    \begin{macrocode}
list,         L,        pdf2,
itemize,      L,        pdf2,
enumerate,    L,        pdf2,
description,  L,        pdf2,
quote,        BlockQuote,pdf,
quotation,    BlockQuote,pdf,
verbatim,     Code,     pdf,  % overwritten by block
item,         LI,       pdf2,
itemlabel,    Lbl,      pdf2,
itembody,     LBody,    pdf2,
footnote,     FENote,   pdf2,
footnotemark, Lbl,      pdf2,
footnotelabel,Lbl,      pdf2,
text-unit,    Part,     pdf2,
text,         P,        pdf2,
%    \end{macrocode}
% \subsection{From sec code}
%    \begin{macrocode}
section-number, Span,     pdf2,
%    \end{macrocode}
% \subsection{From block code}
%    \begin{macrocode}
theorem-like, Sect,     pdf2,
verbatim,     Code,     pdf,
codeline,     Sub,      pdf2,
%    \end{macrocode}
% \subsection{From float code}
%    \begin{macrocode}
float,        Aside,    pdf2,
figures,      Sect,     pdf2,
tables,       Sect,     pdf2,
%    \end{macrocode}
%    \begin{macrocode}
%</ns-latex-lab>
%    \end{macrocode}
%
%    \begin{macrocode}
%<*package>
\ProvidesExplPackage {latex-lab-testphase-names} {\ltlabnamesdate} {\ltlabnamesversion}
  {Code related to the names of tags}
%    \end{macrocode}
%    \begin{macrocode}
%<@@=tag>
%    \end{macrocode}
%
% 
% \begin{macro}{\AssignStructureRole}
%    We redefine \cs{AssignStructureRole} to set up roles for tagging.
%    The second argument needs expansion so that we do
%    not store things like
%    \verb=\UseStructureName{block/verbatim/codeline}}= but its final
%    value. Otherwise \ldots\fmi{fix implementation and docu}
% \changes{v0.8h}{2025/12/23}{Expand second argument before storing}
%    \begin{macrocode}
\cs_set_protected:Npn\AssignStructureRole#1#2 {
  \exp_args:Nne \@@_AssignStructureRole {#1}{#2}
}    
\cs_set_protected:Npn\@@_AssignStructureRole#1#2
 {
   \prop_get:NnNF\g_@@_role_tags_NS_prop{#2}\l_@@_tmp_unused_tl
    {\exp_args:Ne\tagpdfsetup{role/new-tag=#2/\UseStructureName{#1}}}
   \tl_set:cn { l_@@_name_#1_tl }{#2}
 }
%    \end{macrocode}
% \end{macro}
% 
% 
%    \begin{macrocode}
%</package>
%    \end{macrocode}
% 
% \subsection{Symbolic names}
% These are the planned symbolic structure names. 
% Every commented name is not decided and not used yet and can change in future. 
% 
% \subsubsection{Generic}
% In various places we have to use a \texttt{Span} structure
% to add attributes.
%    \begin{macrocode}
%<*package>
\NewStructureName{span}
\AssignStructureRole{span}{Span}
%</package>
%    \end{macrocode}
%
% \subsubsection{Paragraphs}
% 
%    \begin{macrocode}
%<*package>
\NewStructureName{para/textblock}
\AssignStructureRole{para/textblock}{text}
\NewStructureName{para/semantic}
\AssignStructureRole{para/semantic}{text-unit}
%</package>
%    \end{macrocode}
% 
% \subsubsection{Sectioning commands}
%    \begin{macrocode}
%<*package>
%-1=part, 0=chapter, 1=section etc
\NewStructureName{sec/-1}
\AssignStructureRole{sec/-1}{Part}
\NewStructureName{sec/-1/title}
\AssignStructureRole{sec/-1/title}{part}
\NewStructureName{sec/-1/titleline}
%    \end{macrocode}
% Sub does not work as part is rolemapped to Title so we use Span 
%    \begin{macrocode}
\AssignStructureRole{sec/-1/titleline}{Span} 
\NewStructureName{sec/-1/number}
\AssignStructureRole{sec/-1/number}{section-number}
\NewStructureName{sec/0}
\AssignStructureRole{sec/0}{Sect}
\NewStructureName{sec/0/title}
\AssignStructureRole{sec/0/title}{chapter}
\NewStructureName{sec/0/titleline}
\AssignStructureRole{sec/0/titleline}{Span}
\NewStructureName{sec/0/number}
\AssignStructureRole{sec/0/number}{section-number}
\NewStructureName{sec/1}
\AssignStructureRole{sec/1}{Sect}
\NewStructureName{sec/1/title}
\AssignStructureRole{sec/1/title}{section}
\NewStructureName{sec/1/number}
\AssignStructureRole{sec/1/number}{section-number}
\NewStructureName{sec/2}
\AssignStructureRole{sec/2}{Sect}
\NewStructureName{sec/2/title}
\AssignStructureRole{sec/2/title}{subsection}
\NewStructureName{sec/2/number}
\AssignStructureRole{sec/2/number}{section-number}
\NewStructureName{sec/3}
\AssignStructureRole{sec/3}{Sect}
\NewStructureName{sec/3/title}
\AssignStructureRole{sec/3/title}{subsubsection}
\NewStructureName{sec/3/number}
\AssignStructureRole{sec/3/number}{section-number}
\NewStructureName{sec/4}
\AssignStructureRole{sec/4}{Sect}
\NewStructureName{sec/4/title}
\AssignStructureRole{sec/4/title}{paragraph}
\NewStructureName{sec/4/number}
\AssignStructureRole{sec/4/number}{section-number}
\NewStructureName{sec/5}
\AssignStructureRole{sec/5}{Sect}
\NewStructureName{sec/5/title}
\AssignStructureRole{sec/5/title}{subparagraph}
\NewStructureName{sec/5/number}
\AssignStructureRole{sec/5/number}{section-number}
%    \end{macrocode}
%
% \subsubsection{Table of contents and similar} 
%    \begin{macrocode}
\NewStructureName{toc}
\AssignStructureRole{toc}{TOC}
\NewStructureName{toc/item}
\AssignStructureRole{toc/item}{TOCI}
\NewStructureName{toc/item/label}
\AssignStructureRole{toc/item/label}{Lbl}
\NewStructureName{toc/item/text}
\AssignStructureRole{toc/item/text}{Reference}
\NewStructureName{toc/item/page}
\AssignStructureRole{toc/item/page}{Reference}
%    \end{macrocode}
%
% \subsubsection{Title}
% \enquote{title} in this context can be a structure that surrounds the \emph{title block} (or a part from it)
% with author, title, subtitle, date and perhaps more. Or it can mean only the \emph{title text} (plus perhaps
% the subtitle). 
% In PDF 2.0 the tag \texttt{Title} is described as grouping and block type and it can not be used
% in a \texttt{P} tag, so it is better used for the \emph{title block}.
% With PDF 1.7 \texttt{Title} is currently rolemapped to \texttt{P} and
% the code in latex-lab-title uses it for the \emph{title text}. 
% \ufi{This should be discussed.}
% We provide therefore two symbolic names for the two concepts, which both map to \texttt{Title}.
%    \begin{macrocode}
\NewStructureName{title/block}
\AssignStructureRole{title/block}{Title}  
\NewStructureName{title/text}
\AssignStructureRole{title/text}{Title} 
%    \end{macrocode}
%
% \subsubsection{Lists and blocks}
% \texttt{block/inner} is the generic named used for inner blocks  
% in, e.g., the recipe \texttt{standard}.
%    \begin{macrocode}
\NewStructureName{block/inner}
\AssignStructureRole{block/inner}{Div} 
\NewStructureName{block/itemize}
\AssignStructureRole{block/itemize}{itemize}
\NewStructureName{block/description}
\AssignStructureRole{block/description}{description}        
\NewStructureName{block/enumerate}
\AssignStructureRole{block/enumerate}{enumerate}        
\NewStructureName{block/list}
\AssignStructureRole{block/list}{list}        
\NewStructureName{block/list/item}
\AssignStructureRole{block/list/item}{item}   
\NewStructureName{block/list/label}
\AssignStructureRole{block/list/label}{itemlabel}  
\NewStructureName{block/list/body}
\AssignStructureRole{block/list/body}{itembody} 
%    \end{macrocode}
%    
%    \begin{macrocode}
\NewStructureName{block/quote}
\AssignStructureRole{block/quote}{quote}
%    \end{macrocode}
%    
%    For now we map \texttt{verse} to \texttt{quote} which means
%    it will become BlockQuote in tagging.\fmi{decide on tagging
%    for verse}
%    \begin{macrocode}
\NewStructureName{block/verse}
\AssignStructureRole{block/verse}{quote}
%    \end{macrocode}
%    
%    \begin{macrocode}
\NewStructureName{block/quotation}
\AssignStructureRole{block/quotation}{quotation}
%
\NewStructureName{block/verbatim}
\AssignStructureRole{block/verbatim}{verbatim}
\NewStructureName{block/verbatim/codeline}
\AssignStructureRole{block/verbatim/codeline}{codeline}
\NewStructureName{block/verbatim/linenumber}
\AssignStructureRole{block/verbatim/linenumber}{Lbl}
%
\NewStructureName{block/theorem-like}
\AssignStructureRole{block/theorem-like}{theorem-like}
\NewStructureName{block/theorem-like/caption}
\AssignStructureRole{block/theorem-like/caption}{Caption}   
\NewStructureName{block/theorem-like/label}
\AssignStructureRole{block/theorem-like/label}{Lbl}
%    \end{macrocode}
%    For now we map proof to theorem-like:
%    \begin{macrocode}
\NewStructureName{block/proof}
\AssignStructureRole{block/proof}{theorem-like}
%    \end{macrocode}
%    
% Bibliographies normally use internally lists and tag names should be adapted
% by changing the symbolic names of lists locally, so dedicated symbolic names
% are probably not needed.   
%    \begin{macrocode}
%\NewStructureName{block/bib}
%\AssignStructureRole{block/bib}{L}
%\NewStructureName{block/bib/label}
%\AssignStructureRole{block/bib/label}{Lbl}
%\NewStructureName{block/bib/item}
%\AssignStructureRole{block/bib/item}{LI}
%\NewStructureName{block/bib/body}
%\AssignStructureRole{block/bib/body}{LBody} 
%    \end{macrocode}
%
%\subsubsection{\LaTeX{} Code documentation}
% The class l3doc defines a number of structures for the document of \LaTeX\ code.
% The exact tagging is currently experimental and it is unclear if 
% symbolic names and tag names for this case should be setup here by default.
% Their setup is therefore done in latex-lab-l3doc-tagging.
% 
% 
%\subsubsection{References and Links}
% 
%    \begin{macrocode}
\NewStructureName{ref}
\AssignStructureRole{ref}{Reference}
\NewStructureName{link}
\AssignStructureRole{link}{Link}
\NewStructureName{cite}
\AssignStructureRole{cite}{Reference}
%    \end{macrocode}
%
% \subsubsection{Tables}
% 
%    \begin{macrocode}
\NewStructureName{table}
\AssignStructureRole{table}{Table}
\NewStructureName{table/row}
\AssignStructureRole{table/row}{TR}
\NewStructureName{table/cell}
\AssignStructureRole{table/cell}{TD}
\NewStructureName{table/headercell}
\AssignStructureRole{table/headercell}{TH}
%    \end{macrocode}
% THead and TFoot are currently not used but are perhaps needed later
%    \begin{macrocode}
%\NewStructureName{tbl/table/head}
%\AssignStructureRole{tbl/table/head}{}
%\NewStructureName{tbl/table/foot}
%\AssignStructureRole{tbl/table/foot}{}
%    \end{macrocode}
% Inside p-cells we have to set the para/semantic structure to Div as Part is not
% allowed as child of TD and as we can not flatten the paragraphs.
%    \begin{macrocode}
\NewStructureName{table/para/semantic}
\AssignStructureRole{table/para/semantic}{Div}
%    \end{macrocode}
% We need also names for layout tables
%    \begin{macrocode}
\NewStructureName{layouttable}
\AssignStructureRole{layouttable}{Div}
\NewStructureName{layouttable/row}
\AssignStructureRole{layouttable/row}{NonStruct}
\NewStructureName{layouttable/cell}
\AssignStructureRole{layouttable/cell}{\UseStructureName{para/textblock}}
\NewStructureName{layouttable/pcell}
\AssignStructureRole{layouttable/pcell}{NonStruct}
%    \end{macrocode}
%
% 
%
% \subsubsection{Floats}
% 
%    \begin{macrocode}
\NewStructureName{float/generic}
\AssignStructureRole{float/generic}{float}
\NewStructureName{float/figures}
\AssignStructureRole{float/figures}{figures}
\NewStructureName{float/tables}
\AssignStructureRole{float/tables}{tables}
\NewStructureName{float/figure}
\AssignStructureRole{float/figure}{float}
\NewStructureName{float/table}
\AssignStructureRole{float/table}{float}
\NewStructureName{float/figure/caption}
\AssignStructureRole{float/figure/caption}{Caption} 
\NewStructureName{float/table/caption}
\AssignStructureRole{float/table/caption}{Caption}  
\NewStructureName{float/figure/label}
\AssignStructureRole{float/figure/label}{Lbl}
\NewStructureName{float/table/label}
\AssignStructureRole{float/table/label}{Lbl}
%    \end{macrocode}
%
% \subsubsection{Footnotes}
% 
%    \begin{macrocode}
\NewStructureName{fnote/mark}
\AssignStructureRole{fnote/mark}{footnotemark}
\NewStructureName{fnote/note}
\AssignStructureRole{fnote/note}{footnote}
\NewStructureName{fnote/note/label}
\AssignStructureRole{fnote/note/label}{footnotelabel}
%    \end{macrocode}
%
% \subsubsection{Graphics}
%    \begin{macrocode}
\NewStructureName{graphic}
\AssignStructureRole{graphic}{Figure}
\NewStructureName{graphic/symbol}
\AssignStructureRole{graphic/symbol}{Span}
%    \end{macrocode}
%
% \subsubsection{Marginnotes}
%    \begin{macrocode}
\NewStructureName{marginnote}
\AssignStructureRole{marginnote}{Aside}
%    \end{macrocode}
%
% \subsubsection{Minipages and parboxes}
%    \begin{macrocode}
\NewStructureName{minipage}
\AssignStructureRole{minipage}{Div}
\NewStructureName{parbox}
\AssignStructureRole{parbox}{Div}
%    \end{macrocode}
%
% \subsubsection{Text}
%    \begin{macrocode}
\NewStructureName{text/emph}
\AssignStructureRole{text/emph}{Em}
\NewStructureName{text/verb}
\AssignStructureRole{text/verb}{Code}
%    \end{macrocode}
%
% \subsubsection{Math}
% Math uses internally MathML and this should not be remapped so we need only
% names for the outer \texttt{Formula} tag and perhaps for a label:
%    \begin{macrocode}
\NewStructureName{math/inline}
\AssignStructureRole{math/inline}{Formula}
\NewStructureName{math/display}
\AssignStructureRole{math/display}{Formula}
\NewStructureName{math/label}
\AssignStructureRole{math/label}{Lbl}
%    \end{macrocode}
%
% \subsubsection{Index and glossaries}
% Tagging not decided yet.
% 
% \subsection{Attributes}
% \changes{v0.8j}{2026-04-27}{Add kernel attributes}
% \changes{v0.8k}{2026-04-28}{Add more kernel attributes}
% The latex-lab code sets up a number of kernel attributes. These are collected here:
%    \begin{macrocode}
\tagpdfsetup
 {
%    \end{macrocode}
% \subsection{Text attributes}
% These attributes are for super- and subscripts and are used in latex-lab-text:
%    \begin{macrocode}
   role/new-attribute = {sub} {/O /Layout /TextPosition/Sub},
   role/new-attribute = {sup} {/O /Layout /TextPosition/Sup},
%    \end{macrocode}
% These are for text alignment and they are used in latex-lab-block:
   role/new-attribute = {justify}    {/O /Layout /TextAlign/Justify},
   role/new-attribute = {center}     {/O /Layout /TextAlign/Center},
   role/new-attribute = {raggedright}{/O /Layout /TextAlign/Start},
   role/new-attribute = {raggedleft} {/O /Layout /TextAlign/End},    
% \subsection{Math attributes}
%    \begin{macrocode}
   role/new-attribute = {inline}  {/O /Layout /Placement/Inline},
   role/new-attribute = {display} {/O /Layout /Placement/Block},
%    \end{macrocode}
% \subsection{List attributes}
%    \begin{macrocode}
   role/new-attribute = {itemize}
                         {/O /List /ListNumbering/Unordered},
   role/new-attribute = {enumerate}
                         {/O /List /ListNumbering/Ordered},       
   role/new-attribute = {description}
                         {/O /List /ListNumbering/Description},
%    \end{macrocode}
%    Initially, we had \texttt{/None} for the basic \env{list}
%    environment, but that is not allowed in PDF/UA-2 if the list
%    contains any Lbl tags. So the \texttt{list} attribute uses 
%    \texttt{Unordered} too.
%    \begin{macrocode}
   role/new-attribute = {list}{/O /List /ListNumbering/Unordered},
%    \end{macrocode}
% \subsection{Table attributes}
% The code predeclares three attribute names for the scope of header,
% \texttt{TH-col}, \texttt{TH-row}, \texttt{TH-both}.
% The latex-lab-table code declares on the fly additional attributes 
% \texttt{colspan-\meta{number}} and \texttt{rowspan-\meta{number}}
% with the content \texttt{/O /Table /ColSpan \meta{number}} and
% \texttt{/O /Table /RowSpan \meta{number}}
%    \begin{macrocode}
   role/new-attribute = {TH-col}  {/O /Table /Scope /Column},
   role/new-attribute = {TH-row}  {/O /Table /Scope /Row},
   role/new-attribute = {TH-both} {/O /Table /Scope /Both},
   role/new-attribute = {ARIA-role-presentation} 
                          {/O /ARIA-1.1/role (presentation)}
%    \end{macrocode}
%    \begin{macrocode}
  } %end tagpdfsetup
%    \end{macrocode}
% The three main table attributes are put directly into the class map 
% TODO: either tagpdf should do that directly all roles or offer an interface:
%    \begin{macrocode}
\ExplSyntaxOn
    \seq_gput_left:Ne\g__tag_attr_class_used_seq
      {\pdf_name_from_unicode_e:n{TH-col}}
    \seq_gput_left:Ne\g__tag_attr_class_used_seq
      {\pdf_name_from_unicode_e:n{TH-row}}
    \seq_gput_left:Ne\g__tag_attr_class_used_seq
      {\pdf_name_from_unicode_e:n{TH-both}}
\ExplSyntaxOff      
%    \end{macrocode}
%    \begin{macrocode}
%</package>  
%    \end{macrocode}
% \end{implementation}
\endinput