% \iffalse meta-comment
%
% File: expkv-opt.dtx Copyright (C) 2020 Jonathan P. Spratte
%
% This work  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:
%
%   http://www.latex-project.org/lppl.txt
%
% ------------------------------------------------------------------------------
%
%<*driver>^^A>>=
\def\nameofplainTeX{plain}
\ifx\fmtname\nameofplainTeX\else
  \expandafter\begingroup
\fi
\input l3docstrip.tex
\askforoverwritefalse
\preamble

--------------------------------------------------------------
expkv-opt -- parse class and package options with expkv
E-mail: jspratte@yahoo.de
Released under the LaTeX Project Public License v1.3c or later
See http://www.latex-project.org/lppl.txt
--------------------------------------------------------------

Copyright (C) 2020 Jonathan P. Spratte

This  work 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:

  http://www.latex-project.org/lppl.txt

This work is "maintained" (as per LPPL maintenance status) by
  Jonathan P. Spratte.

This work consists of the file  expkv-opt.dtx
and the derived files           expkv-opt.pdf
                                expkv-opt.sty

\endpreamble
% stop docstrip adding \endinput
\postamble
\endpostamble
\generate{\file{expkv-opt.sty}{\from{expkv-opt.dtx}{pkg}}}
\ifx\fmtname\nameofplainTeX
  \expandafter\endbatchfile
\else
  \expandafter\endgroup
\fi
%
\IfFileExists{expkv-opt.sty}{\RequirePackage{expkv-opt}}{}
\ProvidesFile{expkv-opt.dtx}
  [\csname ekvoDate\endcsname\ parse class and package options with expkv]
\PassOptionsToPackage{full}{textcomp}
\documentclass{l3doc}
\RequirePackage[oldstylenums,nott]{kpfonts}
\input{glyphtounicode}
\pdfgentounicode=1
\RequirePackage{listings}
\RequirePackage{booktabs}
\RequirePackage{array}
\RequirePackage{collcell}
\RequirePackage{siunitx}
\RequirePackage{xcolor}
\RequirePackage{caption}
\RequirePackage{microtype}
\RequirePackage{accsupp}
\lstset
  {
    ,flexiblecolumns=false
    ,basewidth=.53em
    ,gobble=2
    ,basicstyle=\fontfamily{jkp}\itshape
    ,morekeywords=^^A
      {^^A
        \ekvoProcessLocalOptions,
        \ekvoProcessGlobalOptions,
        \ekvoProcessUnusedGlobalOptions,
        \ekvoProcessOptionsList,
        \ekvoUseUnknownHandlers
      }
    ,morecomment=[l]\%
    ,commentstyle=\color[gray]{0.4}
    ,literate={\{}{{\CodeSymbol\{}}{1}
              {\}}{{\CodeSymbol\}}}{1}
    ^^A,literate=*{<key>}{\key}{4}{<set>}{\set}{4}
  }
\newcommand*\CodeSymbol[1]{\textbf{#1}}
\RequirePackage{randtext}
\let\metaORIG\meta
\protected\def\meta #1{\texttt{\metaORIG{#1}}}
\renewcommand*\thefootnote{\fnsymbol{footnote}}
\definecolor{expkvred}{HTML}{9F393D}
\colorlet{expkvgrey}{black!75}
\makeatletter
\newcommand*\expkv
  {^^A
    \texorpdfstring
      {^^A
        \mbox
          {^^A
            \BeginAccSupp{ActualText=expkv}^^A
            \href{https://github.com/Skillmon/tex_expkv}
              {^^A
                \rmfamily
                \bfseries
                {\color{expkvgrey}e\kern-.05em x\kern-.05em}^^A
                \lower.493ex
                  \hbox{{\color{expkvgrey}P}\kern-.1em{\color{expkvred}k}}^^A
                \kern-.18em{\color{expkvred}v}^^A
              }^^A
            \EndAccSupp{}^^A
          }^^A
      }
      {expkv}^^A
  }
\newcommand*\expkvpkg[1]
  {^^A
    \texorpdfstring
      {^^A
        \mbox
          {^^A
            \BeginAccSupp{ActualText=expkv-#1}^^A
            \href{https://github.com/Skillmon/tex_expkv-#1}
              {^^A
                \rmfamily
                \bfseries
                {\color{expkvgrey}e\kern-.05em x\kern-.05em}^^A
                \lower.493ex
                  \hbox{{\color{expkvgrey}P}\kern-.1em{\color{expkvred}k}}^^A
                \kern-.18em{\color{expkvred}v}^^A
                {\color{expkvgrey}^^A
                  \kern.05em\rule[-.1ex]{.08em}{1.2ex}\kern.05em\textsc{#1}^^A
                }^^A
              }^^A
            \EndAccSupp{}^^A
          }^^A
      }
      {expkv-#1}^^A
  }
\newcommand*\expkvd{\expkvpkg{def}}
\newcommand*\expkvc{\expkvpkg{cs}}
\newcommand*\expkvo{\expkvpkg{opt}}
\newcommand\kv{\meta{key}=\meta{value}}
\newcommand\key{\meta{key}}
\newcommand\val{\meta{value}}
\newcommand\set{\meta{set}}
\hypersetup{linkcolor=red!80!black,urlcolor=purple!80!black}
\DoNotIndex{\def,\edef,\,,\=,\begingroup,\catcode,\chardef,\csname,\endcsname}
\DoNotIndex{\endgroup,\endinput,\errmessage,\expandafter,\input,\let,\long}
\DoNotIndex{\protected,\ProvidesFile,\ProvidesPackage,\relax,\space}
\DoNotIndex{\@,\unexpanded,\string,\expanded,\dimexpr,\global,\glueexpr,\hbox}
\DoNotIndex{\numexpr,\RequirePackage,\setbox,\the,\unless,\xdef,\@firstofone}
\DoNotIndex{\@firstoftwo,\@gobble,\@secondoftwo,\AtEndOfPackage,\newcommand}
\DoNotIndex{\PackageError,\@classoptionslist,\@clsextension,\@currext}
\DoNotIndex{\@currname,\@empty,\@gobbletwo,\@onlypreamble,\@raw@classoptionslist}
\DoNotIndex{\@unprocessedoptions,\@unusedoptionlist}
\DoNotIndex{\DeclareRelease,\DeclareCurrentRelease,\IfFormatAtLeastTF}
\DoNotIndex{\PackageWarning,\requestedLaTeXdate,\@ifstar}
\DoNotIndex{\pkgcls@parse@date@arg,\pkgcls@targetdate,\pkgcls@targetlabel}
\DoNotIndex{\ifcsname}
\DoNotIndex{\ifx}
\DoNotIndex{\ifdefined}
\DoNotIndex{\iffalse}
\DoNotIndex{\iftrue}
\DoNotIndex{\ifnum}
\DoNotIndex{\else}
\DoNotIndex{\fi}
\@gobble\fi ^^A ignoring \ifx, \ifcsname, etc., but only one \fi
\@gobble\fi ^^A ignoring \ifx, \ifcsname, etc., but only one \fi
\@gobble\fi ^^A ignoring \ifx, \ifcsname, etc., but only one \fi
\@gobble\fi ^^A ignoring \ifx, \ifcsname, etc., but only one \fi
\@gobble\fi ^^A ignoring \ifx, \ifcsname, etc., but only one \fi
\@ifdefinable\gobbledocstriptag{\def\gobbledocstriptag#1>{}}
\makeatother
\begin{document}
  \title
    {^^A
      \texorpdfstring
        {^^A
          \huge\expkvo
          \\[\medskipamount]
          \Large parse class and package options with \expkv
        }{expkv-opt - parse class and package options with expkv}^^A
    }
  \date{\ekvoDate\space v\ekvoVersion}
  \author{Jonathan P. Spratte\thanks{\protect\randomize{jspratte@yahoo.de}}}
  \DocInput{expkv-opt.dtx}
\end{document}
%</driver>^^A=<<
% \fi
%
% \maketitle
% \renewcommand*\thefootnote{\arabic{footnote}}
%
% \begin{abstract}
% \noindent\parfillskip=0pt
% \expkvo\ provides option parsing for classes and packages in \LaTeXe\ based on
% \expkv. Global and local options are parsed individually by different
% commands. The stylised name is \expkvo\ but the files use \file{expkv-opt},
% this is due to CTAN-rules which don't allow \string| in package names since
% that is the pipe symbol in *nix shells.
% \end{abstract}
%
% \tableofcontents
%
% \begin{documentation}^^A>>=
%
% \section{Documentation}
%
% The \expkv\ family provides at its core a \kv\ parser and additionally
% packages, one to conveniently define new keys (\expkvd) and another to build
% expandable \kv\ taking control sequences (\expkvc). Still missing from the mix
% was a solution to parse \LaTeXe\ class and package options, a gap that's
% hereby filled with \expkvo.
%
% With the 2021-05-01 release of \LaTeXe\ there were some very interesting
% changes to the package and class options code. It is now possible to use
% braces inside the options, and we can access options without them being
% preprocessed. As a result, some but not all restrictions were lifted from the
% possible option usage. What will still fail is things that aren't save from an
% |\edef| expansion. One thing that doesn't work any more is the possibility to
% parse the unused option list, because that one doesn't contain the full
% information any more.
%
% \expkvo\ will fall back to v0.1 if the kernel is older than 2021-05-01.
% \expkvo\ shouldn't place any restrictions on the keys, historic shortcomings
% of the kernel cannot be helped though, so the supported things vary with the
% kernel version. The one thing that \expkvo\ doesn't support, which \expkv\
% alone would, is active commas. But there is no good reason why a comma could
% be active in the preamble.
%
% The package can be loaded with
% \begin{lstlisting}
% \usepackage{expkv-opt}
% \end{lstlisting}
% and if you need a specific version you can use \LaTeXe's rollback support, so
% to load v0.1 explicitly use:
% \begin{lstlisting}
% \usepackage{expkv-opt}[=v0.1]
% \end{lstlisting}
% which will load the latest subversion of v0.1
% (this shouldn't be done by a package author, but only by a user on a
% single-document basis if there are some incompatibilities, which is unlikely)
% Unlike the other packages in the \expkv\ family, \expkvo\ is only provided as
% a \LaTeX\ package.
%
% Before reading this documentation you should read \expkv's documentation and
% might want to also read the documentation of \expkvd.
%
%
% \subsection{Macros}
%
% \expkvo's behaviour if it encounters a defined or an undefined \key\ depends
% on which list is being parsed and whether the current file is a class or not.
% Of course in every case a defined \key's callback will be invoked but an
% additional action might be executed. For this reason the rule set of every
% macro will be given below the short description which list it will parse. 
%
% During each of the processing macros the current list element (not processed
% in any way) is stored within the macro \cs{CurrentOption}.
%
% \begin{function}{\ekvoProcessLocalOptions}
%   \begin{syntax}
%     \cs{ekvoProcessLocalOptions}\marg{set}
%   \end{syntax}
%   This parses the options which are directly passed to the current class or
%   package for an \expkv\ \set.
% \end{function}
% \begin{description}
%   \item[Class:]
%     \begin{description}
%       \item[defined] \emph{nothing}
%       \item[undefined]
%         add the key to the list of unused global options (if the local option
%         list matches the option list of the main class)
%     \end{description}
%   \item[Package:]
%     \begin{description}
%       \item[defined] \emph{nothing}
%       \item[undefined] throw an error
%     \end{description}
% \end{description}
%
% \begin{function}{\ekvoProcessGlobalOptions}
%   \begin{syntax}
%     \cs{ekvoProcessGlobalOptions}\marg{set}
%   \end{syntax}
%   In \LaTeXe\ the options given to |\documentclass| are global options. This
%   macro processes the global options for an \expkv\ \set.
% \end{function}
% \begin{description}
%   \item[Class:]
%     \begin{description}
%       \item[defined] remove the option from the list of unused global options
%       \item[undefined] \emph{nothing}
%     \end{description}
%   \item[Package:]
%     \begin{description}
%       \item[defined] remove the option from the list of unused global options
%       \item[undefined] \emph{nothing}
%     \end{description}
% \end{description}
%
% \begin{function}{\ekvoProcessUnusedGlobalOptions}
%   \begin{syntax}
%     \cs{ekvoProcessUnusedGlobalOptions}\marg{set}
%   \end{syntax}
%   This does no longer work with \LaTeXe\ kernels starting from 2021-05-01,
%   since the handling of the unused option list changed and no longer includes
%   the values. As a result this will throw a warning and else will be ignored.
% \end{function}
%
% \begin{function}{\ekvoProcessOptionsList}
%   \begin{syntax}
%     \cs{ekvoProcessOptionsList}\meta{list}\marg{set}
%   \end{syntax}
%   Process the \kv\ list stored in the macro \meta{list}.
% \end{function}
% \begin{description}
%   \item[Class:]
%     \begin{description}
%       \item[defined] \emph{nothing}
%       \item[undefined] \emph{nothing}
%     \end{description}
%   \item[Package:]
%     \begin{description}
%       \item[defined] \emph{nothing}
%       \item[undefined] \emph{nothing}
%     \end{description}
% \end{description}
%
% \begin{function}{\ekvoUseUnknownHandlers}
%   \begin{syntax}
%     \cs{ekvoUseUnknownHandlers}\meta{cs_1}\meta{cs_2}\quad{\normalfont\itshape or}
%     \cs{ekvoUseUnknownHandlers}*
%   \end{syntax}
%   With this macro you can change the action \expkvo\ executes if it encounters
%   an undefined \key\ for the next (and only the next) list processing macro.
%   The macro \meta{cs_1} will be called if an undefined \key\ without a \val\
%   is encountered and get one argument, being the \key. Analogous the macro
%   \meta{cs_2} will be called if an undefined \key\ with a \val\ was specified.
%   It will get two arguments, the first being the \key\ and the second the
%   \val.\par
%   If you use the starred variant, it'll not take further arguments. In this
%   case the undefined handlers defined via |\ekvdefunknown| and
%   |\ekvdefunknownNoVal| in the parsing set get used, and if those aren't
%   available they'll simply do nothing.
% \end{function}
%
% \begin{function}{\ekvoVersion,\ekvoDate}
%   These two macros store the version and date of the package.
% \end{function}
%
%
% \subsection{Example}
%
% Let's say we want to create a package that changes the way footnotes are
% displayed in \LaTeX. For this it will essentially just redefine
% \cs[no-index]{thefootnote} and we'll call this package \pkg{ex-footnote}.
% First we report back which package we are:
% \begin{lstlisting}
% \ProvidesPackage{ex-footnote}[2020-02-02 v1 change footnotes]
% \end{lstlisting}
% Next we'll need to provide the options we want the package to have.
% \begin{lstlisting}
% \RequirePackage{color}
% \RequirePackage{expkv-opt} % also loads expkv
% \ekvdef{ex-footnote}{color}{\def\exfn@color{#1}}
% \ekvdef{ex-footnote}{format}{\def\exfn@format{#1}}
% \end{lstlisting}
% We can provide initial values just by defining the two macros storing the
% value.
% \begin{lstlisting}
% \newcommand*\exfn@color{}
% \newcommand*\exfn@format{arabic}
% \end{lstlisting}
% Next we need to process the options given to the package. The package should
% only obey options directly passed to it, so we're only using
% |\ekvoProcessLocalOptions|:
% \begin{lstlisting}
% \ekvoProcessLocalOptions{ex-footnote}
% \end{lstlisting}
% Now everything that's still missing is actually changing the way footnotes
% appear:
% \begin{lstlisting}
% \renewcommand*\thefootnote
%   {%
%     \ifx\exfn@color\@empty
%       \csname\exfn@format\endcsname{footnote}%
%     \else
%       \textcolor{\exfn@color}{\csname\exfn@format\endcsname{footnote}}%
%     \fi
%   }
% \end{lstlisting}
% \bigskip
%
% \noindent
% So the complete code of the package would look like this:
% \begin{lstlisting}
% \ProvidesPackage{ex-footnote}[2020-02-02 v1 change footnotes]
%
% \RequirePackage{color}
% \RequirePackage{expkv-opt} % also loads expkv
%
% \ekvdef{ex-footnote}{color}{\def\exfn@color{#1}}
% \ekvdef{ex-footnote}{format}{\def\exfn@format{#1}}
% \newcommand*\exfn@color{}
% \newcommand*\exfn@format{arabic}
%
% \ekvoProcessLocalOptions{ex-footnote}
%
% \renewcommand*\thefootnote
%   {%
%     \ifx\exfn@color\@empty
%       \csname\exfn@format\endcsname{footnote}%
%     \else
%       \textcolor{\exfn@color}{\csname\exfn@format\endcsname{footnote}}%
%     \fi
%   }
% \end{lstlisting}
% \bigskip
%
% \noindent
% And it could be used with one of the following lines:
% \begin{lstlisting}
% \usepackage{ex-footnote}
% \usepackage[format=fnsymbol]{ex-footnote}
% \usepackage[color=green]{ex-footnote}
% \usepackage[color=red,format=roman]{ex-footnote}
% \end{lstlisting}
%
%
% \subsection{Bugs}
%
% If you happen to find bugs, it'd be great if you let me know. Just write me an
% email (see the front page) or submit a bug report on GitHub:
% \url{https://github.com/Skillmon/tex_expkv-opt}
%
%
% \subsection{License}
%
% Copyright \textcopyright\ 2020\unless\ifnum\year=2020--\the\year\fi\
% Jonathan P. Spratte
%
% \medskip\noindent
% This work 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:
%
% \url{http://www.latex-project.org/lppl.txt}
%
% \noindent
% This work is ``maintained'' (as per LPPL maintenance status) by
%
% \mbox{Jonathan P. Spratte}.
%
% \end{documentation}^^A=<<
%
% \begin{implementation}^^A>>=
%
% \clearpage
%
%
% \section{Implementation}
%
% \gobbledocstriptag
%<*pkg>
%
% First we check whether the \LaTeXe\ kernel supports raw options. If it doesn't
% we check whether a specific version was requested, and if that's not the case
% we manually run |\pkgcls@parse@date@arg| with the last version that supported
% non-raw options.
%    \begin{macrocode}
\IfFormatAtLeastTF{2021/05/01}
  {}
  {%
    \ifx\pkgcls@targetlabel\@empty
      \ifnum\requestedLaTeXdate=\pkgcls@targetdate
        \pkgcls@parse@date@arg{=v0.1}%
      \fi
    \fi
  }
%    \end{macrocode}
% Then we tell \LaTeXe\ where to find which release so that the package rollback
% code of \LaTeXe\ can do its thing.
%    \begin{macrocode}
\DeclareRelease{v0.1}{2020/10/10}{expkv-opt-2020-10-10.sty}
\DeclareCurrentRelease{v0.2}{2021/04/04}
%    \end{macrocode}
% 
% Start the package with the typical \LaTeX\ standards.
% 
% \begin{macro}{\ekvoVersion,\ekvoDate}
%   Store the packages version and date in two macros.
%    \begin{macrocode}
\newcommand*\ekvoVersion{0.2}
\newcommand*\ekvoDate{2021-04-04}
%    \end{macrocode}
% \end{macro}
% And we report who we are and what we need.
%    \begin{macrocode}
\ProvidesPackage{expkv-opt}
  [%
    \ekvoDate\space v\ekvoVersion\space
    parse class and package options with expkv%
  ]
\RequirePackage{expkv}
%    \end{macrocode}
%
%
% \subsection{Loop}
%
% \begin{macro}[internal]
%   {\ekvo@CurrentOption@loop,\ekvo@CurrentOption@loop@,\ekvo@end@loop}
%   We'll need some loop which can iterate over a comma separated list. The loop
%   is very basic and only works for commas of category~12. First we insert the
%   delimiters for the actual loop.
%    \begin{macrocode}
\protected\long\def\ekvo@CurrentOption@loop#1#2%
  {%
    \ekvo@CurrentOption@loop@#2\ekv@mark#1,\ekv@stop,\ekvo@tail
  }
%    \end{macrocode}
%   The actual loop checks whether the final element has been read and if so
%   ends the loop. Else blank elements are ignored, |\CurrentOption| is set and
%   the macro which parses the list elements called. Then call the next
%   iteration.
%    \begin{macrocode}
\long\def\ekvo@CurrentOption@loop@#1#2,%
  {%
    \ekv@gobble@from@mark@to@stop#2\ekvo@end@loop\ekv@stop
    \ekv@ifblank{#2}%
      {}%
      {%
        \edef\CurrentOption{\unexpanded\expandafter{\@gobble#2}}%
        #1{#2}%
      }%
    \ekvo@CurrentOption@loop@#1\ekv@mark
  }
\long\def\ekvo@end@loop#1\ekvo@tail{}
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{Tests}
%
% \begin{macro}[internal]{\ekvo@ifx@TF,\ekvo@ifx@F}
%   We'll need branching |\ifx| tests so that user input containing unbalanced
%   \TeX\ ifs doesn't break (at least not because of us, everything else is the
%   fault of \LaTeXe).
%    \begin{macrocode}
\def\ekvo@ifx@TF#1#2{\ifx#1#2\ekv@fi@firstoftwo\fi\@secondoftwo}
\def\ekvo@ifx@F#1#2{\ifx#1#2\ekv@fi@gobble\fi\@firstofone}
%    \end{macrocode}
% \end{macro}
% 
% \begin{macro}[internal]{\ekvo@do@with@set,\ekvo@name,\ekvo@setname}
%   This test checks whether the \set\ is defined.  If it is we store it in
%   |\ekvo@setname| and set |\ekvo@name| to a short cut to get the \key's
%   callback name. Next we execute the code in |#2|, if the \set\ isn't defined
%   |#2| is gobbled.
%    \begin{macrocode}
\protected\def\ekvo@do@with@set#1#2%
  {%
    \ekvifdefinedset{#1}%
      {%
        \expandafter
        \let\expandafter\ekvo@name\csname\ekv@undefined@set{#1}\endcsname
        \def\ekvo@setname{#1}%
        #2%
      }%
      {\ekvo@err@undefined@set{#1}}%
  }
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{Key handlers}
%
% \expkvo\ uses handlers specifying what happens if a parsed \key\ is defined or
% undefined.
%
% \begin{macro}[internal]
%   {\ekvo@handle@undefined@k@pkg,\ekvo@handle@undefined@kv@pkg}
%   The case for undefined keys in a local list of a package is easy, just throw
%   appropriate errors.
%    \begin{macrocode}
\protected\long\def\ekvo@handle@undefined@k@pkg#1%
  {%
    \ekv@ifdefined{\ekvo@name{#1}}%
      {\ekvo@err@value@required{#1}}%
      {\ekvo@err@undefined@key{#1}}%
  }
\def\ekvo@handle@undefined@kv@pkg#1#2%
  {%
    \ekv@ifdefined{\ekvo@name{#1}N}%
      {\ekvo@err@value@forbidden{#1}}%
      {\ekvo@err@undefined@key{#1}}%
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]
%   {
%     \ekvo@addto@unused@one,\ekvo@addto@unused@two,
%     \ekvo@rmfrom@unused@one,\ekvo@rmfrom@unused@two
%   }
%   These macros will add or remove the |\CurrentOption| to or from the list of
%   unused global options. Since |\ekvo@do@unusedoptionlist| will have some
%   overhead before calling the list changing macro in filtering the current
%   option, we use an optimization here in that we check whether the list is
%   empty before calling the |rmfrom| function.
%    \begin{macrocode}
\long\def\ekvo@addto@unused@one#1{\ekvo@do@unusedoptionlist\ekvo@addto@list}
\long\def\ekvo@addto@unused@two#1#2{\ekvo@do@unusedoptionlist\ekvo@addto@list}
\long\def\ekvo@rmfrom@unused@one#1%
  {%
    \ekvo@ifx@F\@unusedoptionlist\@empty
      {\ekvo@do@unusedoptionlist\ekvo@rmfrom@list}%
  }
\long\def\ekvo@rmfrom@unused@two#1#2%
  {%
    \ekvo@ifx@F\@unusedoptionlist\@empty
      {\ekvo@do@unusedoptionlist\ekvo@rmfrom@list}%
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]
%   {
%     \ekvo@do@unusedoptionlist,
%     \ekvo@prepare@unusedoption,
%     \ekvo@prepare@unusedoption@a,
%     \ekvo@prepare@unusedoption@b,
%     \ekvo@prepare@unusedoption@c
%   }
%   The way the new \LaTeXe\ kernel handles the unused option list changed. Now
%   not the entire |\CurrentOption| is listed, but just everything up to the
%   first equals sign, and spaces got zapped, doesn't matter whether the raw
%   option list gets used or not. So we have to zap spaces and remove everything
%   from the first equals sign onwards. The code used here will fail if the
%   current option contains an |\ekv@mark| or |\ekv@stop| before the first
%   equals sign (this seems rather unlikely).
%    \begin{macrocode}
\protected\def\ekvo@do@unusedoptionlist#1%
  {%
    \let\ekvo@unpreparedCurrentOption\CurrentOption
    \edef\CurrentOption
      {\expandafter\ekvo@prepare@unusedoption\CurrentOption=\ekv@mark}%
    #1\@unusedoptionlist
    \let\CurrentOption\ekvo@unpreparedCurrentOption
  }
\def\ekvo@prepare@unusedoption{\ekvo@prepare@unusedoption@a\@empty}
\def\ekvo@prepare@unusedoption@a#1%
  {%
    \long\def\ekvo@prepare@unusedoption@a##1=##2\ekv@mark
      {%
        \ekvo@prepare@unusedoption@b##1\ekv@stop
          \ekv@mark\ekvo@prepare@unusedoption@b
          #1\ekv@mark\ekvo@prepare@unusedoption@c
      }%
  }
\ekvo@prepare@unusedoption@a{ }
\long\def\ekvo@prepare@unusedoption@b#1 #2\ekv@mark#3{#3#1#2\ekv@mark#3}
\long\def\ekvo@prepare@unusedoption@c
    #1\ekv@stop
    \ekv@mark\ekvo@prepare@unusedoption@b\ekv@mark\ekvo@prepare@unusedoption@c
  {\unexpanded\expandafter{#1}}
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]
%   {
%     \ekvo@set@handlers@local,\ekvo@set@handlers@global,
%     \ekvo@set@handlers@list
%   }
%   These macros are boring. They just set up the handlers to respect the rules
%   documented earlier.
%    \begin{macrocode}
\protected\def\ekvo@set@handlers@local
  {%
    \ekvo@if@need@handlers
      {%
        \ifx\@currext\@clsextension
          \ifx\@classoptionslist\relax
            \let\ekvo@handle@undefined@k\@gobble
            \let\ekvo@handle@undefined@kv\@gobbletwo
          \else
            \expandafter
            \ifx
                \csname @raw@opt@\@currname.\@currext\endcsname
                \@raw@classoptionslist
              \let\ekvo@handle@undefined@k\ekvo@addto@unused@one
              \let\ekvo@handle@undefined@kv\ekvo@addto@unused@two
            \else
              \let\ekvo@handle@undefined@k\@gobble
              \let\ekvo@handle@undefined@kv\@gobbletwo
            \fi
          \fi
        \else
          \let\ekvo@handle@undefined@k\ekvo@handle@undefined@k@pkg
          \let\ekvo@handle@undefined@kv\ekvo@handle@undefined@kv@pkg
        \fi
      }%
  }
\protected\def\ekvo@set@handlers@global
  {%
    \unless\ifx\@unusedoptionlist\@empty
      \let\ekvo@handle@defined@k\ekvo@rmfrom@unused@one
      \let\ekvo@handle@defined@kv\ekvo@rmfrom@unused@two
    \fi
    \ekvo@if@need@handlers
      {%
        \let\ekvo@handle@undefined@k\@gobble
        \let\ekvo@handle@undefined@kv\@gobbletwo
      }%
  }
\protected\def\ekvo@set@handlers@list
  {%
    \ekvo@if@need@handlers
      {%
        \let\ekvo@handle@undefined@k\@gobble
        \let\ekvo@handle@undefined@kv\@gobbletwo
      }%
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]{\ekvo@if@need@handlers,\ekvo@dont@need@handlers}
%   If the user specifies handlers this macro will be let to
%   |\ekvo@dont@need@handlers|, which will act like |\@gobble| and also let it
%   to |\@firstofone| afterwards.
%    \begin{macrocode}
\let\ekvo@if@need@handlers\@firstofone
\protected\long\def\ekvo@dont@need@handlers#1%
  {%
    \let\ekvo@if@need@handlers\@firstofone
  }%
%    \end{macrocode}
% \end{macro}
%
% We have to set the default for the handlers of defined keys, because they
% don't necessarily get defined before a list is parsed.
%    \begin{macrocode}
\let\ekvo@handle@defined@k\@gobble
\let\ekvo@handle@defined@kv\@gobbletwo
%    \end{macrocode}
%
%
% \subsection{Processing list elements}
%
% \begin{macro}[internal]{\ekvo@process@common}
%   All the key processing frontend macros use the same basic structure. |#1|
%   will be a simple test, deciding whether the list will really be parsed or
%   not, |#3| will be the \set, and |#2| will be the individual code of the
%   frontend macro which should be executed if both the test in |#1| is true and
%   the \set\ is defined.
%    \begin{macrocode}
\protected\def\ekvo@process@common#1#2#3%
  {%
    #1{\ekvo@do@with@set{#3}{#2}}%
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]{\ekvo@process@list}
%   This macro only expands the list holding macro and forwards it to the
%   loop macro.
%    \begin{macrocode}
\protected\def\ekvo@process@list#1%
  {%
    \expandafter\ekvo@CurrentOption@loop\expandafter{#1}\ekvo@parse
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]{\ekvo@parse}
%   This macro calls internals of |\ekvparse| such that the code splitting at
%   commas isn't executed, else this is equivalent to
%   |\ekvparse\ekvo@set@k\ekvo@set@kv{#1}|.
%    \begin{macrocode}
\protected\long\def\ekvo@parse#1%
  {%
    \ekv@eq@other#1\ekv@nil\ekv@mark\ekv@parse@eq@other@a
      =\ekv@mark\ekv@parse@eq@active
    \ekvo@set@k\ekvo@set@kv
    \ekvo@tail
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]{\ekvo@set@k,\ekvo@set@kv}
%   These two macros check whether the key is defined and if so call the handler
%   for defined keys and execute the key, else the handler for undefined keys is
%   called. They have to clean up a bit of code which is left by |\ekvo@parse|.
%    \begin{macrocode}
\protected\def\ekvo@set@k#1#2\ekvo@tail
  {%
    \ekv@ifdefined{\ekvo@name{#1}N}%
      {%
        \ekvo@handle@defined@k{#1}%
        \csname\ekvo@name{#1}N\endcsname
      }%
      {\ekvo@handle@undefined@k{#1}}%
  }
\protected\def\ekvo@set@kv#1#2#3\ekvo@tail
  {%
    \ekv@ifdefined{\ekvo@name{#1}}%
      {%
        \ekvo@handle@defined@kv{#1}{#2}%
        \csname\ekvo@name{#1}\endcsname{#2}%
      }%
      {\ekvo@handle@undefined@kv{#1}{#2}}%
  }
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{List variable helpers}
%
% \begin{macro}[internal]{\ekvo@addto@list}
%   This macro is rather simple. If the list to which the |\CurrentOption|
%   should be added is empty we can just let the list to the |\CurrentOption|.
%   Else we have to expand the list once and the |\CurrentOption| once.
%    \begin{macrocode}
\protected\def\ekvo@addto@list#1%
  {%
    \ekvo@ifx@TF#1\@empty
      {\let#1\CurrentOption}%
      {%
        \edef#1%
          {%
            \unexpanded\expandafter{#1},%
            \unexpanded\expandafter{\CurrentOption}%
          }%
      }%
  }
%    \end{macrocode}
% \end{macro}
%
% \begin{macro}[internal]{\ekvo@rmfrom@list,\ekvo@rmfrom@list@}
%   This works by looping over every list item and comparing it to
%   |\ekvo@curropt| which stores the real |\CurrentOption|. This is
%   comparatively slow, but works for items containing braces unlike what
%   \LaTeXe\ does. We could be faster for items not containing braces, though.
%    \begin{macrocode}
\protected\def\ekvo@rmfrom@list#1%
  {%
    \ekvo@ifx@F#1\@empty
      {%
        \let\ekvo@tmp@list\@empty
        \let\ekvo@curropt\CurrentOption
        \expandafter\ekvo@CurrentOption@loop\expandafter{#1}\ekvo@rmfrom@list@
        \let\CurrentOption\ekvo@curropt
        \let#1\ekvo@tmp@list
      }%
  }
\protected\long\def\ekvo@rmfrom@list@#1%
  {%
    \ekvo@ifx@F\CurrentOption\ekvo@curropt
      {\ekvo@addto@list\ekvo@tmp@list}%
  }
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{Errors}
%
% \begin{macro}[internal]
%   {
%     \ekvo@err@undefined@key,\ekvo@err@value@required,
%     \ekvo@err@value@forbidden,\ekvo@err@undefined@set
%   }
%   Just some macros to throw errors in the few cases an error has to be thrown.
%    \begin{macrocode}
\protected\def\ekvo@err@undefined@key#1%
  {%
    \PackageError{expkv-opt}{Undefined key `#1' in set `\ekvo@setname'}{}%
  }
\protected\def\ekvo@err@value@required#1%
  {%
    \PackageError{expkv-opt}%
      {Value required for key `#1' in set `\ekvo@setname'}%
      {}%
  }
\protected\def\ekvo@err@value@forbidden#1%
  {%
    \PackageError{expkv-opt}%
      {Value forbidden for key `#1' in set `\ekvo@setname'}%
      {}%
  }
\protected\def\ekvo@err@undefined@set#1%
  {%
    \PackageError{expkv-opt}%
      {Undefined set `#1'}%
      {The set for which you try to parse options isn't defined in expkv.}%
  }
%    \end{macrocode}
% \end{macro}
%
%
% \subsection{User Interface}
%
% The user interface macros just put together the bits and pieces.
% \begin{macro}{\ekvoProcessLocalOptions}
%    \begin{macrocode}
\protected\def\ekvoProcessLocalOptions
  {%
    \ekvo@process@common
      {\ekv@ifdefined{@raw@opt@\@currname.\@currext}\@firstofone\@gobble}%
      {%
        \ekvo@set@handlers@local
        \expandafter
        \ekvo@process@list\csname @raw@opt@\@currname.\@currext\endcsname
        \AtEndOfPackage{\let\@unprocessedoptions\relax}%
      }%
  }
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\ekvoProcessGlobalOptions}
%    \begin{macrocode}
\protected\def\ekvoProcessGlobalOptions
  {%
    \ekvo@process@common{\ekvo@ifx@F\@classoptionslist\relax}%
      {%
        \ekvo@set@handlers@global
        \ekvo@process@list\@raw@classoptionslist
        \let\ekvo@handle@defined@k\@gobble
        \let\ekvo@handle@defined@kv\@gobbletwo
      }%
  }
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\ekvoProcessUnusedGlobalOptions}
%    \begin{macrocode}
\protected\def\ekvoProcessUnusedGlobalOptions#1%
  {%
    \PackageWarning{expkv-opt}%
      {This macro no longer works because of changes in the LaTeX2e kernel.}%
  }
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\ekvoProcessOptionsList}
%    \begin{macrocode}
\protected\def\ekvoProcessOptionsList#1%
  {%
    \ekvo@process@common{\ekvo@ifx@F#1\@empty}%
      {%
        \ekvo@set@handlers@list
        \ekvo@process@list#1%
      }%
  }
%    \end{macrocode}
% \end{macro}
% \begin{macro}{\ekvoUseUnknownHandlers}
%    \begin{macrocode}
\protected\def\ekvoUseUnknownHandlers
  {\@ifstar\ekvoUseUnknownHandlers@s\ekvoUseUnknownHandlers@n}
\protected\def\ekvoUseUnknownHandlers@s
  {%
    \def\ekvo@handle@undefined@k
      {%
        \ekv@ifdefined{\ekvo@name{}uN}%
          {\csname\ekvo@name{}uN\endcsname}%
          {\@gobble}%
      }%
    \long\def\ekvo@handle@undefined@kv##1##2%
      {%
        \ekv@ifdefined{\ekvo@name{}u}%
          {\csname\ekvo@name{}u\endcsname{##2}{##1}}%
          {}%
      }%
    \let\ekvo@if@need@handlers\ekvo@dont@need@handlers
  }
\protected\def\ekvoUseUnknownHandlers@n#1#2%
  {%
    \let\ekvo@handle@undefined@k#1\relax
    \let\ekvo@handle@undefined@kv#2\relax
    \let\ekvo@if@need@handlers\ekvo@dont@need@handlers
  }
%    \end{macrocode}
% \end{macro}
%
% All user interface macros should be only used in the preamble.
%    \begin{macrocode}
\@onlypreamble\ekvoProcessLocalOptions
\@onlypreamble\ekvoProcessGlobalOptions
\@onlypreamble\ekvoProcessUnusedGlobalOptions
\@onlypreamble\ekvoProcessOptionsList
\@onlypreamble\ekvoUseUnknownHandlers
%    \end{macrocode}
% 
% \gobbledocstriptag
%</pkg>
%
% \end{implementation}^^A=<<
%
% \clearpage
% \PrintIndex
%
% \Finale
\endinput
%
^^A vim: ft=tex fdm=marker fmr=>>=,=<<
