% \iffalse meta-comment
% ======================================================================
% scrkernel-paragraphs.dtx
% Copyright (c) Markus Kohm, 2002-2025
%
% This file is part of the LaTeX2e KOMA-Script bundle.
%
% This work may be distributed and/or modified under the conditions of
% the LaTeX Project Public License, version 1.3c of the license.
% The latest version of this license is in
%   http://www.latex-project.org/lppl.txt
% and version 1.3c or later is part of all distributions of LaTeX 
% version 2005/12/01 or later and of this work.
%
% This work has the LPPL maintenance status "author-maintained".
%
% The Current Maintainer and author of this work is Markus Kohm.
%
% This work consists of all files listed in MANIFEST.md.
% ======================================================================
%%% From File: $Id: scrkernel-paragraphs.dtx 4145 2025-05-13 16:54:14Z kohm $
%<option>%%%            (run: option)
%<body>%%%            (run: body)
%<*dtx>
\ifx\ProvidesFile\undefined\def\ProvidesFile#1[#2]{}\fi
\begingroup
  \def\filedate$#1: #2-#3-#4 #5${\gdef\filedate{#2/#3/#4}}
  \filedate$Date: 2025-05-13 18:54:14 +0200 (Di, 13. Mai 2025) $
  \def\filerevision$#1: #2 ${\gdef\filerevision{r#2}}
  \filerevision$Revision: 4145 $
  \edef\reserved@a{%
    \noexpand\endgroup
    \noexpand\ProvidesFile{scrkernel-paragraphs.dtx}%
                          [\filedate\space\filerevision\space
                           KOMA-Script
                           (paragraphs)]
  }%
\reserved@a
\documentclass[USenglish]{koma-script-source-doc}
\usepackage{babel}
\setcounter{StandardModuleDepth}{3}
\begin{document}
\DocInput{scrkernel-paragraphs.dtx}
\end{document}
%</dtx>
% \fi
%
% \changes{v2.95}{2002/06/25}{first version after splitting \file{scrclass.dtx}}
% \changes{v3.36}{2022/03/07}{switch over from \cls*{scrdoc} to
%   \cls*{koma-script-source-doc}}
% \changes{v3.36}{2022/03/07}{whole implementation documentation in English}
% \changes{v3.40}{2023/04/17}{guide names changed}
%
% \GetFileInfo{scrkernel-paragraphs.dtx}
% \title{The Code Related to Paragraph Building and Page Building of
%   \href{https://komascript.de}{\KOMAScript} Classes}
% \author{\href{mailto:komascript@gmx.info}{Markus Kohm}}
% \date{Revision \fileversion{} of \filedate}
% \maketitle
% \begin{abstract}
%   \file{scrkernel-paragraphs.dtx} does all the things about configuration of
%   paragraphs and page breaking. Some of them are very special for
%   \KOMAScript.
% \end{abstract}
% \tableofcontents
%
% \section{User Manual}
%
% You can find the user documentation the commands implemented here in the
% \KOMAScript{} manual, either the German \file{scrguide-de.pdf} or the
% English \file{scrguide-en.pdf}.
%
% \MaybeStop{\PrintIndex}
%
% \section{Implementation of Paragraphs and Pages}
%
% Almost all of this code is for the classes only.
%    \begin{macrocode}
%<*class>
%    \end{macrocode}
%
% \subsection{Options and macros to handle the paragraph layout}
%
% Already from version 2.8i \KOMAScript can handle paragraph skips instead of
% indenting paragraphs. But the corresponding code has changed a lot over the
% years.
%
% \begin{command}{\setparsizes}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.17}{2015/03/10}{support for internal option value storage}
% \changes{v3.19}{2015/07/29}{\cs{par@update} should not reset itself to
%   \cs{default@par@update} in the document preamble}
% \changes{v3.39}{2022/11/11}{initial dot removed from member argument of
%   option storage commands}
% \begin{macro}{\f@parindent}
% \changes{v2.95}{2004/11/05}{added}
% \begin{macro}{\f@parskip,\f@parfillskip}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v2.95}{2004/11/05}{meaning changed}
% \begin{macro}{\scr@parindent}
% \changes{v2.95}{2004/11/05}{added}
% \begin{macro}{\scr@parskip,\scr@parfillskip}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v2.95}{2004/11/05}{meaning changed}
% Command
% \begin{quote}
%   \cs{setparsizes}\marg{indent}\marg{skip}\marg{fill}
% \end{quote}
% not only sets the three main paragraph parameters of \TeX: \len{parskip},
% \len{parindent}, \len{parfillskip}. Because of option \opt{parskip=relative}
% it has to use a kind of delayed setting of these parameters at least at the
% document preamble. So these settings are not activated until
% \cs{selectfont}. To do so, not the \TeX{} parameters are changed, but the
% current values of the \TeX{} parameters are stored to \cs{f@parindent},
% \cs{f@parskip} and \cs{f@parfillskip} and the new values are stored to
% \cs{scr@parindent}, \cs{scr@parskip} and \cs{scr@parfillskip}
% only. Additionally \cs{par@update} is used to activate these new
% values. Later we will use a hook to automatically execute \cs{par@update}
% with every \cs{selectfont}. The current value storage is initialized twice:
% First immediately and second inside at the end of the class.
% \begin{description}
% \item[ToDo:] Is the second initialization really needed? Wouldn't it be done
%   with the class options? Here user changes are not to be expected, because
%   we are still inside the class and therefore there is no user interaction.
% \end{description}
% \begin{macro}{\par@update}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.20}{2016/02/22}{\cs{AtBeginDocument} code added}
% \begin{macro}{\default@par@update}
% \changes{v2.95}{2004/11/05}{added}
% \begin{macro}{\par@updaterelative}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.36}{2022/03/07}{using \cs{reserved@a} instead of \cs{@tempa}}
% \begin{macro}{\parindent@update,\parskip@update,\parfillskip@update}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.36}{2022/03/07}{using \cs{reserved@a} and \cs{reserved@b}
%   instead if \cs{@tempa} and \cs{@tempb}}
% The initial \cs{par@update} action is to do nothing. But with
% \opt{parskip=relative} it always and after \cs{setparsizes} it once (or in
% the document preamble also always) has to reactivate the new values. This is
% done using \cs{default@par@update} and
% \cs{par@updaterelative}. \cs{default@par@update} is either a do nothing
% (\opt{parskip=absolute}) or \cs{par@updaterelative}
% (\opt{parskip=relative}). \cs{par@updaterelative} does the real update.
% \begin{description}
% \item[ToDo:] Sometimes internally \cs{par@updaterelative} is used instead of
%   \cs{selectfont} to do an immediate update after \cs{setparsizes}. But is
%   this correct? Wouldn't be \cs{selectfont} the correct action, to also
%   reset the definition of \cs{par@update}?
% \item[ToDO:] Does the \cs{AtBeginCode} execution of \cs{par@update} make
%   sense? The \cs{par@update} is done after the initial \cs{normalsize} and
%   the initial \cs{selectfont}. So shouldn't this be enough?
% \end{description}
%    \begin{macrocode}
%<*option>
\newcommand*{\setparsizes}[3]{%
  \edef\f@parindent{\the\parindent}%
  \edef\f@parskip{\the\parskip}%
  \edef\f@parfillskip{\the\parfillskip}%
  \def\scr@parindent{#1}%
  \def\scr@parskip{#2}%
  \def\scr@parfillskip{#3}%
  \def\par@update{%
    \if@atdocument\let\par@update\default@par@update\fi
    \par@updaterelative
  }%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{false}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{never}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{full}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{full-}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{full+}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{full*}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{half}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{half-}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{half+}%
  \KOMA@kav@remove{\KOMAClassFileName}{parskip}{half*}%
}
\newcommand*{\f@parindent}{\the\parindent}
\newcommand*{\f@parskip}{\the\parskip}
\newcommand*{\f@parfillskip}{\the\parfillskip}
\newcommand*{\scr@parindent}{1em}
\newcommand*{\scr@parskip}{\z@}
\newcommand*{\scr@parfillskip}{\z@ \@plus 1fil}
\AtEndOfClass{%
  \edef\f@parindent{\the\parindent}%
  \edef\f@parskip{\the\parskip}%
  \edef\f@parfillskip{\the\parfillskip}%
}
\newcommand*{\par@update}{}
\let\par@update\relax
\newcommand*{\default@par@update}{}
\let\default@par@update\relax
\AtBeginDocument{\par@update}
%</option>
%    \end{macrocode}
% Because of the currently complicated initialization, i.e., when switching
% between \cs{parskip=absolute} and \cs{parskip=relative}, we currently define
% \cs{par@updaterelative} not before the class options has been processed. New
% values are only set, if between the last \cs{setparsizes} and the current
% \cs{par@updaterelative} (e.g. inside \cs{selectfont}) the user has not
% changed the \TeX{} variables. If he has changed the \TeX{} variables instead
% of using \cs{setparsizes} we think, he does not want any other change. And
% because of to be able to do the tests inside a group without permanent
% change of \cs{reserved@a} we use three additional helpers.
%    \begin{macrocode}
%<*body>
\newcommand*{\par@updaterelative}{%
  \begingroup
    \edef\reserved@a{\the\parindent}\ifx\reserved@a\f@parindent
      \aftergroup\parindent@update
%<*trace>
    \else
      \ClassInfo{\KOMAClassName}{\string\parindent\space not changed}%
%</trace>
    \fi
    \edef\reserved@a{\the\parskip}\ifx\reserved@a\f@parskip
      \aftergroup\parskip@update
%<*trace>
    \else
      \ClassInfo{\KOMAClassName}{\string\parskip\space not changed}%
%</trace>
    \fi
    \edef\reserved@a{\the\parfillskip}\ifx\reserved@a\f@parfillskip
      \aftergroup\parfillskip@update
%<*trace>
    \else
      \ClassInfo{\KOMAClassName}{\string\parfillskip\space not changed}%
%</trace>
    \fi
  \endgroup
}
\newcommand*{\parindent@update}{%
  \scr@defaultunits\parindent\scr@parindent
  \begingroup
    \let\reserved@b\endgroup
    \edef\reserved@a{\the\parindent}\ifx\reserved@a\f@parindent\else
      \def\reserved@b{\endgroup\edef\f@parindent{\the\parindent}}%
%<trace>      \ClassInfo{\KOMAClassName}{\string\parindent=\the\parindent}%
    \fi
  \reserved@b
}
\newcommand*{\parskip@update}{%
  \scr@defaultunits\parskip\scr@parskip
  \begingroup
    \let\reserved@b\endgroup
    \edef\reserved@a{\the\parskip}\ifx\reserved@a\f@parskip\else
      \def\reserved@b{\endgroup\edef\f@parskip{\the\parskip}}%
%<trace>      \ClassInfo{\KOMAClassName}{\string\parskip=\the\parskip}%
    \fi
  \reserved@b
}
\newcommand*{\parfillskip@update}{%
  \scr@defaultunits\parfillskip\scr@parfillskip
  \begingroup
    \let\reserved@b\endgroup
    \edef\reserved@a{\the\parfillskip}\ifx\reserved@a\f@parfillskip\else
      \def\reserved@b{\endgroup\edef\f@parfillskip{\the\parfillskip}}%
%<trace>      \ClassInfo{\KOMAClassName}{\string\parfillskip=\the\parfillskip}%
    \fi
  \reserved@b
}
%</body>
%    \end{macrocode}
% \end{macro}^^A \parindent@update,\parskip@update,\parfillskip@update}
% \end{macro}^^A \par@updaterelative
% \end{macro}^^A \default@par@update
% \end{macro}^^A \par@update
% \end{macro}^^A \scr@parskip,\scr@parfillskip
% \end{macro}^^A \scr@parindent
% \end{macro}^^A \f@parskip,\f@parfillskip
% \end{macro}^^A \f@parindent
% \end{command}^^A \setparsizes
%
% \begin{option}{parskip}
% \changes{v2.8i}{2001/07/22}{added}
% \changes{v2.95}{2006/03/11}{changed into \pkg{keyval} option}
% \changes{v3.08}{2010/12/14}{value \opt{\quotechar=never} added}
% \changes{v3.12}{2013/03/05}{using \cs{FamilyKeyState}.}
% \changes{v3.17}{2015/03/10}{using value storage}
% \changes{v3.25}{2017/09/27}{typo fix in \cs{FamilyKeyStateUnknownValue}}
% \changes{v3.26b}{2019/02/01}{\cs{baselineskip} replaced by 1\cs{baselineskip}}
% \changes{v3.39}{2022/11/11}{initial dot removed from member argument of
%   option storage commands}
% \begin{option}{parindent,parskip-,parskip+,parskip*,
%                halfparskip,halfparskip-,halfparskip+,halfparskip*}
% \changes{v2.8i}{2001/07/22}{added}
% \changes{v2.95}{2006/03/11}{obsolete}
% \changes{v2.97d}{2007/10/03}{\cs{PackageInfo} replaced by
%   \cs{PackageInfoNoLine}}
% \changes{v3.01a}{2008/11/20}{deprecated}
% \changes{v3.99}{2022/11/16}{removed from \KOMAScript~4}
% Originally we have had nine options for all the paragraph indent and skip
% settings. Using \pkg*{scrbase} we have only one option with additional
% settings for relative and absolute values and paragraph indent without glue
% for paragraph skip.
%    \begin{macrocode}
%<*option>
\KOMA@key{parskip}[true]{%
  \begingroup
    \KOMA@set@ncmdkey{parskip}{@tempa}{%
      {never}{0},%
      {false}{1},{off}{1},{no}{1},%
      {full-}{2},%
      {half-}{3},%
      {full}{4},{true}{4},{on}{4},{yes}{4},%
      {half}{5},%
      {full+}{6},%
      {half+}{7},%
      {full*}{8},%
      {half*}{9},%
      {relative}{10},%
      {absolute}{11}%
    }{#1}%
    \ifx\FamilyKeyState\FamilyKeyStateProcessed
      \aftergroup\FamilyKeyStateProcessed
      \ifcase\number\@tempa% 0
        \endgroup
        \setparsizes{1em}{\z@}{\z@ \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{never}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 1
        \endgroup
        \setparsizes{1em}{\z@ \@plus \p@}{\z@ \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{false}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 2
        \endgroup
        \setparsizes{\z@}{1\baselineskip \@plus .1\baselineskip}{%
          \z@ \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{full-}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 3
        \endgroup
        \setparsizes{\z@}{.5\baselineskip \@plus .5\baselineskip}{%
          \z@ \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{half-}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 4
        \endgroup
        \setparsizes{\z@}{1\baselineskip \@plus .1\baselineskip}{%
          1em \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{full}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 5
        \endgroup
        \setparsizes{\z@}{.5\baselineskip \@plus .5\baselineskip}{%
          1em \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{half}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 6
        \endgroup
        \setparsizes{\z@}{1\baselineskip \@plus .1\baselineskip}{%
          .3333\linewidth\@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{full+}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 7
        \endgroup
        \setparsizes{\z@}{.5\baselineskip \@plus .5\baselineskip}{%
          .3333\linewidth \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{half+}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 8
        \endgroup
        \setparsizes{\z@}{1\baselineskip \@plus .1\baselineskip}{%
          .25\linewidth \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{full*}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 9
        \endgroup
        \setparsizes{\z@}{.5\baselineskip \@plus .5\baselineskip}{%
          .25\linewidth \@plus 1fil}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{half*}%
        \if@atdocument\AfterKOMAoptions{\selectfont}\fi
      \or% 10
        \endgroup
        \KOMA@kav@remove{\KOMAClassFileName}{parskip}{absolute}%
        \KOMA@kav@remove{\KOMAClassFileName}{parskip}{relative}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{relative}%
        \ifx\par@updaterelative\undefined
          \expandafter\AtEndOfClass
        \else
          \expandafter\@firstofone
        \fi
        {%
          \ifx\par@update\default@par@update
            \let\par@update\par@updaterelative
          \fi
          \let\default@par@update=\par@updaterelative
        }%
      \or%11
        \endgroup
        \KOMA@kav@remove{\KOMAClassFileName}{parskip}{absolute}%
        \KOMA@kav@remove{\KOMAClassFileName}{parskip}{relative}%
        \KOMA@kav@add{\KOMAClassFileName}{parskip}{absolute}%
        \ifx\par@updaterelative\undefined
          \expandafter\AtEndOfClass
        \else
          \expandafter\@firstofone
        \fi
        {%
          \ifx\par@update\default@par@update
            \let\par@update\relax
          \fi
          \let\default@par@update=\relax
        }%
      \else% should never be
        \endgroup
    \fi
  \else
    \endgroup
    \FamilyKeyStateUnknownValue
  \fi
}
%<*!v4>
\KOMA@DeclareDeprecatedOption{parskip-}{parskip=full-}
\KOMA@DeclareDeprecatedOption{parskip+}{parskip=full+}
\KOMA@DeclareDeprecatedOption{parskip*}{parskip=full*}
\KOMA@DeclareDeprecatedOption{halfparskip}{parskip=half}
\KOMA@DeclareDeprecatedOption{halfparskip-}{parskip=half-}
\KOMA@DeclareDeprecatedOption{halfparskip+}{parskip=half+}
\KOMA@DeclareDeprecatedOption{halfparskip*}{parskip=half*}
\KOMA@DeclareDeprecatedOption{parindent}{parskip=false}
%</!v4>
\KOMA@kav@add{\KOMAClassFileName}{parskip}{false}
\KOMA@kav@add{\KOMAClassFileName}{parskip}{absolute}
%</option>
%    \end{macrocode}
% \end{option}^^A parindent … halfparskip*
% \end{option}^^A parskip
%
% \changes{v2.8i}{2001/07/22}{don't change \cs{baselinestretch}}
%
% \begin{length}{\lineskip,\normallineskip}
% The minimum line skip.
%    \begin{macrocode}
%<*body>
\setlength{\lineskip}{\p@}
\setlength{\normallineskip}{\p@}
%    \end{macrocode}
% \end{length}
%
% \begin{command}{\selectfont}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.33}{2021/01/21}{from \LaTeX{} 2021/06/01 use hook instead of
%   patch}
% \changes{v3.44}{2025/05/13}{code for \LaTeX{} before 2021/06/01 removed}
% Because of \opt{parskip=relative} we need a hook to activate the changes of
% the paragraph values. A good place to do so is \cs{selectfont}. With
% \KOMAScript{} 3.00 we needed to patch this command. But from \LaTeX{}
% 2021/06/01 we can use a new generic hook.
%    \begin{macrocode}
\AddToHook{selectfont}{\par@update}%
\AfterPackage{everysel}{%
  \IfPackageAtLeastTF{everysel}{2021/01/18}{}{%
    \ClassError{\KOMAClassName}{%
      incompatible `everysel' detected
    }{%
      You are using an old version of `everysel' in combination with a
      LaTeX\MessageBreak
      version >= 2021/06/01 and KOMA-Script >= 3.33. This combination
      is\MessageBreak
      not supported.\MessageBreak
      You could switch back to an older LaTeX using package
      `latexrelease'.\MessageBreak
      But I recommend to update `everysel'%
    }%
  }%
}%
\AfterPackage{tracefnt}{%
  \IfPackageAtLeastTF{tracefnt}{2020/12/22}{}{%
    \ClassError{\KOMAClassName}{%
      incompatible `tracefnt' detected
    }{%
      `tracefnt' is a LaTeX base package and therefore should be updated
      together\MessageBreak
      with LaTeX kernel. So this should never happen! Please check
      your\MessageBreak
      LaTeX installation%
    }%
  }%
}%
%    \end{macrocode}
% \end{command}^^A \selectfont
%
% \begin{macro}{\scr@selectfont,\scr@new@selectfont}
% \changes{v2.95}{2006/04/14}{added}
% \changes{v3.10}{2010/09/28}{\pkg{everysel} support fixed}
% \changes{v3.10}{2010/09/28}{\pkg{tracefnt} supported}
% \changes{v3.10b}{2011/03/13}{\pkg{everysel} can be loaded inside
%   \cs{begin\{document\}}}
% \changes{v3.44}{2025/05/13}{removed}
% \end{macro}^^A \scr@selectfont,\scr@new@selectfont
%
% \begin{macro}{\scr@defaultunits}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.19}{2015/08/22}{\cs{setlength} replaced because of \pkg{tikz}}
% \begin{macro}{\scr@@defaultunits}
% \changes{v2.95}{2004/11/05}{added}
% \begin{macro}{\scr@@@defaultunits}
% \changes{v2.95}{2004/11/05}{added}
% \changes{v3.19}{2015/08/22}{\cs{setlength} and \cs{addtolength} replaced
%   because of \pkg{tikz}}
% Above we've already used \cs{scr@defaultunits} inside
% \cs{par@updaterelative}. This is very similar to the \LaTeX{} kernel macro
% \cs{@defaultunits}, but accepts dimensions or skips as first and second
% value.
%    \begin{macrocode}
\newcommand*{\scr@defaultunits}[2]{%
  \begingroup
    \edef\@tempa{#2}%
    \expandafter\scr@@defaultunits\expandafter#1\@tempa plusplus\@nnil
    \edef\@tempa{\noexpand\endgroup\noexpand#1\the\glueexpr #1\relax}%
  \@tempa
}
\newcommand*{\scr@@defaultunits}{}
\def\scr@@defaultunits#1#2plus#3plus#4\@nnil{%
  \ifx\relax#3\relax
    \scr@@@defaultunits#1{}#2minusminus\@nnil
  \else
    \scr@@@defaultunits#1{#2}#3minusminus\@nnil
  \fi
}
\newcommand*{\scr@@@defaultunits}{}
\def\scr@@@defaultunits#1#2#3minus#4minus#5\@nnil{%
  \ifx\relax#2\relax
    \@defaultunits\@tempskipa#3pt\relax\@nnil
    #1\@tempskipa
  \else
    \@defaultunits\@tempskipa\z@\@plus#3pt\relax\@nnil
    #1\@tempskipa
    \@defaultunits\@tempskipa#2pt\relax\@nnil
    \advance#1\@tempskipa
  \fi
  \ifx\relax#4\relax\else
    \@defaultunits\@tempskipa\z@\@minus #4pt\relax\@nnil
    \advance#1\@tempskipa
  \fi
}
%</body>
%    \end{macrocode}
% \end{macro}^^A \scr@@@defaultunits
% \end{macro}^^A \scr@@defaultunits
% \end{macro}^^A \scr@defaultunits
%
% \subsection{Extra list code}
%
% \begin{macro}{\@list@extra}
% \changes{v2.8q}{2001/11/06}{added}
% \changes{v2.95c}{2006/08/03}{\len{parsep} fixed}
% \begin{macro}{\add@extra@listi}
% \changes{v2.9h}{2002/09/03}{added}
% Some parameters of lists have to change, depending on the settings for
% paragraphs.
% \begin{description}
% \item[ToDo:] Move this code to \file{scrkernel-listsandtabulars.dtx} or
%   \file{scrkernel-fontsizes.dtx}.
% \end{description}
%    \begin{macrocode}
%<*body>
\newcommand*{\@list@extra}{%
  \ifdim\parskip>\z@\topsep\z@\parsep\parskip\itemsep\z@\fi
}
\newcommand*{\add@extra@listi}[1]{%
  \expandafter\let\csname #1@listi\endcsname=\@listi
  \def\@listi{\csname #1@listi\endcsname\@list@extra}%
}
%</body>
%    \end{macrocode}
% \end{macro}^^A \@list@extra
% \end{macro}^^A \add@extra@listi
%
% \subsection{Patching other packages}
%
% \begin{macro}{\deferred@thm@head}
% \changes{v3.27}{2019/02/10}{new patch of \textsf{amsthm}}
% Unfortunatly \pkg{amsthm} has a problem if a class handles \len{topsep}
% this way, because it is only prepared for the case, that \len{parskip} and
% \len{parsep} are changed manually without influence to \len{topsep}. So the
% initial distance is missing. To avoid this problem, we need to patch the
% package's internal command \cs{deferred@thm@head}. This is not nice, but
% unfortunaltly needed.
% \begin{description}
% \item[ToDo:] Move this code to the package patch code of
%   \file{scrkernel-miscellaneous.dtx} resp. a new file as noted there.
% \end{description}
%    \begin{macrocode}
%<*body>
\AfterPackage{amsthm}{%
  \RequirePackage{xpatch}%
  \xpatchcmd{\deferred@thm@head}{\addvspace{-\parskip}}{}{%
    \ClassInfoNoLine{\KOMAClassName}{%
      amsthm's \string\deferred@thm@head\space patched}%
  }{%
    \ClassWarningNoLine{\KOMAClassName}{%
      cannot patch amsthm's \string\deferred@thm@head.\MessageBreak
      This could result in wrong spacing before theorem\MessageBreak
      environments defined by package `amsthm'%
    }%
  }%
}
%</body>
%    \end{macrocode}
% \end{macro}
% 
% \subsection{Extra code for font sizes}
%
% \begin{description}
% \item[ToDo:] Move this to \file{scrkernel-fontsizes.dtx}.
% \end{description}
%    \begin{macrocode}
%    \end{macrocode}
%
% \changes{v2.98c}{2008/03/26}{changed to be used in font size files}
% \changes{v3.17}{2015/03/25}{update of paragraph settings}
% \begin{macro}{\@listi}
% \changes{v2.98c}{2008/03/27}{\cs{g@addto@macro} replaced by \cs{l@addto@macro}}
% \changes{v3.01}{2008/11/13}{\cs{@listi} wird auf jeden Fall ausgeführt}
% \begin{macro}{\@listI}
% \begin{macro}{\@listii,\@listiii}
% \changes{v2.98c}{2008/03/27}{\cs{g@addto@macro} replaced by \cs{l@addto@macro}}
% \begin{command}{\footnotesize,\small}
% \changes{v2.9h}{2002/09/03}{improved}
% \changes{v2.98c}{2008/03/27}{\cs{g@addto@macro} replaced by \cs{l@addto@macro}}
%    \begin{macrocode}
%</class>
%<*class|clo>
%<*body|10pt|11pt|12pt>
%<*10pt|11pt|12pt>
\@ifundefined{@list@extra}{}{%
  \scr@ifundefinedorrelax{scr@v@is@ge}{\par@updaterelative}{%
    \expandafter\ifnum\scr@v@is@ge{3.17}\par@updaterelative\fi
  }%  
%</10pt|11pt|12pt> 
  \l@addto@macro{\@listi}{\@list@extra}%
  \let\@listI=\@listi
  \l@addto@macro{\@listii}{\@list@extra}%
  \l@addto@macro{\@listiii}{\@list@extra}%
  \l@addto@macro{\footnotesize}{\protect\add@extra@listi{ftns}}%
  \l@addto@macro{\small}{\protect\add@extra@listi{sml}}%
%<10pt|11pt|12pt>}
%<10pt|11pt|12pt>\@listi
%</body|10pt|11pt|12pt>
%</class|clo>
%<*class>
%    \end{macrocode}
% \end{command}
% \end{macro}
% \end{macro}
% \end{macro}
%
%
% \subsection{Page layout parameters}
%
% \begin{length}{\columnsep,\columnseprule}
% Initial column separation. Note, we do not support two column letters. So
% this is not initialized for the letter class.
%    \begin{macrocode}
%<*!letter&body>
\setlength{\columnsep}{10\p@}
\setlength{\columnseprule}{\z@}
%</!letter&body>
%    \end{macrocode}
% \end{length}
%
%
% \subsection{Penalties}
%
% The initial values for the penalties are the same as for the standard classes.
%    \begin{macrocode}
%<*body>
\@lowpenalty  = 51
\@medpenalty  =151
\@highpenalty =301
%</body>
%    \end{macrocode}
%
%
%    \begin{macrocode}
%</class>
%    \end{macrocode}
% 
% \Finale
% \PrintChanges
% 
\endinput
% Local Variables:
% mode: doctex
% ispell-local-dictionary: "en_US"
% eval: (flyspell-mode 1)
% TeX-master: t
% TeX-engine: luatex-dev
% eval: (setcar (or (cl-member "Index" (setq-local TeX-command-list (copy-alist TeX-command-list)) :key #'car :test #'string-equal) (setq-local TeX-command-list (cons nil TeX-command-list))) '("Index" "mkindex %s" TeX-run-index nil t :help "makeindex for dtx"))
% End:

