%  section.cd
%  Anders G S Svensson

%  Source:  section.nw
%           $Revision: 1.25 $
%           $Date: 1996/06/04 12:57:01 $

\def\section@newunnumberedsection@#1#2{
   \section@initsection@{#2}
   \@def@{#2banneru}{%
      \@cs@{section@banner@\@cs@{section@style@#2}}{#2}{}}%
   \@def@{#2}{\section@unnumsect@{#1}{#2}}
   \@ifnext@<{\section@skip@{pre}{#2}%
                      {\@eatspace@{\section@skip@{post}{#2}{}}}}%
             {}}
\let\section@newsection@\section@newunnumberedsection@

\def\section@unnumsect@#1#2#3{%
   \@ifnext@[%
      {\section@@unnumsect@{#1}{#2}{#3}}%
      {\section@@unnumsect@{#1}{#2}{#3}[#3]}}

\def\section@@unnumsect@#1#2#3[#4]{%
   \section@section@{#2}{%
      \section@sectionbanner@{#2}{\@cs@{#2banneru}{#3}}%
      \@expandafter@{\@expandafter@{#1*{toc}{#2}}}%
         \csname section@\@cs@{section@tocchoice@#2}choice@\endcsname{#3}{#4}%
      \@expandafter@{\@expandafter@{\@cs@{#2mark}}}%
         \csname section@\@cs@{section@markchoice@#2}choice@\endcsname{#3}{#4}%
   }\ignorespaces}%
\def\section@skip@#1#2#3<#4>{\relax
   \@ifempty@{#4}%
      {#3}%
      {\@def@{section@#1skip@#2}{\@s@\z@\@sum@\@s@#4+@\vskip\@s@}#3}}

\def\section@newnumberedsection@#1#2{\relax
   \@ifnextchar@*%
      {\@expandafter@{\section@newunnumberedsection@{#1}{#2}}\@eat@}%
      {\section@@newnumberedsection@{#1}{#2}}}

\def\section@@newnumberedsection@#1#2{%
   \section@initsection@{#2}
   \@def@{#2banneru}{%
      \@cs@{section@banner@\@cs@{section@style@#2}}{#2}{}}%
   \@def@{#2banner}{%
      \@cs@{section@banner@\@cs@{section@style@#2}}{#2}{\@cs@{the#2}}}%
   \@ifnext@[%
      {\section@newnumsectwithin@{#1}{#2}}
      {\section@newnumsect@{#1}{#2}}}

\def\section@sectionbanner@#1#2{{\@cs@{section@headinghook@#1}#2}}
\def\section@initsection@#1{%
   \@def@{#1plug}{\defaultsectionplug}
   \@def@{#1mark}{\defaultsectionmark{#1}}
   \@def@{section@markchoice@#1}{\section@markchoice@def@ult}
   \@def@{section@tocchoice@#1}{\section@tocchoice@def@ult}
   \@def@{section@style@#1}{\section@style@def@ult}
   \@def@{section@preskip@#1}{%
      \@s@\z@
      \expandafter\@sum@
      \expandafter\@s@\defaultpresectionskip+@\vskip\@s@}
   \@def@{section@postskip@#1}{%
      \@s@\z@
      \expandafter\@sum@
      \expandafter\@s@\defaultpostsectionskip+@\vskip\@s@}
   \@def@{section@prehook@#1}{\section@prehook@def@ult}%
   \@def@{section@posthook@#1}{\section@posthook@def@ult}%
   \@def@{section@headinghook@#1}{\section@headinghook@def@ult}}

\def\section@define@#1[#2]{%
   \@define@{section@#1@#2}}

\def\section@defvar@#1{\relax
   \@ifnextchar@[{\section@define@{#1}}{\section@define@{#1}[def@ult]}}

\def\presectionhook{\section@defvar@{prehook}}
\def\postsectionhook{\section@defvar@{posthook}}
\def\headinghook{\section@defvar@{headinghook}}

\let\section@prehook@def@ult\relax
\def\section@posthook@def@ult{\penalty200}
\def\section@headinghook@def@ult{\bf}

\let\defaultsectionmark\@eattwo@
\def\defaultsectionplug{\hskip.8em}
\def\defaultpresectionskip{-\lastskip+\bigskipamount+-.5\parskip}
\def\defaultpostsectionskip{\medskipamount+-.5\parskip}

\def\markchoice{\relax
   \@ifnextchar@[%
      {\section@choiceforclass@{mark}}%
      {\section@choiceforclass@{mark}[def@ult]}}
\def\tocchoice{\relax
   \@ifnextchar@[%
      {\section@choiceforclass@{toc}}%
      {\section@choiceforclass@{toc}[def@ult]}}
\def\section@choiceforclass@#1[#2]#3{%
   \@ifundefined@{section@#3choice@}%
      {\@Warning@{Invalid choice: #3}}%
      {\@def@{section@#1choice@#2}{#3}}}

\def\section@markchoice@def@ult{alt}
\def\section@tocchoice@def@ult{full}

\def\section@altchoice@#1#2{{#2}}
\def\section@fullchoice@#1#2{{#1}}
\def\sectionstyle{\relax
   \@ifnextchar@[\section@styleforclass@{\section@styleforclass@[def@ult]}}
\def\section@styleforclass@[#1]{%
   \@afterassignment@{\section@checkstyle@{#1}}\@t@}
\def\section@checkstyle@#1{%
   \@ifundefined@{section@banner@\the\@t@}%
      {\@Warning@{Unknown section style: \the\@t@}}%
      {\@edef@{section@style@#1}{\the\@t@}}}
\def\section@style@def@ult{plain}

\def\section@banner@plain#1#2#3{%
   \noindent
   \@ifempty@{#2}{}{#2\@cs@{#1plug}}#3}
\let\section@banner@p\section@banner@plain

\def\section@banner@word#1#2#3{%
   \noindent
   \@ifempty@{#2}%
      {}%
      {\@ifundefined@{#1word}{}{\@cs@{#1word}\ }#2\@cs@{#1plug}}#3}
\let\section@banner@w\section@banner@word

\def\section@banner@center#1#2#3{%
   \parindent\z@
   \leftskip=0pt plus 1fil \rightskip=0pt plus 1fil
   \parfillskip\z@
   \@ifempty@{#2}{}{#2\@cs@{#1plug}}#3\par}
\let\section@banner@centre\section@banner@center
\let\section@banner@c\section@banner@center

\def\section@banner@centerword#1#2#3{%
   \parindent\z@
   \leftskip=0pt plus 1fil \rightskip=0pt plus 1fil
   \parfillskip\z@
   \@ifempty@{#2}%
      {}%
      {\@ifundefined@{#1word}{}{\@cs@{#1word}\ }#2\@cs@{#1plug}}#3\par}
\let\section@banner@centreword\section@banner@centerword
\let\section@banner@cw\section@banner@centerword
\def\section@newnumsectwithin@#1#2[#3]{
   \newcounter{#2}[#3]
   \@def@{#2}{\section@numsectcs@{#1}{#2}}%
   \@ifnext@<{\section@skip@{pre}{#2}%
                      {\@eatspace@{\section@skip@{post}{#2}{}}}}%
             {}}

\def\section@newnumsect@#1#2{
   \newcounter{#2}
   \@def@{#2}{\section@numsectcs@{#1}{#2}}%
   \@ifnext@<{\section@skip@{pre}{#2}%
                      {\@eatspace@{\section@skip@{post}{#2}{}}}}%
             {}}

\def\section@numsectcs@#1#2{\relax
   \@ifnextchar@*%
      {\section@numsectnonum@{#1}{#2}}%
      {\section@numsect@{#1}{#2}}}

\def\section@numsectnonum@#1#2#3#4{\par
   \@ifnext@[%
      {\section@numsectionnonum@{#1}{#2}{#4}}%
      {\section@numsectionnonum@{#1}{#2}{#4}[#4]}}

\def\section@numsectionnonum@#1#2#3[#4]{%
   \section@section@{#2}{%
      \section@sectionbanner@{#2}{\@cs@{#2banneru}{#3}}%
      \@expandafter@{\@expandafter@{#1*{toc}{#2}}}%
         \csname section@\@cs@{section@tocchoice@#2}choice@\endcsname{#3}{#4}%
      \@expandafter@{\@expandafter@{\@cs@{#2mark}}}%
         \csname section@\@cs@{section@markchoice@#2}choice@\endcsname{#3}{#4}%
   }\ignorespaces}

\def\section@numsect@#1#2#3{\par
   \@ifnext@[%
      {\section@@numsect@{#1}{#2}{#3}}%
      {\section@@numsect@{#1}{#2}{#3}[#3]}}

\def\section@@numsect@#1#2#3[#4]{%
   \stepcounter{#2}%
   \def\currentcounter{#2}%
   \section@section@{#2}{%
      \section@sectionbanner@{#2}{\@cs@{#2banner}{#3}}%
      \@expandafter@{\@expandafter@{#1{toc}{#2}}}%
         \csname section@\@cs@{section@tocchoice@#2}choice@\endcsname
            {#3}{#4}{\@cs@{the#2}}%
      \@expandafter@{\@expandafter@{\@cs@{#2mark}}}%
         \csname section@\@cs@{section@markchoice@#2}choice@\endcsname{#3}{#4}%
   }\ignorespaces}

\DeclareOption{toc}
   {\usecarrot{toc}
    \let\newsection\section@newtocsection@}

\DeclareOption{number}
   {\usecarrot{counter}
    \let\section@newsection@\section@newnumberedsection@}

\def\newsection{\section@newsection@\section@notocentry@}

\def\section@newtocsection@{\relax
   \@ifnextchar@*
      {\expandafter\section@newsection@\expandafter\section@notocentry@\@eat@}
      {\section@newsection@\writecontentsentry}}

\def\section@notocentry@#1#2{\@eattwo@}

\def\section@section@#1#2{%
   \@cs@{section@prehook@#1}\relax
   \@cs@{section@preskip@#1}%
   #2\par
   \@cs@{section@posthook@#1}\relax
   \@cs@{section@postskip@#1}%
   \postsectionindent}

\def\postsectionindent{%
   \edef\@action@{\everypar={\hskip-\parindent\the\everypar
   \everypar={\the\everypar}}}\@action@}