% anonchap.sty
%
% Provides commands to make \chapter typeset like \section
% DO NOT USE WITH THE TOCBIBIND PACKAGE (which also supplies these commands)
%
% Usage of this package is described after the source code, below.
%
% Author: Peter Wilson, Herries Press
% Maintainer: Will Robertson (will dot robertson at latex-project dot org)
% Copyright 1996--2000 Peter Wilson
%
% Released under the LaTeX Project Public License, v1.3c or later.
% The current maintainer of this work is Will Robertson.
%
% CHANGE HISTORY
% v1.1a - New maintainer (Will Robertson)
% v1.2  - Add support for tagged PDF (copied from tocbibind)
%
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{anonchap}[2026/06/05 v1.2 typeset chapter like section]

\IfDocumentMetadataTF
  {
   \newcommand\simplechapter[1][]{%
         \IfInstanceExistsF{heading}{chapter-orig}{%
           \DeclareInstanceCopy{heading}{chapter-orig}{chapter}%
           \DeclareInstanceCopy{headformat}{chapter-orig}{chapter}%
         }%
         \EditInstance{heading}{chapter}{%
            prefix = #1
           ,headformat-instance=chapter
           ,prefix-decls=\Huge
           ,number-decls=\Huge
           ,number-format=\thechapter\simplechapterdelim
         }%
         \DeclareInstance{headformat}{chapter}{hang}{%
            number-title-sep=\WordSpaceAmount{1}%
           ,prefix-number-sep:e=\IfBlankTF{#1}{0pt}{\noexpand\WordSpaceAmount{1}}%
         }%
       }%
    \newcommand\restorechapter{%
      \IfInstanceExistsT{heading}{chapter-orig}{%
        \DeclareInstanceCopy{heading}{chapter}{chapter-orig}%
        \DeclareInstanceCopy{headformat}{chapter}{chapter-orig}%
      }%
    }%
 }
 {
   \newcommand{\simplechapter}[1][\@empty]{%
     \let\@tbiold@makechapterhead\@makechapterhead
     \renewcommand{\@makechapterhead}[1]{%
       \vspace*{50\p@}%
       {\parindent \z@ \raggedright
        \normalfont
        \interlinepenalty\@M
        \Huge\bfseries #1\space\thechapter\simplechapterdelim\space
           ##1\par\nobreak
        \vskip 40\p@
      }}
   }
   \newcommand{\restorechapter}{%
     \@ifundefined{@tbiold@makechapterhead}{}%
     {\let\@makechapterhead\@tbiold@makechapterhead}%
   }
 }

\newcommand{\simplechapterdelim}{}

\endinput

% Usage:
% \simplechapter[<name>] and \simplechapterdelim{<delim>} act together
% so that any subsequent \chapter commands, for example \chapter{First}
% ... \chapter{Second}...,
% will be typeset in the style of a \section (or numbered \chapter*) as:
% <name> 1<delim> First
% ...
% <name> 2<delim> Second
%
% A subsequent \restorechapter command will reset the \chapter typesetting
% back to its default style.
%
% Note that the argument to \simplechapter is optional, and that by default
% \simplechapterdelim is defined as \newcommand{\simplechapterdelim}{}.
%
% Extending the above example:
% \simplechapter
% \chapter{First}
% ...
% \renewcommand{\simplechapterdelim}{:}
% \chapter{Second}
% ...
% \restorechapter   % restore before issuing a modified \simplechapter
% \simplechapter[Chap]
% \chapter{Third}
% ...
% \restorechapter
% \chapter{Fourth}
% ...
% Will be typeset as:
% 1 First
% ...
% 2: Second
% ...
% Chap 3: Third
% ...
% Chapter 4
% Fourth
% ...
%