path: root/Master/texmf-dist/source/latex/halloweenmath/halloweenmath.dtx

% \iffalse
%   (This is a META-COMMENT.)
%
%   This is file `halloweenmath.dtx'.
%
%   This file is part of a work named "halloweenmath package".
%
%   Copyright (C) 2017 by Gustavo MEZZETTI.
%
%   This file may be distributed and/or modified under the conditions
%   of the LaTeX Project Public License, either version 1.3 of this
%   license or (at your option) any later version.
%   The latest version of this license is in
%     http://www.latex-project.org/lppl.txt
%   and version 1.3 or later is part of all distributions of LaTeX
%   version 2005/12/01 or later.
%
%   The halloweenmath package has the LPPL maintenance status
%     "author-maintained".
%
%   The file `manifest.txt' that comes along with this file specifies what the
%   halloweenmath package consists of; more precisely, it explains how the
%   locutions "Work" and "Compiled Work", used in the LaTeX Project Public
%   License, are to be interpreted in the case of this work.
%
%   Note that the distribution of this file alone is "distribution of
%   only part of the Work" in the sense of the LaTeX Project Public
%   License, and should be avoided (see the LaTeX Project Public
%   Licence for details).
%
%   (End of the META-COMMENT.)
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% \def\docdate {2017/01/06}
% \def\doclongdate{January~6, 2017}
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% \changes{0.01}{2017 Jan 06}{First writing of the code}
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% \newcommand*{\DS}{\textsf{DocStrip}}
% \newcommand*{\TikZ}{Ti\emph{k}Z}
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%
% \title{
%    The \packlass{\halloweenmath} package:\\
%    scary and creepy math symbols\\
%    with \texorpdfstring{\hologo{AmSLaTeX}}{AMS-LaTeX}\ 
%    integration\thanks{This file has
%    version~\fileversion, release date \filedate;
%    last documentation update: \docdate.
%    Copyright \copyright~2017 by G.~Mezzetti
%    (see page~\pageref{S:Copy}).}
% }
% \author{G. Mezzetti}
% \date{\doclongdate}
%
% \hypersetup{
%   pdftitle        = {The halloweenmath package:
%                       scary and creepy math symbols
%                       with AMS-LaTeX integration},
%   pdfauthor       = {G. Mezzetti},
%   pdfsubject      = {Documentation of the halloweenmath package},
%   pdfkeywords     = {Halloween, math, scary mathematical symbols},
%   pdfcreationdate = {D:20170106000000},
%   pdfmoddate      = {D:20170106000000},
%   bookmarksopen,
%   bookmarksopenlevel = 1
% }
%
% \pdfbookmark[0]{Front Matter}{FrontMatter}
% \maketitle
%
% \begin{abstract}
%    This document describes a \LaTeX\ package that originates from a question
%    asked for enjoyment on
%    \href{http://tex.stackexchange.com/}{\emph{\TeX\,-\,\LaTeX\ Stack
%    Exchange}} (see~\cite{bib:cfr}) by the user
%    \href{http://tex.stackexchange.com/users/39222/cfr}{\cfr}; this package
%    defines a handful of commands for typesetting mathematical symbols of
%    various kinds (including ``large'' operators, extensible arrow-like
%    relations, and growing arrow-like math accents) that all draw from the
%    classic Halloween-related iconography (pumpkins, witches, ghosts, cats, and
%    so on) while being, at the same time, seamlessly integrated within the rest
%    of the mathematics produced by \hologo{LaTeX}\slash\hologo{AmSLaTeX}.
% \end{abstract}
%
% \vfil
%
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%     ^^A
%     ^^A The cat:
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%
% \newpage
% \tableofcontents
% \listoffigures
%
% \newpage
% \begingroup
%
%    \setlength{\parskip}{\medskipamount}
%    \setlength{\parindent}{0pt}
%
% \section*{Copyright notice}
%    \label{S:Copy}
%    \vspace{-\parskip}
%
%    Copyright \copyright~2017 by Gustavo \textsc{Mezzetti}.
%    All rights are reserved, except as noted below.
%
%    This document has been produced by feeding to a \LaTeX\ typesetting engine
%    the file \filedir{\filename} version \fileversion\ (\docdate).  This file
%    is part of a work named ``\packlass{\halloweenmath} package'', and may be
%    distributed and/or modified only as a part thereof.
%    Subsection~\ref{sS:License} on page~\pageref{sS:License} explains the
%    conditions under which the \packlass{\halloweenmath} package may be
%    distributed and/or modified.
%
%    The \packlass{\halloweenmath} package has the following LPPL maintenance 
%    status:\\
%    ``author-maintained''.
%
%    Permission is granted to make new printed copies of this document, by any
%    means (\emph{e.g.}, photocopying, direct printing from the electronic
%    version, and so on).
%
%    Note, though, that distribution of this document alone is ``distribution of
%    only part of the Work'' in the sense of the \LaTeX\ Project Public License,
%    and should therefore be avoided: please distribute, in addition, the source
%    file \filedir{\halloweenmath.dtx} together with all other files listed in
%    \filedir{manifest.txt}, as explained as well in Subsection~\ref{sS:License}
%    and in the file \filedir{manifest.txt} itself.
%
% \section*{Author's addresses}
% \label{S:MyAddresses}
%    \vspace{-\parskip}
%
%    The recommended way to contact the author is by e-mail; his address is:
%
%    \begin{list}{\setlength{\topsep}{0pt}}\item\relax
%      gustavo dot mezzetti at istruzione dot it
%    \end{list}
%
%    Please include the \emph{exact} phrase \verb*|halloweenmath package| in the
%    \emph{subject} of your message; otherwise, your message could be
%    thrown away by a mail filter.  In this regard, the weakness of the
%    laws concerning the protection of privacy forces me to explicitly
%    forbid the use of the above address for any kind of advertising,
%    marketing, polling, or similar commercial or statistical contact.
%
%    If you have no e-mail access, write to:
%
%    \begin{list}{\setlength{\topsep}{0pt}}\item\relax
%      Gustavo \textsc{Mezzetti}\\
%      L.~S.~U. ``A.~di Savoia Duca degli Abruzzi''\\
%      Via del Santo, 57\\
%      I--35123\quad PADOVA\quad PD\\
%      Italy
%    \end{list}
%
% \endgroup
%
%
%
% \setcounter{secnumdepth}{0}
%
%
%
% \clearpage
% \section{Introduction}
%
%    On October~31, 2016, around 3 in the morning (GMT\@), user
%    \href{http://tex.stackexchange.com/users/39222/cfr}{\cfr} asked a
%    question~\cite{bib:cfr} on the
%    \href{http://tex.stackexchange.com/}{\emph{\TeX\,-\,\LaTeX\ Stack Exchange}
%    network}, challenging other users to contribute \LaTeX\ documents that
%    showcased ``the spookiest, creepiest images'' ever possible.  I~was aware
%    of a method---well known, nonetheless---to integrate arbitrary pictures
%    into math formulas as though they were mathematical symbols, so, on the
%    pretext ``that, since \hologo{(La)TeX} is a language primarily designed to
%    handle text with math, the lack of a `math-flavored'
%    answer~\ldots\linebreak[0]\,was a gap that ought to be filled'', I~wrote an
%    answer implementing a command that drew a (not particularly spooky or
%    creepy) little witch astride of her broom, but with the silly distinctive
%    feature of being seen by \LaTeX\ as a mathematical ``large'' operator like
%    "\sum", "\prod", "\int", or "\bigcup"; this first command was named
%    "\mathwitch" and was ``intended for denoting the operation of applying
%    black magic to the ensuing subformula''.
%
%    I~subsequently added an extensible math accent similar to
%    "\overrightarrow", but with the arrow replaced by a broom carrying the same
%    witch and a black cat, and my answer ended up winning the contest (the
%    presence of the cat turned out to be a decisive factor); besides, some
%    users were so enthusiast of the new commands that they requested that they
%    were re-implemented as a new, stand-alone package.  And here it is.
%
%    In the writing of the package, more features, and creatures, have been
%    added.  Also available now are:
%    \begin{itemize}
%    \item
%    ghosts, both still and hovering (or, if you prefer, acting both as ordinary
%    symbols and as math accents similar to "\overrightarrow");
%    \item
%    a "\pumpkin" binary operator, with an associated ``large'' operator named
%    "\bigpumpkin"\footnote{\cs{greatpumpkin} is available as a synonym, in
%    homage to Linus van Pelt.} (cf.~"\cup" vs.\ "\bigcup", "\cap" vs.\
%    "\bigcap", "\vee" vs.\ "\bigvee", "\oplus" vs.\ "\bigoplus",\,\ldots);
%    \item
%    extensible ``arrow-like'' brooms that act as relation symbols;
%    \item
%    clouds, for denoting unscrutable subformulas (this one is even sensible!);
%    \item
%    and still more.
%    \end{itemize}
%    All the above are available for the \texttt{bold} math version as well as 
%    for the \texttt{normal} one.
%    The symbols provided should prove sufficient for preparing lecture notes,
%    slides, tests, or even exams to amuse~(?\@) your students with during the
%    Halloween period.  Of course, any suggestion for additions and/or
%    improvements are most welcome: you can find my addresses on
%    page~\pageref{S:MyAddresses}.
%
%    As for the name of this new package, \cfr\ initially
%    \href{http://tex.stackexchange.com/questions/336768/seasonal-challenge-contributions-from-texing-dead-welcome#comment828307_337719}{proposed}
%    \packlass{mathwitch} (from the name of the main command);
%    \href{http://tex.stackexchange.com/users/81905/guilherme-zanotelli}{\TeXSXuser{Guilherme
%    Zanotelli}} then
%    \href{http://tex.stackexchange.com/questions/336768/seasonal-challenge-contributions-from-texing-dead-welcome#comment828796_337719}{suggested}
%    \packlass{mathemagics} (a truly befitting pun!); but in the end I~decided
%    to choose \packlass{\halloweenmath} because (1)~it instantly and clearly
%    communicates the context in which the package arose, as well as the purpose
%    for which it was written, and (2)~it is 13~characters long.
%
%    This work is dedicated to \cfr, without whom it would have never seen the
%    light, and to whom I~am offering it ``as an Epiphany present''---or rather,
%    as one would say in Italian, ``\emph{come regalo per la Befana}'', where
%    the last word bears not-so-subtle connections with the world of
%    witches\ldots
%
%    \subsection{Disclaimer}
%
%    Although a \LaTeX\ package is a piece of software that executes in a
%    rather protected environment and should therefore be relatively
%    incapable of doing serious damages, no warranty is given, as usual with
%    computer software, that this code will work properly, or even that it
%    will work at all.  To be on the safe side, be aware that using this
%    code can even result in loss of data and/or damages to your disks and
%    your storage media.  If you use this code, you do so exclusively at
%    your own risk!
%
%    See Subsection~\ref{sS:License} and the \LaTeX\ Project Public
%    Licence for more information.
%
%    \subsection{About this document}
%
%    This document, like many documentation files distributed for \LaTeX, is
%    divided into two parts.
%
%    The first part, \emph{User's Manual}, contains all the documentation you
%    need to be able to \emph{use} the \packlass{\halloweenmath} package.  Every
%    user of this package will probably want to read this part.
%
%    The second part, \emph{Implementation}, can be omitted if you
%    want (explanations on how to omit it are given at the beginning
%    of the part itself), and contains information that concerns only
%    ``hackers'' who want to learn how the package that this document
%    presents is \emph{implemented}.  Actually, this part contains the
%    complete listing of the \LaTeX\ code that implements the macros,
%    in the usual \DS\ format; if you are not a \LaTeX\ hacker, this
%    part will probably have little meaning to you.
%
%    As I~said above, this package is an Epiphany gift for \TeXSXuser{cfr}, and,
%    for this reason, I~want to submit it to CTAN\@ on January~6, 2017.
%    Regrettably, I~couldn't write most of the comments in the
%    \emph{Implemenation} part in time for the submission, which, on the other
%    hand, I~don't want to defer to a later date for any reason whatsoever.
%    Some sparse comments, nonetheless, are sprinkled throughout the code at
%    certain key places, and I~hope they will suffice to understand what's going
%    on.  I~apologize for submitting this work in an incomplete form;
%    unfortunately, at present I~cannot even foresee when I'll be able to finish
%    it.
%
%
%
% \setcounter{secnumdepth}{3}
%
%
%
% \clearpage
% \part{User's Manual}
%
% \section{About this part}
%
%    This part tells you how to use the \packlass{\halloweenmath} package.  It
%    also contains detailed instructions on how to install it and how to
%    generate this same documentation, but normally you need not bother reading
%    this information, either because your \TeX\ distribution already includes
%    both the package code and its documentation, or because package
%    installation is implicitly dealt with by the automatic update mechanism
%    provided by the distribution itself.
%
% \section{How to use the \packlass{\halloweenmath} package}
% \label{S:Usage}
%
%    This section explains everything you need to know in order to be able to
%    use the \packlass{\halloweenmath} package.  However, to keep this document
%    independent of the package itself, the output produced by the various
%    commands is not shown here: for this, you are referred to \cite{bib:manual}
%    and to~\cite{bib:sample}.
%
%    \subsection{Package loading}
%
%    The usual "\usepackage" declaration is used, as in
%    \begin{verbatim}\usepackage{halloweenmath}\end{verbatim} It should be
%    noted, however, that the \packlass{\halloweenmath} package requires the
%    \packlass{\amsmath} package, and loads it (without specifying any option)
%    if it is not already loaded.  If you want to pass options to
%    \packlass{\amsmath}, load it before \packlass{\halloweenmath}.
%
%    The \packlass{\halloweenmath} package defines no options by itself;
%    nevertheless, it does honor the [\opt{no}]\opt{sumlimits} options from the
%    \packlass{\amsmath} package (see below).
%
%    \subsection{Scary symbols}
%
%    This package defines some commands \emph{for use in mathematical mode},
%    which provide a handful of symbols, all of which honor the \texttt{bold}
%    math version, when in force.  They can be loosely grouped as follows.
%
%    \subsubsection{Pumpkins}
%
%    \DescribeMacro{\pumpkin}
%    \DescribeMacro{\bigpumpkin}
%    \DescribeMacro{\greatpumpkin}
%    It is even too obvious to begin with pumpinks.  In this regard, the package
%    provides two interrelated commands:
%    \begin{itemize}
%    \item
%    "\pumpkin" yields a binary operator symbol in the shape of a (little) 
%    pumpkin;
%    \item
%    "\bigpumpkin" is the ``large'' operator that is to "\pumpkin" as
%    "\bigoplus" is to "\oplus"; it typesets a somewhat bigger pumpkin in
%    in-line formulas, which becomes significantly larger in displayed formulas.
%    \end{itemize}
%    The [\opt{no}]\opt{sumlimits} options from the \packlass{\amsmath} package
%    also affect the "\bigpumpkin" command.  As a homage to Linus van Pelt,
%    "\greatpumpkin" is available as a perfect synonym for "\bigpumpkin".
%
%    \subsubsection{Witches, brooms, and black cats}
%
%    All this arose from a witch.
%
%    \DescribeMacro{\mathwitch} \DescribeMacro{\reversemathwich}
%    The "\mathwitch" command yields a ``large'' operator symbol, similar to
%    "\sum", representing a witch astride of a broom (in my answers
%    to~\cite{bib:cfr}, I~claimed that this symbol denotes the operation of
%    applying black magic to the ensuing subformula, a fundamental operation in
%    so many mathematical proofs\ldots).  There is also a "\reversemathwich"
%    command, which produces an operator that looks like a mirror image of the
%    above, for denoting the inverse operation of undoing the black magic.  Both
%    commands honor the [\opt{no}]\opt{sumlimits} options from the
%    \packlass{\amsmath} package.
%
%    \DescribeMacro{\xrightwitchonbroom}
%    \DescribeMacro{\xleftwitchonbroom}
%    Witches infest the field of extensible ``arrow-like'' symbols too: the
%    commands "\xrightwitchonbroom" and "\xleftwitchonbroom" are syntactically
%    identical to, \emph{e.g.}, "\xrightarrow", but produce an extensible broom
%    with a witch sitting on it.  That is to say, the syntax for
%    "\xrightwitchonbroom" is as follows
%    \begin{flushleft}
%      \cmd{\xrightwitchonbroom}\oarg{under text}\marg{over text}
%    \end{flushleft}
%    and "\xleftwitchonbroom" is similar.
%
%    \DescribeMacro{\overrightwitchonbroom}
%    \DescribeMacro{\overleftwitchonbroom}
%    \DescribeMacro{\underrightwitchonbroom}
%    \DescribeMacro{\underleftwitchonbroom}
%    Finally, the four commands
%    \begin{flushleft}
%      "\overrightwitchonbroom "\marg{subformula} \\
%      "\overleftwitchonbroom  "\marg{subformula} \\
%      "\underrightwitchonbroom"\marg{subformula} \\
%      "\underleftwitchonbroom "\marg{subformula}
%    \end{flushleft}
%    are similar to, \emph{e.g.}, "\overrightarrow", and typeset a broom, with a
%    witch sitting on it, over or under the subformula specified in their
%    argument.\footnote{It should be noted that, in my answers
%    to~\cite{bib:cfr}, only the command that now corresponds to
%    \cmd{\overrightwitchonbroom} was provided, but under the different name
%    \cmd{\overrightbroom}.}
%
%    \paragraph*{Important note:}
%    All the commands described in this subsection have a \mbox{$*$-form} that
%    adds a black cat on the broomstick.  The syntax should be easy to remember,
%    since the additional asterisk can be thought of as reminiscent of the cat.
%
%    \subsubsection{Ghosts}
%
%    Of course, on Hallowen, ghosts cannot be missing either.
%
%    \DescribeMacro{\mathghost}
%    \DescribeMacro{\mathrightghost}
%    \DescribeMacro{\mathleftghost}
%    There are three similar commands (without arguments) that produce ordinary
%    symbols, that is, symbols that are treated like letters: the "\mathghost"
%    command yield a symbol resembling a ghost standing upfront; the
%    "\mathrightghost" (resp., "\mathleftghost") command gives a symbol that
%    looks like a ghost moving toward the right (resp., the left).
%
%    \DescribeMacro{\xrightswishingghost}
%    \DescribeMacro{\xleftswishingghost}
%    Once again, ghosts too haunt the region of extensible ``arrow-like''
%    symbols:
%    \begin{flushleft}
%      "\xrightswishingghost"\oarg{under text}\marg{over text} \\
%      "\xleftswishingghost "\oarg{under text}\marg{over text}
%    \end{flushleft}
%    are analogous to, \emph{e.g.}, "\xrightarrow", but, in place of the arrow,
%    draw a ghost swishing, respectively, toward the right and toward the left.
%
%    \DescribeMacro{\overrightswishingghost}
%    \DescribeMacro{\overleftswishingghost}
%    \DescribeMacro{\underrightswishingghost}
%    \DescribeMacro{\underleftswishingghost}
%    It is now easy to guess what the following four commands do:
%    \begin{flushleft}
%      "\overrightswishingghost "\marg{subformula} \\
%      "\overleftswishingghost  "\marg{subformula} \\
%      "\underrightswishingghost"\marg{subformula} \\
%      "\underleftswishingghost "\marg{subformula}
%    \end{flushleft}
%
%    \subsubsection{Other symbols}
%
%    The \packlass{\halloweenmath} package implements one more symbol that could
%    loosely be connected with the world of witches.
%
%    \DescribeMacro{\mathcloud} \DescribeMacro{\reversemathcloud}
%    Mathemagicians often deal with unscrutable formulas.  To represent them,
%    the "\mathcloud" command (without arguments) is available, which produces a
%    symbol, with the form of a cloud, that behaves to a certain extent like a
%    fraction, in that it is typeset in a significantly larger size in displayed
%    formulas than in in-line ones.  The companion command "\reversemathcloud"
%    yields a mirror image of the same symbol.
%
%    \subsection{Script-style version of standard over\protect\slash under
%      arrows}
%
%    In order to implement our over\slash under ``arrow-like'' symbols, we had
%    to develop an extension of some internal macros of the \packlass{\amsmath}
%    package.  These extensions can be applied to produce variants of the
%    standard over\slash under arrows too.
%
%    \DescribeMacro{\overscriptrightarrow}
%    \DescribeMacro{\overscriptleftarrow}
%    \DescribeMacro{\overscriptleftrightarrow}
%    \DescribeMacro{\underscriptrightarrow}
%    \DescribeMacro{\underscriptleftarrow}
%    \DescribeMacro{\underscriptleftrightarrow}
%    The following six commands are analogous to their standard counterparts
%    whose names do not contain the "script" substring, but the arrows they put
%    above or below the given subformulas are typeset in their relative script
%    style, instead of in the same style as the subformulas themselves (as the
%    standard commands do):
%    \begin{flushleft}
%      "\overscriptrightarrow     "\marg{subformula} \\
%      "\overscriptleftarrow      "\marg{subformula} \\
%      "\overscriptleftrightarrow "\marg{subformula} \\
%      "\underscriptrightarrow    "\marg{subformula} \\
%      "\underscriptleftarrow     "\marg{subformula} \\
%      "\underscriptleftrightarrow"\marg{subformula}
%    \end{flushleft}
%
% \section{Installing the \packlass{\halloweenmath} package and generating this manual}
%
%    As usual for \LaTeX\ distributions, the \packlass{\halloweenmath}
%    package is distributed in the form of a \filedir{.dtx} file,
%    namely \filedir{\halloweenmath.dtx}, and an accompanying
%    \filedir{.ins} file, namely \filedir{\halloweenmath.ins}.
%
%    \subsection{Installation}
%
%    To extract the code, run \LaTeX\ (or plain \TeX) once on the
%    file \filedir{\halloweenmath.ins}.  This will generate the following
%    \LaTeX\ input file:
%    \begin{quote}
%      \ttfamily
%      \halloweenmath.sty
%    \end{quote}
%    To finish the installation, move it to a \LaTeX\ input directory.  The
%    above listing of the files you need to move is also displayed on the
%    terminal at the end of the run of the file \filedir{\halloweenmath.ins}.
%    The documentation of your \TeX\ installation should tell you how to find
%    the \LaTeX\ input directory/ies, and probably also how to create new
%    \LaTeX\ input directories reserved to contain your private classes and
%    packages.
%
%    The \emph{proposed} TDS-compliant directory where the above file should be
%    put is
%    \begin{quote}
%      \texttt{\$TEXMF/tex/latex/halloweenmath/}
%    \end{quote}
%
%    Please note that before using the \packlass{\halloweenmath} package
%    you must read its license (see Subsection~\ref{sS:License}) to
%    see whether its terms are acceptable for you, especially for what
%    concerns the lack of any warranty; if they are not, don't use
%    this program.
%
%    \subsection{Documentation}
%
%    To produce this documentation, run \LaTeX\ three times (for the
%    table of contents to be correct) on the file
%    \filedir{\halloweenmath.dtx}.  This won't produce the index and the
%    change history, however: for those, you have to run
%    \emph{MakeIndex} on the files \filedir{\halloweenmath.idx} and
%    \filedir{\halloweenmath.glo}, produced during the last of the
%    aforesaid three \LaTeX\ runs, with the styles \filedir{gind.ist}
%    and \filedir{gglo.ist}, respectively (these styles are part of
%    the standard \LaTeX\ distribution); then pass
%    \filedir{\halloweenmath.dtx} through \LaTeX\ twice more.
%
%    The documentation produced by default includes the
%    \emph{Implementation} part too; see the beginning of this part
%    for instructions on how to omit it.
%
%    \subsection{License}
%    \label{sS:License}
%
%    The \packlass{\halloweenmath} package is \emph{not} in the public
%    domain: its author, Gustavo \textsc{Mezzetti}, owns the
%    copyright, and in general retains all the rights therein; but as
%    a special exception, the author grants you the permissions
%    indicated below.
%
%    \subsubsection{Distribution and/or modification}
%
%    The \packlass{\halloweenmath} package may be distributed and/or
%    modified under the conditions of the \LaTeX\ Project Public
%    License, either version~1.3 of this license or (at your option)
%    any later version.  The latest version of this license is in
%    \begin{quote}
%      \ttfamily
%      http://www.latex-project.org/lppl.txt
%    \end{quote}
%    and version~1.3 or later is part of all distributions of \LaTeX\
%    version 2005/12/01 or later.
%
%    The \packlass{\halloweenmath} package has the LPPL maintenance status
%    ``author-maintained''.
%
%    The file \filedir{manifest.txt} included along with this file
%    specifies what the \packlass{\halloweenmath} package consists of; more
%    precisely, it explains how the locutions ``Work'' and ``Compiled
%    Work'', used in the \LaTeX\ Project Public License, are to be
%    interpreted in the case of this work.
%
%    \subsubsection{Use}
%
%    The use of the \packlass{\halloweenmath} package is unrestricted,
%    provided that you accept the terms and conditions of the \LaTeX\
%    Project Public License and of the following subsection for what
%    concerns the absence of any warranty.
%
%    \subsubsection{No warranty}
%
%    There is absolutely no warranty for the \packlass{\halloweenmath}
%    package.  The Copyright Holder provides the \packlass{\halloweenmath}
%    package ``as is'', without warranty of any kind, either expressed
%    or implied, including, but not limited to, the implied warranties
%    of merchantability and fitness for a particular purpose.  The
%    entire risk as to the quality and performance of the
%    \packlass{\halloweenmath} package is with you.  Should the
%    \packlass{\halloweenmath} package prove defective, you assume the cost
%    of all necessary servicing, repair, or correction.
%
%    In no event will The Copyright Holder, or any other party who may
%    distribute and/or modify the \packlass{\halloweenmath} package as
%    permitted by the \LaTeX\ Project Public License, be liable to you
%    for damages, including any general, special, incidental or
%    consequential damages arising out of any use of the
%    \packlass{\halloweenmath} package or out of inability to use it
%    (including, but not limited to, loss of data, data being rendered
%    inaccurate, or losses sustained by anyone as a result of any
%    failure of the \packlass{\halloweenmath} package to operate with any
%    other programs), even if The Copyright Holder or said other party
%    has been advised of the possibility of such damages.
%
% \StopEventually{
%    \setcounter{secnumdepth}{0}
%    \providecommand*\bysame{\leavevmode\hbox to3em{\hrulefill}\thinspace}
%
%    \clearpage
%    \pdfbookmark[0]{Back Matter}{BackMatter}
%    \begin{thebibliography}{9}
%    \addcontentsline{toc}{section}{\refname}
%
%    \bibitem{bib:cfr}
%      \emph{Seasonal Challenge (Contributions from \TeX ing Dead 
%        Welcome)},\\
%      \url{http://tex.stackexchange.com/q/336768/69818}
%
%    \bibitem{bib:manual}
%      \emph{A short manual for the \packlass{\halloweenmath} package},
%      in preparatiom.
%
%    \bibitem{bib:sample}
%      \emph{A sample article that uses the \packlass{\halloweenmath} package},
%      in preparation.
%
%    \end{thebibliography}
% }
%
%
%
% \clearpage
% \part{Implementation}
%
% \section{About this part}
%
%    This part is of interest only to \LaTeX\ hackers; to avoid
%    having this part printed, look in the file \filedir{\filename}
%    for a line that looks \emph{exactly} like this
%    \begin{verbatim}%% \OnlyDescription % uncomment to discard Implementation part\end{verbatim}
%    and remove the two leading percent signs ("%%").
%
% \section{A driver for this document}
%
%    This part of the file is \emph{not} included in any generated file:
%    it is simply the driver.
%    \begin{macrocode}
%<*driver>
%    \end{macrocode}
%
%    To begin with, we load the \packlass{ltxdoc} class
%    and the packages we require.
%    \begin{macrocode}
\documentclass{ltxdoc}
\usepackage{color,pict2e,hologo}
\usepackage{hypdoc}
%    \end{macrocode}
%    We now set a few typesetting options.
%    First of all, we want a history listing and a full index, the latter
%    organized by line numbers.
%    \begin{macrocode}
\RecordChanges
\EnableCrossrefs
\CodelineIndex
%    \end{macrocode}
%    If you don't want to include the second part of this document,
%    \emph{Implementation}, uncomment the line containing the command
%    "\OnlyDescription".
%    \begin{macrocode}
%% \OnlyDescription % uncomment to discard Implementation part
%    \end{macrocode}
%    Finally, setting "\hfuzz" and "\vfuzz" to 0~points is only one
%    of the many neurotic symptoms of the author!
%    \begin{macrocode}
\hfuzz = 0pt
\vfuzz = 0pt
%    \end{macrocode}
%    Now input this same file, using \DS\ conventions.
%    \begin{macrocode}
\begin{document}
  \DocInput{halloweenmath.dtx}
%    \end{macrocode}
%    Then print the change list and the index.  We put these commands in
%    the driver, rather than in the comments of this file, because
%    producing the change list and the index is somewhat cumbersome, and some
%    users could prefer to omit them: such users should simply use a
%    different driver.
%    \begin{macrocode}
  % \clearpage % attach Change history below References
  \PrintChanges
  \clearpage \PrintIndex
%    \end{macrocode}
%    When this file is read directly by \LaTeX\ without the intervention
%    of \DS, the following line will make \TeX\ stop
%    reading.
%    \begin{macrocode}
\end{document}
%    \end{macrocode}
%    End of driver module.
%    \begin{macrocode}
%</driver>
%    \end{macrocode}
%
% \section{The code for the \packlass{\halloweenmath} package}
%
%    This part of the file goes into \filedir{\halloweenmath.sty}.
%    \begin{macrocode}
%<*halloweenmath>
%    \end{macrocode}
%
%    \subsection{Identification}
%
%    No particular reason for asking for a particular release of \LaTeXe; but at
%    least, let us specify a date on which the \packlass{\picttwoe} package was
%    likely to exist.
%    \begin{macrocode}
\NeedsTeXFormat{LaTeX2e}[2004/06/01] % LaTeX2e is required!
%    \end{macrocode}
%    The usual identification:
%    \begin{macrocode}
\ProvidesPackage{halloweenmath}
                [2017/01/06 v0.01 (development)]
%    \end{macrocode}
%
%    \subsection{Initial code}
%
%    This segment is empty in the \packlass{\halloweenmath} package.
%
%    \subsection{Declaration of options}
%
%    This segment is empty in the \packlass{\halloweenmath} package.
%
%    \subsection{Option processing}
%
%    This segment is empty in the \packlass{\halloweenmath} package.
%
%    \subsection{Package loading}
%
%    Besides the \packlass{\picttwoe} package, that we need to draw the 
%    pictures, we also require the \packlass{\amsmath} package.
%    \begin{macrocode}
\RequirePackage{amsmath,pict2e}
%    \end{macrocode}
%
%    \subsection{Main code}
%
%    Let's begin with an important remark.  It would be pretty easy to fulfill 
%    the purpose of this package using \TikZ; this has been deliberately 
%    avoided.  This package has been written for fun, and part of this fun lay 
%    in the constraint of using only the means provided by the \env{picture} 
%    environment, albeit with the \packlass{\picttwoe} extensions.  Please 
%    accept this fact without arguing about it.
%
%    The names of all the macros defined in this package start with the prefix 
%    "\@HwM@" (``namespace'' prefix).
%
%    \subsubsection{Preliminary macros}
%
%    We begin with defining some macros that provide basic functionality.
%
%    \begin{macro}{\@HwM@tempa}
%    Temporary scratch macro reserved for this package.  Here we just check 
%    that the name can be used, while, at the same time, reserving it.
%    \begin{macrocode}
\@ifdefinable\@HwM@tempa{}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@thickness@units@for}
%    The unit of measure we are going to use for line thicknesses; since it is
%    defined in term of the ``default-rule-thickness'' "\fontdimen", it will
%    automatically scale with the font size.  The suffix "for" at the end of the
%    names reminds that a font selector like "\textfont" must follow and will be
%    absorbed as argument~\#1.
%    \begin{macrocode}
\newcommand*\@HwM@thickness@units@for[1]{\fontdimen 8 #1\thr@@}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@right@or@left}
%    Used to pass information about the orientation of left\slash right
%    symmetric figures.  Here we just check that the name can be used, at the
%    same time reserving it.
%    \begin{macrocode}
\@ifdefinable\@HwM@right@or@left{}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@set@right@dir}
%    Causes that the following left\slash right symmetric figure to face to the
%    right.
%    \begin{macrocode}
\newcommand*\@HwM@set@right@dir{%
  \let \@HwM@right@or@left \@firstoftwo
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@set@left@dir}
%    Causes that the following left\slash right symmetric figure to face to the
%    left.
%    \begin{macrocode}
\newcommand*\@HwM@set@left@dir{%
  \let \@HwM@right@or@left \@secondoftwo
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{environment}{@HwM@math@picture}
%    Customized \env{picture} environment for our ``math pictures'', makes some
%    initializations that are always needed (local to its group).  Arguments:
%    \begin{paramlist}
%      \param{1}
%        bounding box height, in coordinate units;\\
%      \param{2}
%        $y$-coordinate of lower left corner of bounding box;\\
%      \param{3}
%        additional code to be executed during initialization;\\
%      \param{4}
%        font selector (\emph{e.g.}, "\textfont");\\
%      \param{5}
%        bounding box width, in coordinate units;\\
%      \param{6}
%        $x$-coordinate of lower left corner of bounding box.
%    \end{paramlist}
%    \begin{macrocode}
\newenvironment*{@HwM@math@picture}[6]{%
  \setlength\unitlength{\fontdimen 22 #4\tw@}%
  #3%
  \@HwM@right@or@left{%
    \def\+{+}%
    \def\-{-}%
  }{%
    \def\+{-}%
    \def\-{+}%
  }%
  \picture(#5,#1)(#6,#2)%
}{\endpicture}
%    \end{macrocode}
%    \end{environment}
%
%    \begin{macro}{\@HwM@short@circuited@vphant}
%    ``Short-circuited'' version of "\vphantom".
%    \begin{macrocode}
\newcommand*\@HwM@short@circuited@vphant{\v@true\h@false\mathph@nt}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@oplus@strut}
%    Vertical phantom the size of "\oplus".  Arguments:
%    \begin{paramlist}
%      \param{1}
%        style selector (\emph{e.g.}, "\displaystyle").
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@oplus@strut[1]{%
  \@HwM@short@circuited@vphant #1\bigoplus@
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@d@pict@strut}
%    Inserts a ``depth-only half-strut'' (the~"d" in the name is for ``depth''),
%    \#1~is its size in picture units.
%    \begin{macrocode}
\newcommand*\@HwM@d@pict@strut[1]{%
  \vrule \@width\z@ \@height\z@ \@depth #1\unitlength
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@large@picture}
%    \begin{macro}{\end@HwM@large@picture}
%    This is actually a definition of an environment.  The environment beign
%    defined, namely \env{@HwM@large@picture}, is simply syntactic sugar for a
%    typical invocation of the \env{@HwM@math@picture} environment, for a
%    picture of ``large'' size (\( \mbox{height}=5 \), \( \mbox{depth}=3 \),
%    with the baseline running at \( y=-1 \)), suitable for the display-style
%    version of a large operator.  Supplies arguments \#1--\#4 of
%    \env{@HwM@math@picture}, with \#4 being "\textfont"; the caller must supply
%    the remaining ones.
%    \begin{macrocode}
\newcommand*\@HwM@large@picture{%
  \@HwM@math@picture{5}{-1}{\@HwM@d@pict@strut\thr@@}\textfont
}
\let\end@HwM@large@picture = \end@HwM@math@picture
%    \end{macrocode}
%    \end{macro}
%    \end{macro}
%
%    \begin{macro}{\@HwM@small@picture}
%    \begin{macro}{\end@HwM@small@picture}
%    This is actually a definition of an environment.  The environment beign
%    defined, namely \env{@HwM@small@picture}, is simply syntactic sugar for a
%    typical invocation of the \env{@HwM@math@picture} environment, for a
%    picture of ``small'' size (\( \mbox{height}=3 \), \( \mbox{depth}=1 \),
%    with the baseline running at \( y=-1 \)), suitable for the
%    non-display-style version of a large operator.  Supplies arguments \#1--\#3
%    of \env{@HwM@math@picture}; the caller must supply the remaining ones,
%    \emph{including} argument~\#4.
%    \begin{macrocode}
\newcommand*\@HwM@small@picture{%
  \@HwM@math@picture{3}{-1}{\@HwM@d@pict@strut\@ne}%
}
\let\end@HwM@small@picture = \end@HwM@math@picture
%    \end{macrocode}
%    \end{macro}
%    \end{macro}
%
%    \begin{macro}{\@HwM@oplus@picture}
%    \begin{macro}{\end@HwM@oplus@picture}
%    This is actually a definition of an environment.  The environment beign
%    defined, namely \env{@HwM@oplus@picture}, is simply syntactic sugar for a
%    typical invocation of the \env{@HwM@math@picture} environment, for a
%    picture having the vertical size of an "\oplus", with baseline running at
%    \( y=-1 \).  Supplies arguments \#1--\#3 of \env{@HwM@math@picture}; the
%    caller must supply the others, \emph{including} argument~\#4.
%    \begin{macrocode}
\newcommand*\@HwM@oplus@picture[1]{%
  \@HwM@math@picture{0}{-1}{\@HwM@oplus@strut #1}%
}
\let\end@HwM@oplus@picture = \end@HwM@math@picture
%    \end{macrocode}
%    \end{macro}
%    \end{macro}
%
%    \begin{macro}{\if@HwM@cat@}
%    Switch that tells whether a witch that is about to be drawn should be 
%    accompanied by her cat or not.
%    \begin{macrocode}
\@ifdefinable\if@HwM@cat@{\newif\if@HwM@cat@}
%    \end{macrocode}
%    \end{macro}
%
%    The following two macros should probably be unified (but is this
%    feasible?\@), since the first one isn't used elsewhere in the code.
%
%    \begin{macro}{\@HwM@if@bold@math}
%    \LaTeX-style conditional: if the math version is currently \texttt{bold},
%    executes the code in the first argument, otherwise the code in the second
%    argument.
%    \begin{macrocode}
\newcommand*\@HwM@if@bold@math{%
  \def\@tempa{bold}%
  \ifx\math@version\@tempa
    \expandafter\@firstoftwo
  \else
    \expandafter\@secondoftwo
  \fi
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@choose@thicknesses}
%    Shuffles arguments according to the current math version.
%    \begin{macrocode}
\newcommand*\@HwM@choose@thicknesses[3]{%
  \@HwM@if@bold@math{#1#3}{#1#2}
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@magic@star}
%    Draws a star; argument~\#1 is a scale factor.
%    \begin{macrocode}
\newcommand*{\@HwM@magic@star}[1]{%
  \begingroup
    \setlength\unitlength{#1\unitlength}%
    \picture(0,0)%
      \polygon*(0,1)(-.225,.309)(-.951,.309)(-.363,-.118)(-.588,-.809)%
              (0,-.382)(.588,-.809)(.363,-.118)(.951,.309)(.225,.309)%
    \endpicture
  \endgroup
}
%    \end{macrocode}
%    \end{macro}
%
%    \paragraph*{General remark:}
%    In all of the following drawings, the thickness of most of the lines
%    depends on the current math style.  On the other hand, some pictures are
%    made up of smaller reusable pieces that are shared among more than one
%    drawing.  As a matter of mental order, I~prefer to confine the lookup for
%    the current style to a single place for each picture, and pass the
%    appropriate thicknesses down to the macros that draw the single pieces as
%    parameters.  Nonetheless, the interface toward the rest of the code
%    requires macros that can draw a picture without requiring the caller to
%    specify thickness arguments.  This means that some drawing macros must
%    exist in two variants:
%    \begin{itemize}
%      \item
%        a ``private'' variant that requires the caller to specify thickness 
%        parameters;
%      \item
%        a ``public'' variant that doesn't require such parameters, but uses,
%        instead, the "\@HwM@choose@thicknesses" macro to find out the
%        appropriate thickness values by itself.
%    \end{itemize}
%    To make it clear when two macros are actually two such variants of the same
%    conceptual function, we shall consistently adhere to the following naming
%    convention:
%    \begin{itemize}
%      \item
%        the name of the``private'' private variant will be made up of words
%        separated by "@"~characters, and each of those word will \emph{not} be
%        capitalized (for example, "\@HwM@large@witch");
%      \item
%        the name of the ``public'' variant will be composed by exactly the same
%        words, again separated by "@"~characters, \emph{but} with each word
%        being also capitalized (for example, "\@HwM@Large@Witch").
%    \end{itemize}
%    Note, though, that the ``public'' variant of a macro will typically (but
%    not always) require the caller to specify a font selector like "\textfont";
%    we'll see that, from the point of view of the other parts of the code, this
%    is an acceptable requirement for the interface.
%
%    \subsubsection{Drawing the witch (and the cat)}
%
%    The following macros are responsible for the bulk of the task of drawing
%    the witch (with an optional cat).  Figure~\ref{fig:witch} shows a sketch of
%    this drawing.
%
%    \begin{figure}[tp]
%      \centering
%      The small variant:\\*[\bigskipamount]
%      \begin{picture}(6,4)(-3,-2)
%        \linethickness{.1pt}
%        \color{guidelines}
%        \multiput(-3,-2)(1,0){7}{\line(0,1){4}}
%        \multiput(-3,-2)(0,1){5}{\line(1,0){6}}
%        \color{black}
%        \linethickness{3pt}
%        \roundcap
%        \Line(-1,-1)(3,1)
%        \linethickness{1.5pt}
%        \Line(-1,-1)(-2.5,-1.25)
%        \Line(-1,-1)(-2.4,-1.5)
%        \Line(-1,-1)(-2.25,-1.75)
%        \Line(-1,-1)(-2,-2)
%        \put(-1.7,-.4){\magicstar{.4}}
%        \put(-2.7,-.8){\magicstar{.25}}
%        \Line(0,.9)(-.1,.7)
%        \polyline(.3,1.6)(.4,1.5)(.75,1.5)(.9,1.2)(.5,1.2)
%                (.6,1)(.8,.9)(.7,.75)(0,.9)(-.1,1)
%        \Line(.1,1.4)(.3,1.5)
%        \polygon*(-.5,1)(-1,0)(-1,-.5)(-.75,-1)(.5,-1)
%                (0,-1.8)(.2,-1.9)(.3,-1.7)(.4,-2)(1,-2)
%                (.5,-1.8)(.5,-1.5)(.8,-1.6)(1,-.75)(0,-.5)
%                (0,-.3)(.7,-.3)(.9,-.2)(1,0)(0,0)
%                (0,.7)
%        \polygon*(-1.5,1)(-1.4,1.5)(-1,2)(-.5,2)(0,1.75)
%                (.5,1.9)(1.25,1.75)(0,1.5)(-.5,1)(-1,.8)
%                (-1.2,1)(-1,1)(-.5,1.5)(-1,1.75)(-1.3,1.5)
%        ^^A
%        ^^A The cat:
%        \put(1.8,.5){\circle*{.6}}
%        \put(2.1,.7){\circle*{.5}}
%        \put(2.25,1){\circle*{.4}}
%        \polygon*(2.05,1)(2.05,1.25)(2.25,1.1)(2.45,1.25)(2.45,1)
%        \linethickness{3pt}
%        \cbezier(1.6,.3)(1,0)(2.1,-.2)(1.5,-.5)
%      \end{picture}
%
%      \bigskip\bigskip\bigskip
%
%      The large variant:\\*[\bigskipamount]
%      \begin{picture}(12,8)(-6,-4)
%        \linethickness{.1pt}
%        \color{guidelines}
%        \multiput(-6,-4)(1,0){13}{\line(0,1){8}}
%        \multiput(-6,-4)(0,1) {9}{\line(1,0){12}}
%        \color{black}
%        \roundcap
%        \linethickness{4pt}
%        \Line(-2,-2)(6,2)
%        \linethickness{2pt}
%        \Line(-2,-2)(-5,-2.5)
%        \Line(-2,-2)(-4.85,-2.95)
%        \Line(-2,-2)(-4.6,-3.3)
%        \Line(-2,-2)(-4.35,-3.65)
%        \Line(-2,-2)(-4,-4)
%        \put(-3,-1.2){\magicstar{.4}}
%        \put(-4.1,-.8){\magicstar{.8}}
%        \put(-5.4,-1.8){\magicstar{.6}}
%        \Line(0,1.8)(-.2,1.4)
%        \polyline(.6,3.2)(.8,3)(1.5,3)
%        \put(1.6,3){\oval(.2,.2)[tl]}
%        \put(1.6,3){\oval(.2,.2)[r]}
%        \polyline(1.6,2.9)(1.8,2.4)(1.2,2.4)(1,2.5)(1,2.3)
%                (1.2,2)(1.6,1.8)(1.7,1.8)(1.7,1.6)(1.4,1.5)
%                (0,1.8)(-.2,2)
%        \Line(.2,2.8)(.6,3)
%        \polygon*(-1,2)(-2,0)(-2,-1)(-1.5,-2)(1,-2)
%                (0,-3.6)(.4,-3.8)(.6,-3.4)(.8,-4)(2,-4)
%                (1,-3.6)(1,-3)(1.6,-3.2)(2,-1.5)(0,-1)
%                (0,-.6)(1.4,-.6)(1.8,-.4)(2,0)(0,0)
%                (0,1.4)
%        \polygon*(-3,2)(-2.8,3)(-2,4)(-1.5,4.1)(-1,4)(0,3.5)
%                (1,3.8)(2.5,3.5)(3,3.3)(2,3.4)(0,3)(-1,2)(-2,1.6)
%                (-2.7,2)(-2,2)(-1,3)(-2,3.5)(-2.6,3)
%        \linethickness{.4pt}
%        \Line(1.7,1.6)(2,1.6)
%        \Line(1.7,1.6)(1.9,1.4)
%        \Line(1.7,1.6)(1.7,1.3)
%        ^^A
%        ^^A The cat:
%        \put(3.6,1){\circle*{1.2}}
%        \put(4.2,1.4){\circle*{1}}
%        \put(4.5,2){\circle*{.8}}
%        \polygon*(4.1,2)(4.1,2.5)(4.5,2.2)(4.9,2.5)(4.9,2)
%        \linethickness{4pt}
%        \cbezier(3.2,.6)(2,0)(4.2,-.4)(3,-1)
%        \buttcap
%        \linethickness{.4pt}
%        \Line(3.8,2.1)(5.2,1.9)
%        \Line(3.8,2)(5.2,2)
%        \Line(3.8,1.9)(5.2,2.1)
%      \end{picture}
%
%      \caption{Sketches of the witch}
%      \label{fig:witch}
%    \end{figure}
%
%    \begin{macro}{\@HwM@large@witch}
%    This is the macro that draws the ``large'' version of the witch (for
%    "\displaystyle").  This is the ``private'' variant, with the following
%    parameters:
%    \begin{paramlist}
%      \param{1}
%        "l"~for a right-facing witch, "r"~for a left-facing one;\\
%      \param{2}
%        "r"~for a right-facing witch, "l"~for a left-facing one;\\
%      \param{3}
%        main drawing thickness, in units of the default-rule-thickness
%        "\fontdimen";\\
%      \param{4}
%        thickness of the broomstick and of the cat's tail, in the same units;\\
%      \param{5}
%        thickness of hair (beard, whiskers), in the same units.
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@large@witch[5]{%
  \begin{@HwM@large@picture}{12}{-6}%
    \roundcap
    \linethickness{#4\@HwM@thickness@units@for \textfont}%
    \Line(\-2,-2)(\+6,2)%
    \linethickness{#3\@HwM@thickness@units@for \textfont}%
    \Line(\-2,-2)(\-5,-2.5)%
    \Line(\-2,-2)(\-4.85,-2.95)%
    \Line(\-2,-2)(\-4.6,-3.3)%
    \Line(\-2,-2)(\-4.35,-3.65)%
    \Line(\-2,-2)(\-4,-4)%
    \put(\-3,-1.2){\@HwM@magic@star{.4}}%
    \put(\-4.1,-.8){\@HwM@magic@star{.8}}%
    \put(\-5.4,-1.8){\@HwM@magic@star{.6}}%
    \Line(0,1.8)(\-.2,1.4)%
    \polyline(\+.6,3.2)(\+.8,3)(\+1.5,3)%
    \put(\+1.6,3){\oval(.2,.2)[t#1]}%
    \put(\+1.6,3){\oval(.2,.2)[#2]}%
    \polyline(\+1.6,2.9)(\+1.8,2.4)(\+1.2,2.4)(\+1,2.5)(\+1,2.3)%
            (\+1.2,2)(\+1.6,1.8)(\+1.7,1.8)(\+1.7,1.6)(\+1.4,1.5)%
            (0,1.8)(\-.2,2)%
    \polygon*(\-1,2)(\-2,0)(\-2,-1)(\-1.5,-2)(\+1,-2)%
            (0,-3.6)(\+.4,-3.8)(\+.6,-3.4)(\+.8,-4)(\+2,-4)%
            (\+1,-3.6)(\+1,-3)(\+1.6,-3.2)(\+2,-1.5)(0,-1)%
            (0,-.6)(\+1.4,-.6)(\+1.8,-.4)(\+2,0)(0,0)%
            (0,1.4)%
    \polygon*(\-3,2)(\-2.8,3)(\-2,4)(\-1.5,4.1)(\-1,4)(0,3.5)%
            (\+1,3.8)(\+2.5,3.5)(\+3,3.3)(\+2,3.4)(0,3)(\-1,2)(\-2,1.6)%
            (\-2.7,2)(\-2,2)(\-1,3)(\-2,3.5)(\-2.6,3)%
    \buttcap
%    \end{macrocode}
%    The witch's eye:
%    \begin{macrocode}
    \Line(\+.2,2.8)(\+.6,3)%
%    \end{macrocode}
%    Rest of the code:
%    \begin{macrocode}
    \linethickness{#5\p@}%
    \Line(\+1.7,1.6)(\+2,1.6)%
    \Line(\+1.7,1.6)(\+1.9,1.4)%
    \Line(\+1.7,1.6)(\+1.7,1.3)%
    \if@HwM@cat@
      \Line(\+3.8,2.1)(\+5.2,1.9)%
      \Line(\+3.8,2)(\+5.2,2)%
      \Line(\+3.8,1.9)(\+5.2,2.1)%
      \roundcap
      \linethickness{#4\@HwM@thickness@units@for \textfont}%
      \put(\+3.6,1){\circle*{1.2}}%
      \put(\+4.2,1.4){\circle*{1}}%
      \put(\+4.5,2){\circle*{.8}}%
      \polygon*(\+4.1,2)(\+4.1,2.5)(\+4.5,2.2)(\+4.9,2.5)(\+4.9,2)%
      \cbezier(\+3.2,.6)(\+2,0)(\+4.2,-.4)(\+3,-1)%
    \fi
  \end{@HwM@large@picture}%
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@Large@Witch}
%    The ``public'' variant of the above, with the following parameters:
%    \begin{paramlist}
%      \param{1}
%        "l"~for a right-facing witch, "r"~for a left-facing one;\\
%      \param{2}
%        "r"~for a right-facing witch, "l"~for a left-facing one.
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@Large@Witch[2]{%
  \@HwM@choose@thicknesses{\@HwM@large@witch #1#2}%
        {{.4}{1.8}{.1}}%
        {{.8}{2.7}{.15}}%
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@common@small@body}
%    The macros that draw the ``small'' version of the witch (for styles others
%    than "\displaystyle") are more complex, because some parts of the drawing
%    are shared also by the extensible brooms ("\xrightwicthonbroom",
%    "\overrightwitchonbroom", and the like).  The following macro draws the
%    parts that are common to all such constructions.  This is the ``private''
%    variant, with the following parameters:
%    \begin{paramlist}
%      \param{1}
%        font selector (\emph{e.g.}, "\textfont");\\
%      \param{2}
%        line thickness for the witch's face, in relative units.
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@common@small@body[2]{%
  \linethickness{#2\@HwM@thickness@units@for #1}%
  \buttcap
%    \end{macrocode}
%    The witch's eye:
%    \begin{macrocode}
  \Line(\+.1,1.4)(\+.3,1.5)%
%    \end{macrocode}
%    Rest of the code:
%    \begin{macrocode}
  \roundcap
  \Line(0,.9)(\-.1,.7)%
  \polyline(\+.3,1.6)(\+.4,1.5)(\+.75,1.5)(\+.9,1.2)(\+.5,1.2)%
          (\+.6,1)(\+.8,.9)(\+.7,.75)(0,.9)(\-.1,1)%
  \polygon*(\-.5,1)(\-1,0)(\-1,-.5)(\-.75,-1)(\+.5,-1)%
          (0,-1.8)(\+.2,-1.9)(\+.3,-1.7)(\+.4,-2)(\+1,-2)%
          (\+.5,-1.8)(\+.5,-1.5)(\+.8,-1.6)(\+1,-.75)(0,-.5)%
          (0,.7)%
  \polygon*(\-1.5,1)(\-1.4,1.5)(\-1,2)(\-.5,2)(0,1.75)%
          (\+.5,1.9)(\+1.25,1.75)(0,1.5)(\-.5,1)(\-1,.8)%
          (\-1.2,1)(\-1,1)(\-.5,1.5)(\-1,1.75)(\-1.3,1.5)%
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@Common@Small@Body}
%    The ``public'' variant of the above; parameters:
%    \begin{paramlist}
%      \param{1}
%        font selector (\emph{e.g.}, "\textfont").
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@Common@Small@Body[1]{%
  \@HwM@choose@thicknesses {\@HwM@common@small@body #1}{{.35}}{{.7}}%
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@common@small@cat}
%    Draw the part of the cat that is shared also by the extensible brooms;
%    ``private'' variant, parameters are as follows:
%    \begin{paramlist}
%      \param{1}
%        font selector (\emph{e.g.}, "\textfont");\\
%      \param{2}
%        line thickness for the cat's tail, in relative units.
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@common@small@cat[2]{%
  \roundcap
  \linethickness{#2\@HwM@thickness@units@for #1}%
  \if@HwM@cat@
    \put(\+1.8,.5){\circle*{.6}}%
    \put(\+2.1,.7){\circle*{.5}}%
    \put(\+2.25,1){\circle*{.4}}%
    \polygon*(\+2.05,1)(\+2.05,1.25)(\+2.25,1.1)(\+2.45,1.25)(\+2.45,1)%
    \cbezier(\+1.8,.4)(\+1.2,.1)(\+2,-.1)(\+1.4,-.4)%
  \fi
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@Common@Small@Cat}
%    The ``public'' variant of the above; parameters:
%    \begin{paramlist}
%      \param{1}
%        font selector (\emph{e.g.}, "\textfont").
%    \end{paramlist}
%    \begin{macrocode}
\newcommand*\@HwM@Common@Small@Cat[1]{%
  \@HwM@choose@thicknesses {\@HwM@common@small@cat #1}{{}}{{2}}%
}
%    \end{macrocode}
%    \end{macro}
%
%    \begin{macro}{\@HwM@Small@Witch}
%    This is the macro that draws the complete ``small'' variant of the witch
%    (for styles other than "\displaystyle").  This one exists only in the
%    ``public'' variant, with the following arguments:
%    \begin{paramlist}
%      \param{1}
%        style selector (\emph{e.g.}, "\displaystyle");\\
%      \param{2}
%        font selector (\emph{e.g.}, "\textfont").
%    \end{paramlist}
%    The first parameter is imposed by the interface toward other parts of the
%    code, because other macros that share the same interface might need it, but
%    isn't actually used in this case.
%    \begin{macrocode}
\newcommand*\@HwM@Small@Witch[2]{%
  \begin{@HwM@small@picture}#2{6}{-3}%
    \@HwM@Common@Small@Cat #2%
    \Line(\-1,-1)(\+3,1)%
    \@HwM@Common@Small@Body #2%
    \Line(\-1,-1)(\-2.5,-1.25)%
    \Line(\-1,-1)(\-2.4,-1.5)%
    \Line(\-1,-1)(\-2.25,-1.75)%
    \Line(\-1,-1)(\-2,-2)%
    \put(\-1.7,-.4){\@HwM@magic@star{.4}}%
    \put(\-2.7,-.8){\@HwM@magic@star{.25}}%
    \polygon*(0,-.3)(\+.7,-.3)(\+.9,-.2)(\+1,0)(0,0)%
  \end{@HwM@small@picture}%
}
%    \end{macrocode}
%    \end{macro}
%
%    \textbf{Uncommented code} starts here.
%    \begin{macrocode}
%
% Drawing the small witch w/o the broom:
\newcommand*\@HwM@Small@Witch@Wo@Broom[1]{%
  \begin{@HwM@math@picture}{4}{-2}{}#1{0}{\+1}%
    \@HwM@Common@Small@Body #1%
    \polygon*(\-.1,.4)(\+1,-.9)(\+1,-1.2)(\+.8,-1.2)(\-.1,0)%
  \end{@HwM@math@picture}%
}
%
% Drawing the cat on a horizontal broomstick:
\newcommand*\@HwM@Small@Cat@On@Hori@Broom[1]{%
  \begin{@HwM@math@picture}{0}{-.6}{}#1{0}{\+2.5}%
    \@HwM@Common@Small@Cat #1%
    \Line(\+2.2,.8)(\+2.4,.4)%
  \end{@HwM@math@picture}%
}
%
% Pumpkins.
\newcommand*\@HwM@large@pumpkin@profile[1]{%
  \cbezier(#1.15,2.25)(#12.63,3.75)(#13.38,1.5)(#13.38,0)%
  \cbezier(#1.15,-2.7)(#12.4,-3.6)(#13.38,-1.5)(#13.38,0)%
  \put(#11.13,1.13){\circle*{.8}}%
}
\newcommand*\@HwM@large@pumpkin@mouth[9]{%
    \polygon*%
        % lower lip:
        (-#1)(-#2)(-#3)(-#4)(0,#5)(#4)(#3)(#2)(#1)%
        % upper lip:
        (#6)(#7)(#8)(0,#9)(-#8)(-#7)(-#6)%
}
\newcommand*\@HwM@large@pumpkin[1]{%
  \begin{@HwM@oplus@picture}\displaystyle \textfont {7.5}{-3.75}%
    \roundcap
    \linethickness{#1\@HwM@thickness@units@for \textfont}%
    \Line(-.15,2.25)(-.3,3)(.3,3)(.15,2.25)%
    \Line(-.15,-2.7)(.15,-2.7)%
    \@HwM@large@pumpkin@profile-%
    \@HwM@large@pumpkin@profile+%
    \polygon*(0,.35)(-.35,-.35)(.35,-.35)%
    \@HwM@large@pumpkin@mouth{2,-.5}{1.3,-1.4}{.8,-1.3}{.5,-1.6}%
        {-1.5}%
        {1.2,-1.1}{.7,-1}{.45,-1.1}%
        {-1}%
  \end{@HwM@oplus@picture}%
}
\newcommand*\@HwM@Large@Pumpkin{%
  \@HwM@choose@thicknesses \@HwM@large@pumpkin
        {{1.8}}%
        {{2.2}}%
}
\newcommand*\@HwM@small@pumpkin@profile[1]{%
  \cbezier(#1.1,1.5)(#11.75,2.5)(#12.25,1)(#12.25,0)%
  \cbezier(#1.1,-1.8)(#11.6,-2.4)(#12.25,-1)(#12.25,0)%
  \put(#1.75,.75){\circle*{.5}}%
}
\newcommand*\@HwM@small@pumpkin@mouth[7]{%
    \polygon*%
        % lower lip:
        (-#1)(-#2)(-#3)(0,#4)(#3)(#2)(#1)%
        % upper lip:
        (#5)(#6)(0,#7)(-#6)(-#5)%
}
\newcommand*\@HwM@small@pumpkin[3]{%
  \begin{@HwM@oplus@picture}#1#2{5}{-2.5}%
    \roundcap
    \linethickness{#3\@HwM@thickness@units@for #2}%
    \Line(-.1,1.5)(-.15,2)(.15,2)(.1,1.5)%
    \Line(-.1,-1.8)(.1,-1.8)%
    \@HwM@small@pumpkin@profile-%
    \@HwM@small@pumpkin@profile+%
    \polygon*(0,.2)(-.2,-.2)(.2,-.2)%
    \@HwM@small@pumpkin@mouth{1.3,-.3}{.8,-.8}{.5,-.7}%
        {-1}%
        {.7,-.6}{.4,-.5}%
        {-.7}%
  \end{@HwM@oplus@picture}%
}
\newcommand*\@HwM@Small@Pumpkin[2]{%
  \@HwM@choose@thicknesses{\@HwM@small@pumpkin #1#2}%
        {{}}%
        {{1.5}}%
}
\newcommand*\@HwM@oplus@pumpkin@profile[1]{%
  \cbezier(#1.1,1)(#11.2,1.7)(#11.6,.8)(#11.6,0)%
  \cbezier(#1.1,-1)(#11,-1.5)(#11.6,-.8)(#11.6,0)%
  \put(#1.6,.5){\circle*{.4}}%
}
\newcommand*\@HwM@oplus@pumpkin[3]{%
  \begin{@HwM@oplus@picture}#1#2{3.6}{-1.8}%
    \roundcap
    \linethickness{#3\@HwM@thickness@units@for #2}%
    \Line(-.1,1)(-.15,1.4)(.15,1.4)(.1,1)%
    \Line(-.1,-1)(.1,-1)%
    \@HwM@oplus@pumpkin@profile-%
    \@HwM@oplus@pumpkin@profile+%
    \@HwM@small@pumpkin@mouth{1,-.1}{.7,-.5}{.4,-.4}%
        {-.7}%
        {.6,-.3}{.3,-.2}%
        {-.4}%
  \end{@HwM@oplus@picture}%
}
\newcommand*\@HwM@Oplus@Pumpkin[2]{%
  \@HwM@choose@thicknesses{\@HwM@oplus@pumpkin #1#2}%
        {{.6}}%
        {{1.2}}%
}
%
% Clouds.
\newcommand*\@HwM@large@cloud[1]{%
  \begin{@HwM@large@picture}{12}{-6}%
    \roundcap
    \linethickness{#1\@HwM@thickness@units@for \textfont}%
    \cbezier(\-5,0)(\-7,.5)(\-5.5,3.25)(\-4,2.5)%
    \cbezier(\-3.8,2.1)(\-4.75,3.5)(\-2,4)(\-2,3)%
    \cbezier(\-2.4,2.5)(\-1.5,4)(\+2,5)(\+2,3)%
    \cbezier(\+1.8,2.8)(\+2.5,4)(\+4.5,2.5)(\+2.8,1.8)%
    \cbezier(\+3.2,2)(\+7,2)(\+6,0)(\+5,0)%
    \cbezier(\+5,0)(\+6,0)(\+6.25,-1)(\+5.3,-1.4)%
    \cbezier(\+4.6,-1.1)(\+6.8,-1.5)(\+4.3,-4)(\+3.6,-2.1)%
    \cbezier(\+3.9,-2.6)(\+4,-3)(\+2,-5)(0,-3)%
    \cbezier(\+.2,-2.4)(\-.2,-4.5)(\-4.5,-4)(\-4,-2)%
    \cbezier(\-3.4,-2)(\-5.5,-2)(\-6.5,-.5)(\-5,0)%
  \end{@HwM@large@picture}%
}
\newcommand*\@HwM@Large@Cloud{%
  \@HwM@choose@thicknesses \@HwM@large@cloud
        {{.8}}%
        {{1.6}}%
}
\newcommand*\@HwM@small@cloud[2]{%
  \begin{@HwM@small@picture}#1{6}{-3}%
    \roundcap
    \linethickness{#2\@HwM@thickness@units@for #1}%
    \cbezier(\-2.5,0)(\-3.5,.25)(\-3,2)(\-1,1.5)%
    \cbezier(\-1.2,1.25)(\-.75,2)(\+1,2.5)(\+1,1.5)%
    \cbezier(\+.9,1.4)(\+1.25,2)(\+2.25,1.25)(\+1.4,.9)%
    \cbezier(\+1.6,1)(\+3.5,1)(\+3,0)(\+2.5,0)%
    \cbezier(\+2.5,0)(\+3,0)(\+3.5,-1)(\+2.1,-1.2)%
    \cbezier(\+2.5,-1.1)(\+2.5,-2)(\+1,-2.5)(0,-1.5)%
    \cbezier(\+.1,-1.2)(\-.1,-2.25)(\-2.25,-2)(\-2,-1)%
    \cbezier(\-1.7,-1)(\-2.75,-1)(\-3.25,-.25)(\-2.5,0)%
  \end{@HwM@small@picture}%
}
\newcommand*\@HwM@Small@Cloud[2]{%
  \@HwM@choose@thicknesses{\@HwM@small@cloud #2}%
        {{.5}}%
        {{1.2}}%
}
%
% Ghosts.
\newcommand*\@HwM@symm@ghost@contour[8]{%
  \cbezier(-#1,#2)(-#3,#4)(-#3,#5)(-#3,#6)%
  \Line(-#3,#6)(-#3,#7)%
  \cbezier(#1,#2)(#3,#4)(#3,#5)(#3,#6)%
  \Line(#3,#6)(#3,#7)%
  \cbezier(-#3,#7)(-#3,#8)(#3,#8)(#3,#7)%
}
\newcommand*\@HwM@symm@ghost@border[8]{%
  \cbezier(-#1,#2)(-#3,#4)(-#5,#6)(-#7,#2)%
  \qbezier(-#7,#2)(0,#8)(#7,#2)%
  \cbezier(#1,#2)(#3,#4)(#5,#6)(#7,#2)%
}
\newcommand*\@HwM@symm@ghost@eyes[3]{%
  \put(-#1,#2){\circle*{#3}}%
  \put(#1,#2){\circle*{#3}}%
}
\newcommand*\@HwM@symmetric@ghost[3]{%
  \begin{@HwM@math@picture}{2.6}{-1}%
            {\@HwM@d@pict@strut{.6}}#1{3.2}{-1.6}%
    \roundcap
    \linethickness{#2\@HwM@thickness@units@for #1}%
    \@HwM@symm@ghost@contour{1.5}{-1.5}{1}{-1}{-.5}{0}{.5}{2}%
    \linethickness{#3\@HwM@thickness@units@for #1}%
    \@HwM@symm@ghost@border{1.5}{-1.5}{1.1}{-1.1}{.7}{-1.9}{.3}{-1.2}%
    \@HwM@symm@ghost@eyes{.4}{.7}{.4}%
  \end{@HwM@math@picture}%
}
\newcommand*\@HwM@Symmetric@Ghost[2]{%
  \@HwM@choose@thicknesses{\@HwM@symmetric@ghost #2}%
        {{.9}{.6}}%
        {{1.8}{1.2}}%
}
\newcommand*\@HwM@asymmetric@ghost[3]{%
  \begin{@HwM@math@picture}{2.6}{-1}%
            {\@HwM@d@pict@strut{.6}}#1{3.8}%
            {-\@HwM@right@or@left{1.6}{2.2}}%
    \roundcap
    \linethickness{#2\@HwM@thickness@units@for #1}%
    \cbezier(\-1.75,-1.5)(\-1,-1)(\-.7,-.5)(\-.5,0)%
    \cbezier(\-.5,0)(\-.3,.5)(0,1.6)(\+1,1.6)%
    \cbezier(\+1,1.6)(\+1.8,1.6)(\+1.8,.9)(\+1.8,.6)%
    \cbezier(\+1.8,.6)(\+1.8,-.3)(\+.9,-.7)(\+1.25,-1.5)%
    \linethickness{#3\@HwM@thickness@units@for #1}%
    \cbezier(\-1.75,-1.5)(\-1.4,-1.2)(\-1.1,-1.8)(\-.75,-1.5)%
    \cbezier(\-.75,-1.5)(\-.4,-1.2)(\-.1,-1.8)(\+.25,-1.5)%
    \cbezier(\+.25,-1.5)(\+.6,-1.2)(\+.9,-1.8)(\+1.25,-1.5)%
    \put(\+1.2,.7){\circle*{.4}}%
  \end{@HwM@math@picture}%
}
\newcommand*\@HwM@Asymmetric@Ghost[2]{%
  \@HwM@choose@thicknesses{\@HwM@asymmetric@ghost #2}%
        {{.9}{.6}}%
        {{1.8}{1.2}}%
}

% Extensible arrow-like symbols.
\newlength\@HwM@arrowfill@skip
%    \end{macrocode}
%
%    \begin{macro}{\@HwM@auto@font@selector}
%    Suppose you have \meta{something} (\emph{e.g.}, a macro token) that expects
%    to be followed by a pair \meta{style selector}\meta{font selector}, where
%    \meta{style selctor} is a single token like "\displaystyle" or
%    "\scriptscriptstyle", and \meta{font selector} is a single token like
%    "\textfont" or "\scriptfont"; then
%    \begin{flushleft}
%      "\@HwM@auto@font@selector{"\meta{something}"}"\meta{style selector}
%    \end{flushleft}
%    is transformed into
%    \begin{flushleft}
%      \meta{something}\meta{style selector}\meta{font selector}
%    \end{flushleft}
%    where \meta{style selector} is the same style selector as the one that was
%    originally present, and \meta{font selector} is the correct font selector
%    associated with it (that is, "\textfont" for "\displaystyle" and
%    "\textstyle", and so on).  For example,
%    \begin{flushleft}
%      "\@HwM@auto@font@selector{"\meta{something}"}\scriptstyle"
%    \end{flushleft}
%    is transformed into
%    \begin{flushleft}
%      \meta{something}"\scriptstyle\scriptfont"
%    \end{flushleft}
%    In other words, prepending \meta{something} with "\@HwM@auto@font@selector"
%    turns it from something that requires the two arguments \meta{style
%    selector}\meta{font selector} into something else that takes just the
%    single argument \meta{style selector}: the appropriate \meta{font selector}
%    will be automatically supplied (whence the name of this macro).
%    \textbf{Beware:} the following is a simple implementation that relies on
%    assignments and that is therefore \emph{not} purely expandable.
%    \begin{macrocode}
\newcommand*\@HwM@auto@font@selector[2]{%
  \def\@tempa{#1}%
  \edef\@tempb{%
    \ifx\displaystyle #2%
      \textfont
    \else \ifx\textstyle #2%
      \textfont
    \else \ifx\scriptstyle #2%
      \scriptfont
    \else \ifx\scriptscriptstyle #2%
      \scriptscriptfont
    \fi\fi\fi\fi
  }%
  \expandafter \@tempa \expandafter #2\@tempb
}
%    \end{macrocode}
%    \end{macro}
%
%    \textbf{Uncommented code} again.
%    \begin{macrocode}
\newcommand*\@HwM@extended@arrowfill@[2]{%
  % #1 is the "leaders" (pseudo-)macro (must gobble 2 arguments)
  % #2 is the minimal width in math units
  \@HwM@auto@font@selector
        {\@HwM@stylefont@arrowfill{#1}{#2}}%
}
\newcommand*\@HwM@stylefont@arrowfill[4]{%
  % #1 is the "leaders" (pseudo-)macro (must gobble 2 arguments)
  % #2 is the minimal width in math units
  % #3 is style selector (e.g., "\displaystyle")
  % #4 is font selector (e.g., "\textfont")
  $\m@th
    \thickmuskip 0mu%
    \medmuskip  \thickmuskip
    \thinmuskip \thickmuskip
    \setlength\@HwM@arrowfill@skip
        {#2\fontdimen 6 #4\tw@ \@plus \@ne fill}%
    #3%
    #1#3#4%
  $%
}
\newcommand*\@HwM@enriched@arrowfill@[5]{%
  % #1, #2, and #3 are the three characters
  % #4 and #5 are the two additional macros (both with 2 arguments)
  % its call must be followed by the argument for the minimal width
  \@HwM@extended@arrowfill@
        {\HwM@arrowfill@cleaders{#1}{#2}{#3}{#4}{#5}}%
}
\newcommand*\HwM@arrowfill@cleaders[7]{%
  % #1, #2, and #3 are the three characters
  % #4 and #5 are the two additional macros (both with 2 arguments)
  % #6 is style selector (e.g., "\displaystyle")
  % #7 is font selector (e.g., "\textfont")
  #4#6#7%
  \relax #1\mkern-7mu%
  \cleaders\hbox{$#6\mkern-2mu#2\mkern-2mu$}\hskip\@HwM@arrowfill@skip
  \mkern-7mu#3\relax
  #5#6#7%
}
\newcommand*\@HwM@rightbroomfill@Wwac@{%
  \@HwM@set@right@dir
  \@HwM@enriched@arrowfill@ \ni\relbar\relbar
        \@gobbletwo
        \@HwM@right@add@witch@cat
        \@ne
}
\newcommand*\@HwM@right@add@witch@cat[2]{%
  \hskip -\glueexpr \@HwM@arrowfill@skip/\tw@ \relax
  \@HwM@Small@Witch@Wo@Broom #2%
  \if@HwM@cat@
    \hskip \glueexpr \@HwM@arrowfill@skip/4 \relax
    \@HwM@Small@Cat@On@Hori@Broom #2%
    \hskip \glueexpr \@HwM@arrowfill@skip/4 \relax
  \else
    \hskip \glueexpr \@HwM@arrowfill@skip/\tw@ \relax
  \fi
}%
\newcommand*\@HwM@leftbroomfill@Wwac@{%
  \@HwM@set@left@dir
  \@HwM@enriched@arrowfill@ \relbar\relbar\in
        \@HwM@left@add@witch@cat
        \@gobbletwo
        \@ne
}
\newcommand*\@HwM@left@add@witch@cat[2]{%
  \if@HwM@cat@
    \hskip \glueexpr \@HwM@arrowfill@skip/4 \relax
    \@HwM@Small@Cat@On@Hori@Broom #2%
    \hskip \glueexpr \@HwM@arrowfill@skip/4 \relax
  \else
    \hskip \glueexpr \@HwM@arrowfill@skip/\tw@ \relax
  \fi
  \@HwM@Small@Witch@Wo@Broom #2%
  \hskip -\glueexpr \@HwM@arrowfill@skip/\tw@ \relax
}
\newcommand*\@HwM@init@swish@dimens[1]{%
  \dimen4 \glueexpr \fontdimen 22 #1\tw@ *\tw@/\thr@@
  \dimen6 .25\@HwM@thickness@units@for #1%
  \dimen@ \dimen4
  \@HwM@calc@swish@thickness
}
\newcommand*\@HwM@calc@swish@thickness{%
  \dimen@ii -\dimen@
  \advance \dimen@ii \dimen6
}
\newcommand*\@HwM@swish@leaders{%
  \leaders \hrule \@height\dimen@ \@depth\dimen@ii \hskip
}
\newcommand*\@HwM@right@ghost@swish[2]{%
  \@HwM@init@swish@dimens #2%
  \hskip \glueexpr \@HwM@arrowfill@skip/4\relax
  \@HwM@swish@leaders \glueexpr \@HwM@arrowfill@skip/4\relax
  \hskip \glueexpr \@HwM@arrowfill@skip/8\relax
  \@HwM@swish@leaders \glueexpr \@HwM@arrowfill@skip*\thr@@/8\relax
  \hskip -\@HwM@arrowfill@skip
  \advance \dimen@ \dimen4
  \@HwM@calc@swish@thickness
  \@HwM@swish@leaders \glueexpr \@HwM@arrowfill@skip*\thr@@/4 \relax
  \hskip \glueexpr \@HwM@arrowfill@skip/8\relax
  \@HwM@swish@leaders
        \glueexpr \@HwM@arrowfill@skip/8+\dimen4 /\tw@ \relax
  \hskip -\glueexpr \@HwM@arrowfill@skip/\tw@ \relax
  \advance \dimen@ \dimen4
  \@HwM@calc@swish@thickness
  \@HwM@swish@leaders
        \glueexpr \@HwM@arrowfill@skip/\tw@ +\dimen4 /\tw@ \relax
  \kern -\dimen4
  \mathrightghost
}
\newcommand*\@HwM@left@ghost@swish[2]{%
  \mathleftghost
  \@HwM@init@swish@dimens #2%
  \@HwM@swish@leaders \glueexpr \@HwM@arrowfill@skip*\thr@@/8\relax
  \hskip \glueexpr \@HwM@arrowfill@skip/8\relax
  \@HwM@swish@leaders \glueexpr \@HwM@arrowfill@skip/4\relax
  \hskip -\glueexpr \@HwM@arrowfill@skip*\thr@@/4+\dimen4 /\tw@ \relax
  \advance \dimen@ \dimen4
  \@HwM@calc@swish@thickness
  \@HwM@swish@leaders
        \glueexpr \@HwM@arrowfill@skip/8+\dimen4 /\tw@\relax
  \hskip \glueexpr \@HwM@arrowfill@skip/8\relax
  \@HwM@swish@leaders \glueexpr \@HwM@arrowfill@skip*\thr@@/4\relax
  \hskip -\glueexpr \@HwM@arrowfill@skip +\dimen4 \relax
  \advance \dimen@ \dimen4
  \@HwM@calc@swish@thickness
  \@HwM@swish@leaders
        \glueexpr \@HwM@arrowfill@skip/\tw@ +\dimen4 /\tw@ \relax
  \hskip \glueexpr \@HwM@arrowfill@skip/\tw@ +\dimen4 /\tw@ \relax
}
\newcommand*\@HwM@rightghostfill@{%
  \@HwM@extended@arrowfill@ \@HwM@right@ghost@swish {.5}%
}
\newcommand*\@HwM@leftghostfill@{%
  \@HwM@extended@arrowfill@ \@HwM@left@ghost@swish {.5}%
}

% three versions of "\mathpalette" adapted to our needs:
\newcommand*\@HwM@dblstyle@mathpalette[2]{%
  % Works like "\mathpalette", but macro passed in #1 must take
  % (at least) three arguments, of which the first _two_ are
  % style selections.
  \mathchoice
    {#1\displaystyle      \scriptstyle       {#2}}%
    {#1\textstyle         \scriptstyle       {#2}}%
    {#1\scriptstyle       \scriptscriptstyle {#2}}%
    {#1\scriptscriptstyle \scriptscriptstyle {#2}}%
}
\newcommand*\@HwM@variable@mathpalette[2]{%
  \mathchoice
      {#1}%
      {#2\textstyle         \textfont        }%
      {#2\scriptstyle       \scriptfont      }%
      {#2\scriptscriptstyle \scriptscriptfont}%
}
\newcommand*\@HwM@constant@mathpalette[1]{%
  \mathchoice
      {#1\displaystyle      \textfont        }%
      {#1\textstyle         \textfont        }%
      {#1\scriptstyle       \scriptfont      }%
      {#1\scriptscriptstyle \scriptscriptfont}%
}

% General calls:
\newcommand*\@HwM@general@large@operator[2]{%
  \mathop{%
    \@HwM@variable@mathpalette{#1}{#2}%
  }\slimits@
}
\newcommand*\@HwM@general@inner@symbol[2]{%
  \mathinner{%
    \@HwM@variable@mathpalette{#1}{#2}%
  }%
}
\newcommand*\@HwM@general@binary@operation[1]{%
  \mathbin{%
    \@HwM@constant@mathpalette{#1}%
  }%
}
\newcommand*\@HwM@general@ordinary@symbol[1]{%
  \mathord{%
    \@HwM@constant@mathpalette{#1}%
  }%
}
\newcommand*\@HwM@ifstar@cat[1]{%
    \@ifstar
        {\@HwM@cat@true  #1}%
        {\@HwM@cat@false #1}%
}

%
% User-level commands:
\newcommand*\mathwitch{%
  \DOTSB
  \@HwM@set@right@dir
  \@HwM@ifstar@cat{\@HwM@mathwitch lr}%
}
\newcommand*\reversemathwitch{%
  \DOTSB
  \@HwM@set@left@dir
  \@HwM@ifstar@cat{\@HwM@mathwitch rl}%
}
\newcommand*\@HwM@mathwitch[2]{%
  \@HwM@general@large@operator {\@HwM@Large@Witch #1#2}\@HwM@Small@Witch
}

\newcommand*\pumpkin{%
  \DOTSB
  \@HwM@general@binary@operation \@HwM@Oplus@Pumpkin
}
\newcommand*\bigpumpkin{%
  \DOTSB
  \@HwM@general@large@operator \@HwM@Large@Pumpkin \@HwM@Small@Pumpkin
}
\@ifdefinable\greatpumpkin{\let\greatpumpkin=\bigpumpkin}

\newcommand*\mathcloud       {\@HwM@set@right@dir \@HwM@mathcloud}
\newcommand*\reversemathcloud{\@HwM@set@left@dir  \@HwM@mathcloud}
\newcommand*\@HwM@mathcloud{%
  \@HwM@general@inner@symbol \@HwM@Large@Cloud \@HwM@Small@Cloud
}

\newcommand*\mathghost{%
  \@HwM@general@ordinary@symbol \@HwM@Symmetric@Ghost
}
\newcommand*\mathrightghost{\@HwM@set@right@dir \@HwM@mathghost}
\newcommand*\mathleftghost {\@HwM@set@left@dir  \@HwM@mathghost}
\newcommand*\@HwM@mathghost{%
  \@HwM@general@ordinary@symbol \@HwM@Asymmetric@Ghost
}
%
% Accents.
\newcommand*\@HwM@dblstyle@overarrow@[4]{%
  % #1 := stretchable covering arrow
  % #2 := base style
  % #3 := style for covering arrow
  % #4 := base symbol
  \vbox{\ialign{##\crcr
    #1#3\crcr
    \noalign{\nointerlineskip}%
    $\m@th\hfil #2#4\hfil$\crcr
  }}%
}
\newcommand*\@HwM@dblstyle@underarrow@[4]{%
  % #1 := stretchable underlying arrow
  % #2 := base style
  % #3 := style for underlying arrow
  % #4 := base symbol
  \vtop{\ialign{##\crcr
    $\m@th\hfil #2#4\hfil$\crcr
    \noalign{\nointerlineskip \kern\ex@}%
    #1#3\crcr
  }}%
}
\newcommand*\@HwM@general@ou@w@cat[1]{%
  \@HwM@ifstar@cat{\@HwM@dblstyle@mathpalette{#1}}%
}
\newcommand*\overrightwitchonbroom{%
  \@HwM@general@ou@w@cat
    {\@HwM@dblstyle@overarrow@ \@HwM@rightbroomfill@Wwac@}%
}
\newcommand*\overleftwitchonbroom{%
  \@HwM@general@ou@w@cat
    {\@HwM@dblstyle@overarrow@ \@HwM@leftbroomfill@Wwac@}%
}
\newcommand*\overrightswishingghost{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@overarrow@ \@HwM@rightghostfill@}%
}
\newcommand*\overleftswishingghost{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@overarrow@ \@HwM@leftghostfill@}%
}
\newcommand*\underrightwitchonbroom{%
  \@HwM@general@ou@w@cat
    {\@HwM@dblstyle@underarrow@ \@HwM@rightbroomfill@Wwac@}%
}
\newcommand*\underleftwitchonbroom{%
  \@HwM@general@ou@w@cat
    {\@HwM@dblstyle@underarrow@ \@HwM@leftbroomfill@Wwac@}%
}
\newcommand*\underrightswishingghost{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@underarrow@ \@HwM@rightghostfill@}%
}
\newcommand*\underleftswishingghost{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@underarrow@ \@HwM@leftghostfill@}%
}
%
% The script version of standard over/under arrows.
\newcommand*\overscriptrightarrow{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@overarrow@ \rightarrowfill@}%
}
\newcommand*\overscriptleftarrow{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@overarrow@ \leftarrowfill@}%
}
\newcommand*\overscriptleftrightarrow{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@overarrow@ \leftrightarrowfill@}%
}
\newcommand*\underscriptrightarrow{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@underarrow@ \rightarrowfill@}%
}
\newcommand*\underscriptleftarrow{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@underarrow@ \leftarrowfill@}%
}
\newcommand*\underscriptleftrightarrow{%
  \@HwM@dblstyle@mathpalette
    {\@HwM@dblstyle@underarrow@ \leftrightarrowfill@}%
}
%
% Extensible "arrow-like" symbols.
\newcommand*\@HwM@ext@arrow@w@cat[5]{%
  \def\@HwM@tempa{\ext@arrow {#1}{#2}{#3}{#4}{#5}}%
  \@HwM@ifstar@cat{\@HwM@ext@arrow@w@cat@x}%
}
\newcommand*\@HwM@ext@arrow@w@cat@x[2][]{%
  \@HwM@tempa {#1}{#2}%
}
\newcommand*\xrightwitchonbroom{%
  \@HwM@ext@arrow@w@cat 9395\@HwM@rightbroomfill@Wwac@%
}
\newcommand*\xleftwitchonbroom{%
  \@HwM@ext@arrow@w@cat 3959\@HwM@leftbroomfill@Wwac@%
}
\newcommand*\xrightswishingghost[2][]{%
  \ext@arrow 3{12}5{15}\@HwM@rightghostfill@{#1}{#2}%
}
\newcommand*\xleftswishingghost[2][]{%
  \ext@arrow {12}3{15}5\@HwM@leftghostfill@{#1}{#2}%
}
%    \end{macrocode}
%
%    End of the module for the \packlass{\halloweenmath} package.
%    \begin{macrocode}
%</halloweenmath>
%    \end{macrocode}
%
% \section{End of input}
%
%    The usual "\endinput" which prevents the \DS\ program from putting
%    garbage into the generated files.
%    \begin{macrocode}
\endinput
%    \end{macrocode}
%
% \Finale
%