eplain 3.1 (5dec06)

git-svn-id: svn://tug.org/texlive/trunk@2630 c570f23f-e606-0410-a88d-b1316a301751

1 files changed, 0 insertions, 4783 deletions

diff --git a/Master/texmf-dist/source/eplain/base/xeplain.tex b/Master/texmf-dist/source/eplain/base/xeplain.tex
deleted file mode 100644
index 5464d27a82e..00000000000
--- a/Master/texmf-dist/source/eplain/base/xeplain.tex
+++ /dev/null
@@ -1,4783 +0,0 @@
-% xeplain.tex: macros for nonformatting.  Written 1989--94 by (mostly)
-% Karl Berry. Some additions/changes 1997--98 by Adam Lewenberg. 
-% These macros are in the public domain.
-% 
-% This is the ``extended plain'' TeX format that's described in
-% `eplain.texinfo', which you should have received with this file.  We
-% assume plain has been loaded.
-%
-% N.B.: A version number is defined at the beginning and end of this file;
-% please change those numbers whenever the file is modified!
-% And it's best to rename the file if you're going to distribute a
-% modified version.
-%
-% Some macros were written and/or suggested by Paul Abrahams.
-% Other sources (e.g., The TeXbook) are cited at the appropriate places.
-% 
-%% @texfile{
-%%   author = "Karl Berry, Steven Smith, Oleg Katsitadze, and others",
-%%   version = "REPLACE-WITH-VERSION",
-%%   date = "REPLACE-WITH-DATE",
-%%   filename = "xeplain.tex",
-%%   email = "bug-eplain@tug.org",
-%%   checksum = "REPLACE-WITH-CHECKSUM",
-%%   codetable = "ASCII",
-%%   supported = "yes",
-%%   docstring = "This file defines macros that extend and expand on
-%%                plain TeX. eplain.tex is xeplain.tex and the other
-%%                source files with comments stripped; see the original
-%%                files for author credits, etc.  And please base diffs
-%%                or other contributions on xeplain.tex, not the
-%%                stripped-down eplain.tex.",
-%% }
-%
-%
-% Load eplain.tex only once (to avoid using up \new's). 
-% \eplain is defined at the end of this file, so we can test \eplain to
-% detect whether eplain.tex has been loaded already or not. 
-% 
-% We use \expandafter because the merge script strips any lines
-% with an \endinput.
-%
-\ifx\eplain\undefined
-  \let\next\relax
-\else
-  \expandafter\let\expandafter\next\csname endinput\endcsname
-\fi
-\next
-% The ifpdf.sty file included below was written by Heiko Oberdiek.
-% See the complete source file (e.g., in this distribution) for
-% comments.
-%% [[[include ifpdf.sty]]]
-% 
-% 
-% Category codes, etc.
-%
-\def\makeactive#1{\catcode`#1 = \active \ignorespaces}%
-\chardef\letter = 11
-\chardef\other = 12
-% The following two macros were adopted from miniltx.tex of graphics.
-\def\makeatletter{%
-  \edef\resetatcatcode{\catcode`\noexpand\@\the\catcode`\@\relax}%
-  \catcode`\@11\relax
-}%
-\def\makeatother{%
-  \edef\resetatcatcode{\catcode`\noexpand\@\the\catcode`\@\relax}%
-  \catcode`\@12\relax
-}%
-% 
-% 
-% So we can have user-inaccessible control sequences.
-% 
-\edef\leftdisplays{\the\catcode`@}%
-\catcode`@ = \letter
-\let\@eplainoldatcode = \leftdisplays
-%
-% Save miniscule amounts of memory and time by writing \toks@ii instead
-% of \toks2.
-\toksdef\toks@ii = 2
-% 
-% 
-% This macro is defined in The TeXbook, but it never made it
-% into plain TeX.  \dospecials is defined there, though.
-% 
-\def\uncatcodespecials{%
-   \def\do##1{\catcode`##1 = \other}%
-   \dospecials
-}%
-%
-% 
-% Here is a way to do \let^^M = \cs, where the \let need not be global.
-{%
-   \makeactive\^^M %
-   \long\gdef\letreturn#1{\let^^M = #1}%
-}%
-% 
-% 
-% Swallow parameters, etc.
-% 
-\let\@eattoken = \relax  % Define this, so \eattoken can be used in \edef.
-\def\eattoken{\let\@eattoken = }%
-\def\gobble#1{}%
-\def\gobbletwo#1#2{}%
-\def\gobblethree#1#2#3{}%
-%
-% We can't just use \empty as the identity function, since then outer
-% braces which would supposedly delimit the argument would define a group.
-\def\identity#1{#1}%
-% 
-% True if #1 is the empty string, i.e., called like `\ifempty{}'.
-% Use notes:
-% So far, \ifempty works in the following cases:
-% 1. \ifempty{}\message{empty}\else\message{not empty}\fi --> empty
-% 2. \ifempty\undefined\message{empty}\else\message{not empty}\fi --> not empty
-%   But does NOT work in the case
-% 3. \def\empty{}
-%    \ifempty\empty\message{empty}\else\message{not empty}\fi --> not empty
-% Question: When should \ifempty be true?
-\def\@emptymarkA{\@emptymarkB} 
-% The above line suggested by Stanislav Brabec.
-\def\ifempty#1{\@@ifempty #1\@emptymarkA\@emptymarkB}%
-\def\@@ifempty#1#2\@emptymarkB{\ifx #1\@emptymarkA}%
-%
-% Turn a definition into the characters that compose it.  See
-% ``Sanitizing control sequences under \write'', by Ron Whitney, TUGboat
-% 11(4), p.620.
-\def\@gobblemeaning#1:->{}%
-\def\sanitize{\expandafter\@gobblemeaning\meaning}%
-%
-% 
-% From p.308 of the TeXbook.  This cannot be used in places where TeX
-% might be skipping tokens, e.g., in conditionals.
-% 
-\def\ifundefined#1{\expandafter\ifx\csname#1\endcsname\relax}%
-% 
-% 
-% \csname constructions come up an awful lot, so we save typing with the
-% following.  (But the extra macro expansion does take time, so we don't
-% use these in frequently-executed code.)
-% 
-\def\csn#1{\csname#1\endcsname}%
-\def\ece#1#2{\expandafter#1\csname#2\endcsname}%
-%
-% 
-% \expandonce{TOKEN} abbreviates \expandafter\noexpand TOKEN.
-% 
-\def\expandonce{\expandafter\noexpand}%
-%
-%
-% Don't show our register allocations in the log.
-% 
-\let\@plainwlog = \wlog
-\let\wlog = \gobble
-%
-% 
-% Make it convenient to put newlines in error messages.
-% 
-\newlinechar = `^^J
-% 
-%
-% Sometimes it is convenient to have everything in the transcript file
-% and nothing on the terminal.  We don't just call \tracingall here,
-% since that produces some useless output on the terminal.
-%
-\def\gloggingall{\begingroup \globaldefs = 1 \loggingall \endgroup}%
-\def\loggingall{\tracingcommands\tw@\tracingstats\tw@
-   \tracingpages\@ne\tracingoutput\@ne\tracinglostchars\@ne
-   \tracingmacros\tw@\tracingparagraphs\@ne\tracingrestores\@ne
-   \showboxbreadth\maxdimen\showboxdepth\maxdimen
-}%
-% Show the complete contents of boxes.
-%
-\def\tracingboxes{\showboxbreadth = \maxdimen \showboxdepth = \maxdimen}%
-%
-% Don't trace anything, except restore \showbox... to plain's values.
-% 
-\def\gtracingoff{\begingroup \globaldefs = 1 \tracingoff \endgroup}%
-\def\tracingoff{\tracingonline\z@\tracingcommands\z@\tracingstats\z@
-  \tracingpages\z@\tracingoutput\z@\tracinglostchars\z@
-  \tracingmacros\z@\tracingparagraphs\z@\tracingrestores\z@
-  \showboxbreadth5 \showboxdepth3
-}%
-%
-% 
-% Definitions to produce actual `{' (et al.) characters in an output
-% file via \write.  We omit the line break after the first }, since we
-% have no comment character at that point.
-% 
-\begingroup
-  \catcode`\{ = 12 \catcode`\} = 12
-  \catcode`\[ = 1 \catcode`\] = 2
-  \gdef\lbracechar[{]%
-  \gdef\rbracechar[}]%
-  \catcode`\% = \other
-  \gdef\percentchar[%]\endgroup
-%
-% 
-% Leave horizontal mode (if we're in it), then insert a penalty.
-% And conversely.
-% 
-\def\vpenalty{\ifhmode\par\fi \penalty}%
-\def\hpenalty{\ifvmode\leavevmode\fi \penalty}%
-%
-% 
-% Make \else usable in \loop.  From Victor Eijkhout's TeX by Topic (page
-% 104).  See also Alois Kabelschacht, TUGboat 8(2), page 184.
-%
-\def\iterate{%
-  \let\loop@next\relax
-  \body
-  \let\loop@next\iterate
-  \fi
-  \loop@next
-}%
-% 
-% 
-% Add #2 (which is expanded in an \edef) to the end of the definition of
-% #1 (which must be a previously-defined control sequence).  This is a
-% way to construct simple lists.
-% 
-\def\edefappend#1#2{%
-  \toks@ = \expandafter{#1}%
-  \edef#1{\the\toks@ #2}%
-}%
-%
-% 
-% \allowhyphens, from TeXbook, p. 395.  Allows following & preceding word
-% to be hyphenated.
-%
-\def\allowhyphens{\nobreak\hskip\z@skip}%
-%
-% 
-% 
-%  Hooks.
-%
-% \hookaction{HOOK}{TOKENS} adds TOKENS to the list of actions for
-% HOOK.  We avoid defining a \toks register for each hook, although
-% maybe that isn't so important.
-% 
-% \hookappend and \hookprepend add TOKENS specificially to the end or
-% the beginning.  When the argument is used, \toks@ will be the previous
-% value of the hook, and \toks@ii the new tokens.
-%
-\long\def\hookprepend{\@hookassign{\the\toks@ii \the\toks@}}%
-\long\def\hookappend{\@hookassign{\the\toks@ \the\toks@ii}}%
-\let\hookaction = \hookappend % either one should be ok
-%
-% 
-% \@hookassign{LAST-DEF}{HOOK}{TOKENS} makes \toks@ the previous value
-% of HOOK, and \toks@ii TOKENS, and then assigns the new value using
-% LASTDEF.  We store the hook in a control sequence \@HOOKhook.
-% 
-\long\def\@hookassign#1#2#3{%
-  % Make \toks@ be the expansion (to one level) of \@HOOKhook, or empty.
-  \expandafter\ifx\csname @#2hook\endcsname \relax
-    % If \@HOOKhook was undefined, let it be empty.
-    \toks@ = {}%
-  \else
-    % Otherwise, expand it to one level.  We can't just assign from
-    % \expandafter{\csname ...} since then the \toks register would
-    % contain the control sequence, not its definition.
-    \expandafter\let\expandafter\temp \csname @#2hook\endcsname
-    \toks@ = \expandafter{\temp}%
-  \fi
-  \toks2 = {#3}% Don't expand the argument all the way.
-  \ece\edef{@#2hook}{#1}%
-}%
-%
-% 
-% \hookactiononce{HOOK}\CS adds `\global\let\CS=\relax' to the
-% definition of \CS, then adds to HOOK.  Thus, \CS is expanded the next
-% time HOOK is called, but then it goes away.  This only works if \CS is
-% expandable, though.
-% 
-\long\def\hookactiononce#1#2{%
-  \edefappend#2{\global\let\noexpand#2\relax}
-  \hookaction{#1}#2%
-}%
-%
-% 
-% \hookrun{HOOKNAME} runs whatever actions have been defined for HOOK.
-% 
-\def\hookrun#1{%
-  \expandafter\ifx\csname @#1hook\endcsname \relax \else
-    % Isn't this fun?  We want to get rid of the \fi before expanding
-    % the actions, so that they can read what's coming up next.
-    \def\temp{\csname @#1hook\endcsname}%
-    \expandafter\temp
-  \fi
-}%
-%
-% 
-% 
-%  Properties a la Lisp.
-%
-% \setproperty{ATOM}{PROPNAME}{VALUE} defines the property PROPNAME on the
-% ``atom'' ATOM to have VALUE.
-% 
-\def\setproperty#1#2#3{\ece\edef{#1@p#2}{#3}}%
-\def\setpropertyglobal#1#2#3{\ece\xdef{#1@p#2}{#3}}%
-%
-% 
-% \getproperty{ATOM}{PROPNAME} expands to the value of the property
-% PROPNAME on ATOM, or to nothing (i.e., \empty), if the property isn't
-% present.
-% 
-\def\getproperty#1#2{%
-  \expandafter\ifx\csname#1@p#2\endcsname\relax
-  % then \empty
-  \else \csname#1@p#2\endcsname
-  \fi
-}%
-%
-% 
-% 
-%  Macros to support BibTeX are in a separate file, btxmac.tex.
-% 
-% (They are maintained separately, too, by Oren Patashnik,
-% opbibtex@cs.stanford.edu.)  btxmac.tex also defines other macros we
-% want to use and make available.
-% 
-% But not all people want to read the BibTeX macros, because of either
-% space or time considerations.  Therefore, we look for \nobibtex,
-% which, if defined, causes btxmac.tex not to be read.  But we still
-% have to get \tokstostring et al. defined---so eplain.tex contains
-% those definitions, automatically edited in from btxmac.tex.  All the
-% documentation has been removed, so you must read btxmac.tex if you
-% want the comments.
-% 
-% 
-% We want to give a slightly different message than btxmac if no .aux
-% file exists (unless the person using us has already define some
-% message, possibly empty.)
-% 
-\ifx\@undefinedmessage\@undefined
-  \def\@undefinedmessage
-    {No .aux file; I won't warn you about undefined labels.}%
-\fi
-%
-% 
-% We use a token register to define all the BibTeX definitions, to avoid
-% problems with the \if... constructions when they are conditionally
-% read.
-% 
-%% [[[here is the first set of common definitions from btxmac]]]
-\toks0 = {%
-  %% [[[here are the BibTeX-specific definitions from btxmac]]]
-}%
-\ifx\nobibtex\@undefined \the\toks0 \fi
-%% [[[here is the second set of common definitions from btxmac]]]
-%
-% Here are the control sequences that btxmac.tex defines using an @,
-% because btxmac.tex wants to absolutely minimize the chance of
-% conflicts.  But these control sequence implement documented features
-% of eplain, so we want to allow people to use them without the @.
-% 
-\let\auxfile = \@auxfile
-\let\for = \@for
-\let\futurenonspacelet = \@futurenonspacelet
-\def\iffileexists{\if@fileexists}%
-\let\innerdef = \@innerdef
-\let\innernewcount = \@innernewcount
-\let\innernewdimen = \@innernewdimen
-\let\innernewif = \@innernewif
-\let\innernewwrite = \@innernewwrite
-\let\linenumber = \@linenumber
-\let\readauxfile = \@readauxfile
-\let\spacesub = \@spacesub
-\let\testfileexistence = \@testfileexistence
-\let\writeaux = \@writeaux
-% 
-%
-% btxmac.tex defines \innerdef.  Let's use it to make an abbreviation
-% for \innerdef\inner<name>{<name>}.
-% 
-\def\innerinnerdef#1{\expandafter\innerdef\csname inner#1\endcsname{#1}}%
-%
-% Use that in turn to make non-outer versions of the rest of plain TeX's
-% allocation macros.  (btxmac.tex already did a few of them.)
-% 
-\innerinnerdef{newbox}%
-\innerinnerdef{newfam}%
-\innerinnerdef{newhelp}%
-\innerinnerdef{newinsert}%
-\innerinnerdef{newlanguage}%
-\innerinnerdef{newmuskip}%
-\innerinnerdef{newread}%
-\innerinnerdef{newskip}%
-\innerinnerdef{newtoks}%
-% 
-% 
-% Besides doing a \write to the aux file, we also need to do an
-% \immediate\write.
-% 
-\def\immediatewriteaux#1{%
-  \ifx\noauxfile\@undefined
-    \immediate\write\@auxfile{#1}%
-  \fi
-}%
-%
-%
-% We want \biblabelprint to define hyperlink destination.  For that,
-% we save the label for the current bibliography entry from within
-% \bblitemhook.
-\def\bblitemhook#1{\gdef\@hlbblitemlabel{#1}}%
-%
-\def\biblabelprint#1{%
-   \noindent
-   \hbox to \biblabelwidth{%
-      \hldest@impl{bib}{\@hlbblitemlabel}%
-      \biblabelprecontents
-      \biblabelcontents{#1}%
-      \biblabelpostcontents
-   }%
-   \kern\biblabelextraspace
-}%
-% We want each citation item to be hyperlink to bibliography entry.
-% To avoid unnecessary warnings about undefined destinations (e.g.,
-% from pdfTeX), produce the link only when .bbl file (which does the
-% \hldest's) is present.
-\def\eplainprintcitepreitem#1{\hlstart@impl{cite}{#1}}%
-\def\eplainprintcitepostitem{\hlend@impl{cite}}%
-%
-%
-\def\printcitepreitem#1{%
-  \testfileexistence[\bblfilebasename]{bbl}%
-  \iffileexists
-    \global\let\printcitepreitem\eplainprintcitepreitem
-    \global\let\printcitepostitem\eplainprintcitepostitem
-  \else
-    \global\let\printcitepreitem\gobble
-    \global\let\printcitepostitem\relax
-  \fi
-  \printcitepreitem{#1}%
-}%
-% 
-% 
-% 
-%  Macros that produce output.
-% 
-% \obeywhitespace makes both end-of-lines and spaces in the input be
-% respected in the output.  Even spaces at the beginning of lines turn
-% into blank space the size of the natural space of the current font.
-% The reason why plain TeX's \obeyspaces does not do this last is that
-% it produces actual space characters, i.e., glue, and glue is discarded
-% at a(n output) line break, and so if line breaks in the input are
-% line breaks in the output...
-% 
-% Tabs are not affected; they will still produce glue (a single space).
-%
-\begingroup
-   \makeactive\^^M \makeactive\ % No spaces or ^^M's from here on.
-\gdef\obeywhitespace{%
-\makeactive\^^M\def^^M{\par\futurelet\next\@finishobeyedreturn}%
-\makeactive\ \let =\ %
-%
-% The group we use here is the one \obeywhitespace must be enclosed in.
-% If we don't do this, then if the obeyed stuff ends in a newline, the
-% indent produced by the definition of ^^M will make that line indented,
-% even if it isn't the end of the paragraph.
-\aftergroup\@removebox%
-\futurelet\next\@finishobeywhitespace%
-}%
-%
-% \@finishobeywhitespace eats any spaces and/or the end-of-line after
-% the \obeywhitespace command itself.  The group here is the one that it
-% itself creates.
-%
-\gdef\@finishobeywhitespace{{%
-\ifx\next %
-\aftergroup\@obeywhitespaceloop%
-\else\ifx\next^^M%
-\aftergroup\gobble%
-\fi\fi}}%
-%
-% \@finishobeyedreturn is invoked at the end of every input line.  We
-% check if the next thing is also a return, and, if so, insert extra
-% space.  Then we start the next line.
-% 
-\gdef\@finishobeyedreturn{%
-\ifx\next^^M\vskip\blanklineskipamount\fi%
-\indent%
-}%
-\endgroup
-%
-% The argument here is the space that we are supposed to eat after the
-% \obeywhitespace command.
-% 
-\def\@obeywhitespaceloop#1{\futurelet\next\@finishobeywhitespace}%
-% 
-% 
-% This removes the last box, if it was a empty box of width \parindent.
-% We might have been called inside a \vbox, so we have to test if we are
-% in horizontal mode before using \lastbox.
-% 
-\def\@removebox{%
-  \ifhmode
-    \setbox0 = \lastbox
-    \ifdim\wd0=\parindent
-      \setbox2 = \hbox{\unhbox0}%
-      \ifdim\wd2=0pt
-        % Don't put it back: it was an indentation box.
-        % This \ignorespaces ignores spaces after the group.
-        \ignorespaces
-      \else
-        \box2 % Put it back: it wasn't empty.
-      \fi
-    \else
-       \box0 % Put it back: it wasn't the right width.
-    \fi
-  \fi
-}%
-%
-% We allow for extra (possibly negative) space when we hit blank lines.
-% 
-\newskip\blanklineskipamount
-\blanklineskipamount = 0pt
-%
-% 
-% A good way to print fractions in text when you don't want
-% to use \over (which should be most of the time), and yet
-% just `1/2' doesn't look right.  (From the TeXbook,
-% the answer to exercise 11.6, p.311.)
-% 
-\def\frac#1/#2{\leavevmode
-   \kern.1em \raise .5ex \hbox{\the\scriptfont0 #1}%
-   \kern-.1em $/$%
-   \kern-.15em \lower .25ex \hbox{\the\scriptfont0 #2}%
-}%
-%
-% 
-% The `e' just means `Eplain', as in `Eplain's hrule'.  The advantage
-% to using these is that you can change the default thickness.
-% 
-\newdimen\hruledefaultheight  \hruledefaultheight = 0.4pt
-\newdimen\hruledefaultdepth   \hruledefaultdepth = 0.0pt
-\newdimen\vruledefaultwidth   \vruledefaultwidth = 0.4pt
-%
-\def\ehrule{\hrule height\hruledefaultheight depth\hruledefaultdepth}%
-\def\evrule{\vrule width\vruledefaultwidth}%
-%
-%
-% The texnames.sty and path.sty files included below were originally
-% written by Nelson Beebe and Philip Taylor, respectively. See the
-% complete source files (e.g., in this distribution) for comments.
-%% [[[include texnames.sty]]]
-%% [[[include path.sty]]]
-%
-% 
-% A square box, suitable for being a marker in lists.
-% 
-\def\blackbox{\vrule height .8ex width .6ex depth -.2ex \relax}% square bullet
-%
-% 
-% From p.311 of the TeXbook.
-% 
-% Make an unfilled rectangle with the dimensions of \box0.  #1 is the
-% height of the rules, #2 the depth (i.e., the thicknesses).
-% 
-\def\makeblankbox#1#2{%
-  \ifvoid0
-    \errhelp = \@makeblankboxhelp
-    \errmessage{Box 0 is void}%
-  \fi
-  \hbox{\lower\dp0
-    \vbox{\hidehrule{#1}{#2}%
-      \kern -#1% overlap rules
-      \hbox to \wd0{\hidevrule{#1}{#2}%
-        \raise\ht0\vbox to #1{}% vrule height
-        \lower\dp0\vtop to #1{}% vrule depth
-        \hfil\hidevrule{#2}{#1}%
-      }%
-      \kern-#1\hidehrule{#2}{#1}%
-    }%
-  }%
-}%
-%
-\newhelp\@makeblankboxhelp{Assigning to the dimensions of a void^^J%
-  box has no effect.  Do `\string\setbox0=\string\null' before you^^J%
-  define its dimensions.}%
-%
-% 
-% Produce an hrule with height #1 and depth #2, and insert kerning so it
-% doesn't change the current position.
-% 
-\def\hidehrule#1#2{\kern-#1\hrule height#1 depth#2 \kern-#2}%
-%
-% Produce a vrule with width #1+#2, kerning so as not to change the
-% current position.
-% 
-\def\hidevrule#1#2{%
-  \kern-#1%
-  \dimen@=#1\advance\dimen@ by #2%
-  \vrule width\dimen@
-  \kern-#2%
-}%
-% 
-% 
-% The \boxit macro from the TeXbook, trivially generalized to allow
-% something other than 3pt around the TeX box being boxed.
-% 
-\newdimen\boxitspace \boxitspace = 3pt
-%
-\long\def\boxit#1{%
-  \vbox{%
-    \ehrule
-    \hbox{%
-      \evrule
-      \kern\boxitspace
-      \vbox{\kern\boxitspace \parindent = 0pt #1\kern\boxitspace}%
-      \kern\boxitspace
-      \evrule
-    }%
-    \ehrule
-  }%
-}%
-%
-% 
-% Produce the written-out form of a number.
-% 
-\def\numbername#1{\ifcase#1%
-   zero%
-   \or one%
-   \or two%
-   \or three%
-   \or four%
-   \or five%
-   \or six%
-   \or seven%
-   \or eight%
-   \or nine%
-   \or ten%
-   \or #1%
-   \fi
-}%
-%
-% The following arrow macros were written by Steven Smith. See arrow.tex.
-\let\@plainnewif = \newif
-\let\@plainnewdimen = \newdimen
-\let\newif = \innernewif
-\let\newdimen = \innernewdimen
-\edef\@eplainoldandcode{\the\catcode`& }%
-\catcode`& = 11
-\toks0 = {%
-  %% [[[include arrow1]]]
-}%
-\catcode`& = 4
-\toks2 = {%
-  %% [[[include arrow2]]]
-}%
-\let\newif = \@plainnewif
-\let\newdimen = \@plainnewdimen
-\ifx\noarrow\@undefined \the\toks0 \the\toks2 \fi
-\catcode`& = \@eplainoldandcode
-% 
-% 
-% 
-%  Environments.
-% 
-% Define an ``environment'': arbitrary text, enclosed by \begingroup and
-% \endgroup.  But you get to label the group, so that if you forget an
-% \environment or an \endenvironment, you will probably get an error
-% message about it.
-% 
-% Since the environment names appear in \errmessage arguments, it's best
-% to keep them to `letter' and `other' characters.  I suppose we could
-% call \tokstostring to allow more general labels.
-% 
-% These macros improve slightly on the answer to exercise 5.7 in
-% The TeXbook, by making some checks on \begingroup and \endgroup, as
-% well as just making sure \environment and \endenvironment's match.
-% 
-%
-\def\environment#1{%
-   \ifx\@groupname\@undefined\else
-      % This gets invoked if we have two \environments (and no matching
-      % \endenvironment to the first) with an \endgroup in between.
-      \errhelp = \@unnamedendgrouphelp
-      \errmessage{`\@groupname' was not closed by \string\endenvironment}%
-   \fi
-   % Use \edef in case we are passed a macro that contains the name,
-   % instead of the name.
-   \edef\@groupname{#1}%
-   \begingroup
-      \let\@groupname = \@undefined
-}%
-%
-\def\endenvironment#1{%
-   \endgroup
-   \edef\@thearg{#1}%
-   \ifx\@groupname\@thearg
-   \else
-      \ifx\@groupname\@undefined
-         % Unfortunately, one gets an `extra \endgroup' message before
-         % seeing this.  But we have to restore \@groupname, so I see no
-         % alternative. 
-         \errhelp = \@isolatedendenvironmenthelp
-         \errmessage{Isolated \string\endenvironment\space for `#1'}%
-      \else
-         \errhelp = \@mismatchedenvironmenthelp
-         \errmessage{Environment `#1' ended, but `\@groupname' started}%
-         \endgroup % Probably a typo in the names.
-      \fi
-   \fi
-   \let\@groupname = \@undefined
-}%
-%
-\newhelp\@unnamedendgrouphelp{Most likely, you just forgot an^^J%
-   \string\endenvironment.  Maybe you should try inserting another^^J%
-   \string\endgroup to recover.}%
-%
-\newhelp\@isolatedendenvironmenthelp{You ended an environment X, but^^J%
-   no \string\environment{X} to start it is anywhere in sight.^^J%
-   You might also be at an \string\endenvironment\space that would match^^J%
-   a \string\begingroup, i.e., you forgot an \string\endgroup.}%
-%
-\newhelp\@mismatchedenvironmenthelp{You started an environment named X, but^^J%
-   you ended one named Y.  Maybe you made a typo in one^^J%
-   or the other of the names?}%
-% 
-% 
-% The above sort of environment allows nesting.  But environments
-% shouldn't always be allowed to nest (like the \flushright,
-% \flushleft, and \center ones defined below).  Here are some macros to
-% help deal with that.
-% 
-% \checkenv goes at the beginning of a macro that is
-% going to define the environment.
-% 
-\newif\ifenvironment
-\def\checkenv{\ifenvironment \errhelp = \@interwovenenvhelp
-   \errmessage{Interwoven environments}%
-   \egroup \fi
-}%
-%
-\newhelp\@interwovenenvhelp{Perhaps you forgot to end the previous^^J%
-   environment? I'm finishing off the current group,^^J%
-   hoping that will fix it.}%
-%
-% 
-% 
-%  Mathematics displays.
-%
-% By default, TeX centers displayed material.  To get left-justified
-% displays, say \leftdisplays.  To go back to centered displays, say
-% \centereddisplays.
-% 
-% This is based on an approach developed by Donald Arseneau,
-% asnd@triumfrg.bitnet.
-% 
-\newtoks\previouseverydisplay
-% Here we want to make ordinary math displays flush left, 
-% indented by the dimen \leftdisplayindent, which defaults
-% to \parindent.
-%
-% How do you want the first column aligned?
-\let\@leftleftfill\relax % as it was
-%\let\@leftleftfill\hfill % makes more sense, but could be too ugly
-%
-% Surely it makes more sense to not sum \leftdisplayindent+\parindent
-\newdimen\leftdisplayindent \leftdisplayindent=\parindent
-\newif\if@leftdisplays
-%
-\def\leftdisplays{%
-  \if@leftdisplays\else
-    \previouseverydisplay = \everydisplay
-    \everydisplay = {\the\previouseverydisplay \leftdisplaysetup}%
-    \let\@save@maybedisableeqno = \@maybedisableeqno
-    \let\@saveeqno = \eqno
-    \let\@saveleqno = \leqno
-    \let\@saveeqalignno = \eqalignno
-    \let\@saveleqalignno = \leqalignno
-    \let\@maybedisableeqno = \relax
-    \def\eqno{\hfill\textstyle\enspace}%
-    \def\leqno{%
-      \hfill
-      \hbox to0pt\bgroup
-        \kern-\displaywidth
-        % was: \kern-\displayindent % really \displayindent?  
-        \kern-\leftdisplayindent    % I'll use just \leftdisplayindent
-        $\aftergroup\@leftleqnoend  % inserted after ending $
-    }%
-    \@redefinealignmentdisplays
-    \@leftdisplaystrue
-  \fi
-}%
-\newbox\@lignbox
-\newdimen\disprevdepth
-
-% In order to use $$ for left-aligned equation we have to
-% put something like \leftline{$\displaystyle ...$} in the
-% display.  Then \eqno works basically like \hfill.
-% In order to make $$<assignments>\eqalignno{...}$$ work as
-% expected, including page breaks, we have to get rid of the
-% horizontal box, and un-vbox the alignment.  Sadly, \unvbox
-% does not perform baselineskip handing, so we need to get
-% the \prevdepth ourselves...in order to get the prevdepth,
-% the outermost display must be an alignment display.
-% Therefore, an ordinary $$ a=b $$ becomes:
-% $$\halign{#\cr\noalign{\disprevdepth = \prevdepth
-%       \leftline{$\displaystyle a=b$}
-%   }}$$
-%
-\def\centereddisplays{%
-  % If \leftdisplays hasn't been called, don't try to restore all the
-  % stuff it changes.
-  % 
-  \if@leftdisplays
-    \everydisplay = \previouseverydisplay
-    \let\@maybedisableeqno = \@save@maybedisableeqno
-    \let\eqno = \@saveeqno
-    \let\leqno = \@saveleqno
-    \let\eqalignno = \@saveeqalignno
-    \let\leqalignno = \@saveleqalignno
-    \@leftdisplaysfalse
-  \fi
-}%
-%
-\def\leftdisplaysetup{%
-%  surely not this *and* \leftdisplayindent? :  \dimen@ = \parindent
-   \dimen@ = \leftdisplayindent
-   \advance\dimen@ by \leftskip
-   \advance\displayindent by \dimen@
-   \advance\displaywidth by -\dimen@
-%  this outermost alignment doesn't align anything.
-   \halign\bgroup##\cr \noalign\bgroup
-      \disprevdepth = \prevdepth
-      \setbox\z@ = \hbox to\displaywidth\bgroup
-      %  Why strut??  \strut
-      %  Why this??   \advance\hsize by -\displayindent
-      $\displaystyle
-      \aftergroup\@lefteqend % inserted after ending $
-}
-%
-\def\@lefteqend{% gets inserted between the ending $$
-   \hfil\egroup% end box 0
-   \@putdisplay}
-% gets inserted between trailing $$.
-\def\@leftleqnoend{\hss \egroup $}% end the \hbox to 0pt for \leqno, restore $
-%
-\def\@putdisplay{%
-   \ifvoid\@lignbox %  Ordinary display; use it.
-     \moveright\displayindent\box\z@ 
-   \else % alignment display; unwrap alignment
-     \prevdepth = \dp\@lignbox % affects the skip *below*
-     \unvbox\@lignbox
-   \fi
-   \egroup\egroup % end \noalign, end outer \halign
-   $% restore first $ of trailing $$
-}
-%
-\def\@redefinealignmentdisplays{%
-  \def\displaylines##1{
-    \global\setbox\@lignbox\vbox{%
-      \prevdepth = \disprevdepth
-      \displ@y
-      \tabskip\displayindent
-      \halign{\hbox to\displaywidth
-        {$\@lign\displaystyle####\hfil$\hfil}\crcr
-              ##1\crcr}}}%
-  \def\eqalignno##1{%
-    \def\eqno{&}%
-    \global\setbox\@lignbox\vbox{%
-      \prevdepth = \disprevdepth
-      \displ@y
-      \advance\displaywidth by \displayindent
-      \tabskip\displayindent
-      \halign to\displaywidth{%
-         \hfil $\@lign\displaystyle{####}$\@leftleftfill\tabskip\z@skip
-        &$\@lign\displaystyle{{}####}$\hfil\tabskip\centering
-        &\llap{$\@lign####$}\tabskip\z@skip\crcr
-        ##1\crcr}}}%
-  \def\leqalignno##1{%
-    \def\eqno{&}%
-    \global\setbox\@lignbox\vbox{%
-      \prevdepth = \disprevdepth
-      \displ@y
-      \advance\displaywidth by \displayindent
-      \tabskip\displayindent
-      \halign to\displaywidth{%
-         \hfil $\@lign\displaystyle{####}$\@leftleftfill\tabskip\z@skip
-        &$\@lign\displaystyle{{}####}$\hfil\tabskip\centering
-        &\kern-\displaywidth 
-%         \showthe\displayindent \showthe\leftdisplayindent
-         \rlap{\kern\displayindent \kern-\leftdisplayindent$\@lign####$}%
-         \tabskip\displaywidth\crcr
-        ##1\crcr}}}%
-}%
-% 
-% \noalign is typically used to insert a few words (`and', for example)
-% between two aligned equations.  So I don't think the \noaligned
-% material should be indented.  Since \noalign takes <vertical mode
-% material>, we would end up with double indentation, anyway: one
-% because we're indenting the whole display, and one at the start of the
-% <v.m.m.>.  (If you want to change any of this, you can put something in
-% \@everynoalign.)  So, we use this definition for \noalign in a
-% left-justified \eqalignno:
-% 
-\let\@primitivenoalign = \noalign
-\newtoks\@everynoalign
-\def\@lefteqalignonoalign#1{%
-  \@primitivenoalign{%
-    % Is it right to set \leftskip=0pt first, thus perhaps making this
-    % work in lists and so forth?  We just compensate for the other ways
-    % the display is indented here.
-    \advance\leftskip by -\parindent
-    \advance\leftskip by -\leftdisplayindent
-    \parskip = 0pt
-    %
-    % We use \parindent=0pt instead of \noindent because the latter
-    % starts unrestricted horizontal mode, which means the alignment
-    % we're inside will wind up being as wide as the page.  When the arg
-    % is just vertical material, this is wrong.  For example, using
-    % \matrix inside \eqalignno fails if \noindent is used.
-    \parindent = 0pt
-    \the\@everynoalign
-    #1%
-  }%
-}%
-% 
-% 
-% 
-%  Time macros.
-% 
-% TeX sets \time, \day, \month, and \year when it begins.  (And does not
-% update them as it runs!)
-% 
-% 
-% \monthname produces the name of the month, abbreviated to three
-% letters.  The primitive \month should never be zero.
-% 
-\def\monthname{%
-   \ifcase\month
-      \or Jan\or Feb\or Mar\or Apr\or May\or Jun%
-      \or Jul\or Aug\or Sep\or Oct\or Nov\or Dec%
-   \fi
-}%
-%
-% \fullmonthname is like \monthname, except it doesn't abbreviate.
-% 
-\def\fullmonthname{%
-   \ifcase\month
-      \or January\or February\or March\or April\or May\or June%
-      \or July\or August\or September\or October\or November\or December%
-   \fi
-}%
-%
-% \timestring produces the current time, in a format like `1:14 p.m.'.
-% 
-\def\timestring{\begingroup
-   \count0 = \time
-   \divide\count0 by 60
-   \count2 = \count0   % The hour, from zero to 23.
-   %
-   \count4 = \time
-   \multiply\count0 by 60
-   \advance\count4 by -\count0   % The minute, from zero to 59.
-   % But we need the minutes with a leading zero, if necessary.
-   \ifnum\count4<10
-      \toks1 = {0}%
-   \else
-      \toks1 = {}%
-   \fi
-   % 
-   % Convert the hour into `a.m.' or `p.m.', and make it mod 12.
-   \ifnum\count2<12
-      \toks0 = {a.m.}%
-   \else
-      \toks0 = {p.m.}%
-      \advance\count2 by -12
-   \fi
-   %
-   % If it's midnight, call it `12', not `0'.
-   \ifnum\count2=0
-      \count2 = 12
-   \fi
-   %
-   % Produce the output.
-   \number\count2:\the\toks1 \number\count4 \thinspace \the\toks0
-\endgroup}%
-%
-%
-% \timestamp produces a text string for the whole thing like
-% `23 Apr 1964  1:14 p.m.'.
-%
-\def\timestamp{\number\day\space\monthname\space\number\year\quad\timestring}%
-%
-% 
-% \today produces the current date, as in `23 April 1964'.
-% 
-\def\today{\the\day\ \fullmonthname\ \the\year}%
-%
-% 
-% 
-%  (Typographical) lists.
-% 
-% These macros can produce numbered or unnumbered lists.
-% 
-% You can change the spacing by assigning new values to these registers.
-% They are used by both kinds of lists.  \listleftindent is relative to
-% the current paragraph indentation, while \listrightindent is an
-% absolute value.  I do this for two reasons: (1) it is more useful, if not
-% more ``logical'', to make list indentation depend on the paragraph
-% indentation; (2) footnotes do not work if \parindent is zero, and
-% having a footnote in a list item is perfectly reasonable.
-% 
-% If you change \baselineskip and want \abovelistskip and \belowlistskip
-% to retain their meanings here, you will have to reassign to them.  The
-% \baselineskip here is the value at the time eplain.tex is read, i.e.,
-% 12pt (most likely).
-% 
-% If the items in your lists are very long, you might want to
-% make \interitemskipamount nonzero.  
-% 
-\newskip\abovelistskipamount      \abovelistskipamount = .5\baselineskip
-  \newcount\abovelistpenalty      \abovelistpenalty    = 10000
-  \def\abovelistskip{\vpenalty\abovelistpenalty \vskip\abovelistskipamount}%
-\newskip\interitemskipamount      \interitemskipamount = 0pt
-  \newcount\belowlistpenalty      \belowlistpenalty    = -50
-  \def\belowlistskip{\vpenalty\belowlistpenalty \vskip\belowlistskipamount}%
-\newskip\belowlistskipamount      \belowlistskipamount = .5\baselineskip
-  \newcount\interitempenalty      \interitempenalty    = 0
-  \def\interitemskip{\vpenalty\interitempenalty \vskip\interitemskipamount}%
-\newdimen\listleftindent    \listleftindent = 0pt
-\newdimen\listrightindent   \listrightindent = 0pt        
-\let\listmarkerspace = \enspace
-%
-% To do arbitrary things at the start of each list:
-\newtoks\everylist
-%
-% If you want no space between items for a particular list
-% (perhaps because the items in it are short), you can say,
-% e.g., \numberedlist\listcompact.
-% 
-\def\listcompact{\interitemskipamount = 0pt \relax}%
-%
-% This is called to set up the parameters by both sorts of lists.
-% Because we set \rightskip, we finish off the current paragraph.
-% 
-\newdimen\@listindent
-%
-\def\beginlist{%
-  % Insert the space above this list, before we change \leftskip
-  % (because the \vskip in here might be what ends the paragraph).
-  \abovelistskip
-  %
-  \@listindent = \parindent
-  \advance\@listindent by \listleftindent
-  %
-  % \leftskip shifts nested lists to the right on the page.
-  \advance\leftskip by \@listindent
-  \advance\rightskip by \listrightindent
-  %
-  % We always need \itemnumber, so we can know whether an item is the
-  % first one or not.
-  \itemnumber = 1
-  %
-  \the\everylist
-}%
-%
-% A list item, for both kinds of lists.
-% 
-\def\li{\@getoptionalarg\@finli}%
-\def\@finli{%
-  % Save \@optionalarg in case \interitemskip garble it.
-  \let\@lioptarg\@optionalarg
-  % Write xref definition but do not define hyperlink destination
-  % (\printitem will do it).
-  \ifx\@lioptarg\empty \else
-    \begingroup
-      \@@hldestoff
-      \expandafter\writeitemxref\expandafter{\@lioptarg}%
-    \endgroup
-  \fi
-  \ifnum\itemnumber=1 \else \interitemskip \fi
-  % Add hyperlink destination in front of \marker before doing \printitem.
-  \begingroup
-    \ifx\@lioptarg\empty \else
-      \toks@ = \expandafter{\@lioptarg}%
-      \let\li@nohldest@marker\marker
-      \edef\marker{\noexpand\hldest@impl{li}{\the\toks@}\noexpand\li@nohldest@marker}%
-    \fi
-    \printitem
-  \endgroup
-  \advance\itemnumber by 1
-  \advance\itemletter by 1
-  \advance\itemromannumeral by 1
-  %
-  % Just in case somebody creeps in with an argument or something.
-  \ignorespaces
-}%
-%
-% \writeitemxref{LABEL} writes out a definition for LABEL to be \marker
-% for the aux file.
-% 
-\def\writeitemxref#1{\definexref{#1}\marker{item}}%
-%
-% \printitem is used to print items by both sorts of lists.  A \par gets
-% produced before every item -- even the first one.  We also want to
-% make paragraphs after the first appear to be indented -- i.e., they
-% will have double indentation.  It is usually bad exposition to have
-% lists with multiparagraph items, but sometimes it is unavoidable.
-% 
-\def\printitem{%
-  \par
-  \nobreak
-  \vskip-\parskip
-  \noindent
-  \printmarker\marker
-}%
-%
-% Output the list marker.
-% 
-\def\printmarker#1{\llap{\marker \enspace}}%
-%
-% Common ending.
-% 
-\def\endlist{\belowlistskip}%
-%
-% 
-% \numberedlist produces items which are numbered sequentially, starting
-% from one.  You start items with \li (`list item').  End the list with
-% \endnumberedlist.
-% 
-% A nested \numberedlist produces items labelled `(a)', `(b)', etc.  A
-% doubly (and deeper) nested \numberedlist labels items with `*'.
-% 
-% These registers keep track of where we are.
-% 
-\newcount\numberedlistdepth
-\newcount\itemnumber
-\newcount\itemletter
-\newcount\itemromannumeral
-%
-\def\numberedmarker{%
-  \ifcase\numberedlistdepth
-      (impossible)%
-  \or \printitemnumber
-  \or \printitemletter
-  \or \printitemromannumeral
-  \else *%
-  \fi
-}%
-%
-% These produce the text of the labels.  We use \the\itemletter so that
-% the value will expand.
-% 
-\def\printitemnumber{\number\itemnumber}%
-\def\printitemletter{\char\the\itemletter}%
-\def\printitemromannumeral{\romannumeral\itemromannumeral}%
-\def\numberedprintmarker#1{\llap{#1) \listmarkerspace}}%
-%
-\def\numberedlist{\environment{@numbered-list}%
-  % This is set back to zero by getting to the end of the group.
-  \advance\numberedlistdepth by 1
-  \itemletter = `a
-  \itemromannumeral = 1
-  \beginlist
-  \let\marker = \numberedmarker
-  \let\printmarker = \numberedprintmarker
-}%
-%
-\def\endnumberedlist{%
-  \par
-  \endenvironment{@numbered-list}%
-  \endlist
-}%
-%
-% Allow synonyms for \numberedlist.
-\let\orderedlist = \numberedlist
-\let\endorderedlist = \endnumberedlist
-% 
-% 
-% 
-% \unorderedlist produces items which are labelled with bullets.  You
-% start an item with \li, just as with numbered lists.  You end the list
-% with \endunorderedlist.
-% 
-% A nested \unorderedlist produces items labelled with em-dashes.  A
-% doubly (and deeper) nested \unorderedlist uses `*'.
-% 
-\newcount\unorderedlistdepth
-%
-\def\unorderedmarker{%
-  \ifcase\unorderedlistdepth
-      (impossible)%
-  \or \blackbox
-  \or ---%
-  \else *%
-  \fi
-}%
-\def\unorderedprintmarker#1{\llap{#1\listmarkerspace}}%
-%
-\def\unorderedlist{\environment{@unordered-list}%
-  \advance\unorderedlistdepth by 1
-  \beginlist
-  \let\marker = \unorderedmarker
-  \let\printmarker = \unorderedprintmarker
-}%
-%
-\def\endunorderedlist{%
-  \par
-  \endenvironment{@unordered-list}%
-  \endlist
-}%
-%
-% 
-% 
-%  Verbatim listing.
-% 
-% ... well, almost verbatim.  We assume the font \tt has all the
-% characters that will appear.  Control characters, except for tabs and
-% form feeds (and returns) won't produce anything useful.  Tabs produce
-% a fixed amount of space, and form feeds produce a page break.
-% 
-% This is based on Knuth's ideas in Appendix D of the TeXbook, p. 380.
-% The argument should be a filename.
-% 
-% if you need to do something more for your particular fonts and/or
-% environment before the file is input, give a definition to
-% \setuplistinghook.  If you want line numbers on the output, you can
-% say \let\setuplistinghook = \linenumberedlisting.
-% 
-\def\listing#1{%
-   \par \begingroup
-   \@setuplisting
-   \setuplistinghook
-   \input #1
-   \endgroup
-}%
-%
-\let\setuplistinghook = \relax
-%
-\def\linenumberedlisting{%
-  \ifx\lineno\undefined \innernewcount\lineno \fi
-  \lineno = 0
-  \everypar = {\advance\lineno by 1 \printlistinglineno}%
-}%
-\def\printlistinglineno{\llap{[\the\lineno]\quad}}%
-%
-% 
-% \uncatcodespecials must come before \obeywhitespace, lest a space
-% character in the input produce character 32 from the \tt font.
-% Ensure ^^L is active and non-outer.
-% 
-{%
-  \makeactive\^^L
-  \let^^L = \relax
-  \gdef\@setuplisting{%
-     \uncatcodespecials
-     \obeywhitespace
-     \makeactive\`
-     \makeactive\^^I
-     \makeactive\^^L
-     \def^^L{\vfill\break}%
-     \parskip = 0pt
-     \listingfont
-  }%
-}%
-\def\listingfont{\tt}%
-%
-% Give definitions to the characters we want to be special.
-% 
-% Do ` separately, so can use ` in the \catcode commands elsewhere.
-% 
-{%
-   \makeactive\`
-   \gdef`{\relax\lq}% Defeat ligatures.
-}%
-{%
-   \makeactive\^^I
-   \gdef^^I{\hskip8\fontdimen2\font \relax}%
-}%
-%
-% 
-% \verbatim ... |endverbatim typesets the ... in typewriter.  To produce a |
-% in the ..., use ||.  This macro was contributed by beebe@math.utah.edu.
-% Generalized to characters other than | by dorai@cs.rice.edu.
-% 
-\def\verbatimescapechar#1{%
-  \gdef\@makeverbatimescapechar{%
-    \@makeverbatimdoubleescape #1%
-    \catcode`#1 = 0
-  }%
-}%
-\def\@makeverbatimdoubleescape#1{%
-  \catcode`#1 = \other
-  \begingroup
-    \lccode`\* = `#1%
-    \lowercase{\endgroup \ece\def*{*}}%
-}%
-\verbatimescapechar\|  % initially escapechar is |
-%
-\def\verbatim{\begingroup
-  \uncatcodespecials
-  \makeactive\` % make space character a single space, not stretchable
-  \@makeverbatimescapechar
-  \tt\obeywhitespace}
-\let\endverbatim = \endgroup
-% 
-% 
-% 
-%  Table of contents, list of figures, etc.
-% 
-% Entries for the table of contents are recorded in \jobname.toc, which
-% we open for writing at the first \writetocentry.  Actually, we use
-% \tocfilebasename for the root of the filename to read; \jobname is
-% the default.
-%
-\def\definecontentsfile#1{%
-  \ece\innernewwrite{#1file}%
-  \ece\innernewif{if@#1fileopened}%
-  \ece\let{#1filebasename} = \jobname
-  \ece\def{open#1file}{\opencontentsfile{#1}}%
-  \ece\def{write#1entry}{\writecontentsentry{#1}}%
-  \ece\def{writenumbered#1entry}{\writenumberedcontentsentry{#1}}%
-  \ece\innernewif{ifrewrite#1file} \csname rewrite#1filetrue\endcsname
-  \ece\def{read#1file}{\readcontentsfile{#1}}%
-}%
-% 
-% We provide \opentocfile, \readtocfile, etc., by default.
-\definecontentsfile{toc}%
-%
-% And `toc' is just the argument to this macro.
-\def\opencontentsfile#1{%
-  \csname if@#1fileopened\endcsname \else
-     \ece{\immediate\openout}{#1file} = \csname #1filebasename\endcsname.#1
-     \ece\global{@#1fileopenedtrue}%
-  \fi
-}%
-%
-% \writetocentry#1#2 produces a line in the .toc file that
-% looks like:
-% \toc#1entry{#2}{page number}
-% e.g., 
-% \tocchapterentry{Introduction}{2}
-% would be written by
-% \writetocentry{chapter}{Introduction}
-% if the chapter started on page two.
-% 
-% Thus, #1 is intended to be something like `chapter' or `section', #2
-% to be the text of the title.
-% 
-% Of course, if you want, you can \write\tocfile yourself with whatever
-% you like.  In that case, you must also call \opentocfile.
-% 
-% By the way, it would be wrong to put a \percentchar at the end of the
-% output line.  Then, when the .toc file is read, if each line is turned
-% into a \leftline, say, there would be no legal breakpoint between the
-% boxes, and one extremely long line would result.
-% 
-% `toc' is the first argument to this; \writetocentry is defined by
-% \definecontentsfile.
-\def\writecontentsentry#1#2#3{\writenumberedcontentsentry{#1}{#2}{#3}{}}%
-%
-% Sometimes you want the control sequence to take another number (e.g.,
-% a chapter number) as a parameter.  (Although you can pass anything you
-% want as the third parameter, naturally.)  The third parameter is
-% expanded at the point of the \writenumberedtocentry, not when the
-% \write actually happens.  This makes the usual case---the third
-% parameter being \the\someregister---work.
-% 
-% For example:
-% \writenumberedtocentry{chapter}{The second chapter}{2}
-% would produce:
-% \tocchapterentry{The second chapter}{2}{14}
-% 
-% if the second chapter started on page 14.
-% 
-% `toc' is the first argument, as above.
-\def\writenumberedcontentsentry#1#2#3#4{%
-  \csname ifrewrite#1file\endcsname
-    \csname open#1file\endcsname
-    \toks0 = {\expandafter\noexpand \csname #1#2entry\endcsname}%
-    \def\temp{#3}%
-    %
-    % Usually #4 is just `\the\register', which we want to expand.  But
-    % if it's not a number at all -- e.g., if it's an author's name, we
-    % don't want to expand control sequences for accents and the like.
-    % So we play some games here.
-    \toks2 = \expandafter{#4}%
-    \edef\cs{\the\toks2}%
-    \edef\@wr{%
-      \write\csname #1file\endcsname{%
-        \the\toks0 % the \toc...entry control sequence
-        {\sanitize\temp}% the text
-        \ifx\empty\cs\else {\sanitize\cs}\fi % A secondary number, or nothing:
-        {\noexpand\folio}% the page number
-      }%
-    }%
-    \@wr
-  \fi
-  \ignorespaces
-}%
-% 
-% The entries are read in when the user invokes \readtocfile (which
-% should be before the first \writetocentry).  We do not open the .toc
-% file to allow reading it in twice to make a short contents or some
-% such.  This should not cause any problems because each of
-% \writecontentsentry and \writenumberedcontentsentry open the .toc
-% file for writing (i.e., empty it) before trying to write to it.
-\def\readcontentsfile#1{%
-   \edef\temp{%
-     \noexpand\testfileexistence[\csname #1filebasename\endcsname]{#1}%
-   }\temp
-   \if@fileexists
-      \input \csname #1filebasename\endcsname.#1\relax
-   \fi
-}%
-%
-% Here are some sample definitions of the \toc...entry macros.  Perhaps
-% you or your book designer can come up with a better way of handling
-% contents than leaders.  These definitions are just examples, not
-% something you might want to actually use to print a document.
-\def\tocchapterentry#1#2{\line{\bf #1 \dotfill\ #2}}%
-\def\tocsectionentry#1#2{\line{\quad\sl #1 \dotfill\ \rm #2}}%
-\def\tocsubsectionentry#1#2{\line{\qquad\rm #1 \dotfill\ #2}}%
-%
-% 
-% 
-%  Cross-references.
-% 
-% Definitions of references are recorded in \jobname.aux, called
-% \auxfile in the macros, which btxmac.tex has opened.
-% 
-% When a label isn't defined, we only want to complain if
-% \xrefwarningtrue; btxmac uses \if@citewarning for this, so we have to
-% reuse that name.  We can't just say \let\ifxrefwarning =
-% \if@citewarning, since then changes to the latter won't be reflected
-% in the former.  On the other hand, we have to have a true \if...
-% command, so \if's and \fi's match properly.  What a mess.
-%
-\let\ifxrefwarning = \iftrue
-\def\xrefwarningtrue{\@citewarningtrue \let\ifxrefwarning = \iftrue}%
-\def\xrefwarningfalse{\@citewarningfalse \let\ifxrefwarning = \iffalse}%
-%
-% 
-% \xref{foo} produces ``p.\thinspace <page#>''.  \xrefn{foo} produces
-% ``<page#>''.  \xrdef{foo} produces nothing, but defines the label
-% `foo' to be on the current page.
-%
-% As usual, it takes two passes to get the cross-references right.  I
-% would like to check for labels being defined twice, but I don't know
-% how to do that.  If the cross-reference file has been read in, many
-% cross-references will be defined that I don't want to complain about.
-% It is only if two \xrdef commands are given to the same string that I
-% want to complain.  I could define a new control sequence for each
-% cross-reference, and check that, but that seems like too high of a
-% price to pay.
-%
-% 
-% \xrlabel{LABEL} expands to a cross-reference internal name.  We append
-% an _ character to NAME, to help avoid conflicts.  And we append an `x'
-% so that we don't redefine \_ on an empty label.
-% 
-\begingroup
-  % Mike Spivak's MathTime macros for Times Roman fonts changes the
-  % catcode of _ to be active. Undo that. (From adam@symcom.math.uiuc.edu.)
-  \catcode`\_ = 8
-  \gdef\xrlabel#1{#1_x}%
-\endgroup
-%
-%
-% \xrdef{LABEL} defines LABEL to be the current page number.  But we
-% don't define the label here, because the page number might be off: if
-% this is not the first time through, the label would already be
-% defined, and we would redefine it with the wrong information.
-% 
-\def\xrdef#1{%
-  \begingroup
-    % Define hyperlink destination.
-    \hldest@impl{xrdef}{#1}%
-    % Define cross-reference but not hyperlink destination.
-    \begingroup
-      \@@hldestoff
-      \definexref{#1}{\noexpand\folio}{page}%
-    \endgroup
-  \endgroup
-}%
-%
-% \definexref{LABEL}{DEFINITION}{CLASS} defines a cross-reference named
-% LABEL of label class CLASS to be DEFINITION.  (Or LABEL can be a
-% control sequence; it's expanded to get the label text.)  To get a
-% possible page number right, we have to write the definition out to the
-% auxiliary file, instead of only defining it directly.
-% 
-\def\definexref#1#2#3{%
-  % Define a hyperlink destination LABEL.
-  \hldest@impl{definexref}{#1}%
-  % Remember what we're given; it might be `\@optionalarg', which
-  % \readauxfile trashes.  (No loss of generality here, since \csname
-  % will fully expand the label anyway.)
-  \edef\temp{#1}%
-  %
-  % Be sure we've read the aux file before we zap it:
-  \readauxfile
-  %
-  % When we read in the aux file next time, define the label:
-  \edef\@wr{\noexpand\writeaux{\string\@definelabel{\temp}{#2}{#3}}}%
-  \@wr
-  \ignorespaces
-}%
-%
-% \@definelabel{LABEL}{DEFINITION}{CLASS} actually defines LABEL of
-% label class CLASS to be DEFINITION.
-% 
-\def\@definelabel#1#2#3{%
-  % Define the control sequence.
-  \expandafter\gdef\csname\xrlabel{#1}\endcsname{#2}%
-  %
-  % Remember what kind of label this is, so \ref will know what to do.
-%  \global\setproperty{\xrlabel{#1}}{class}{#3}%
-  \setpropertyglobal{\xrlabel{#1}}{class}{#3}%
-}%
-%
-% \reftie is used by several cross-referencing macros to separate
-% optional text from label reference.  \refspace is used by \ref to
-% separate optional text from \CLASSword and by \xref to separate
-% optional text from `p. '.
-%
-\def\reftie{\penalty\@M \ }% Do not rely on `~' being defined as a tie.
-\let\refspace\ 
-% 
-% Typeset a reference to the label #1.  If optional argument is
-% present it will be tied with \reftie to the reference and become
-% part of the hyperlink.
-% 
-\def\xrefn{\@getoptionalarg\@finxrefn}%
-\def\@finxrefn#1{%
-  % Hyperlink and optional TEXT.
-  \hlstart@impl{ref}{#1}%
-  \ifx\@optionalarg\empty \else
-    % Save \@optionalarg before it is trashed by \readauxfile.
-    \let\@xrefnoptarg\@optionalarg
-    % Read .aux file -- \@optionalarg may contain cross-references.
-    \readauxfile
-    % Typeset the \@optionalarg
-    {\@@hloff\@xrefnoptarg}\reftie
-  \fi
-  % Typeset the reference.
-  \plain@xrefn{#1}%
-  \hlend@impl{ref}%
-}%
-% This is equivalent to \xrefn but without the hyperlink stuff and the
-% optional parameter so that its expansion does not contain the many
-% \let's, \def's and such which the expansion of \xrefn contains.  It
-% is needed by \eqdefn and \eqsubdefn to be able to `cleanly' write
-% texts of equation labels to .aux file.  It is also used when
-% functionality of \xrefn is needed without the hyperlink and the
-% optional parameter.
-\def\plain@xrefn#1{%
-  \readauxfile
-  %
-  \expandafter \ifx\csname\xrlabel{#1}\endcsname\relax
-    \if@citewarning
-       \message{\linenumber Undefined label `#1'.}%
-    \fi
-    %
-    % Give it a dummy definition, though, to stop multiple error messages.
-    \expandafter\def\csname\xrlabel{#1}\endcsname{%
-      `{\tt
-        \escapechar = -1
-        \expandafter\string\csname#1\endcsname
-      }'%
-    }%
-  \fi
-  \csname\xrlabel{#1}\endcsname % Always produce something.
-}%
-%
-% \refn is just a synonym.
-% 
-\let\refn = \xrefn
-%
-% One common case: print `p. ' before the page number.
-% 
-\def\xrefpageword{p.\thinspace}%
-%
-\def\xref{\@getoptionalarg\@finxref}%
-\def\@finxref#1{%
-  % Hyperlink and optional TEXT.
-  \hlstart@impl{xref}{#1}%
-  \ifx\@optionalarg\empty \else
-    {\@@hloff\@optionalarg}\refspace
-  \fi
-  % Typeset page reference but omit hyperlink.
-  \xrefpageword\plain@xrefn{#1}%
-  \hlend@impl{xref}%
-}%
-%
-% \ref[TEXT]{LABEL} typesets TEXT, \CLASSword for LABEL's class (if it's defined)
-% and then does \refn on LABEL. But amstex also has a \ref, so tell the
-% user if they try to use \ref and have loaded amsppt.sty.
-% 
-% \refs{LABEL} is similar, but puts the letter `s' after the \...word, thus
-% producing (for example) `Figures 1.2' (presumably to be followed by
-% `and~\refn{fig-1.3}').
-% 
-% Note that \ref takes an optional TEXT, while \refs does not.  This
-% text (together with \CLASSword) will become part of the hyperlink
-% generated by \ref.  \refs does not include \CLASSword in the
-% hyperlink.
-%
-\def\@maybewarnref{%
-  \ifundefined{amsppt.sty}%
-    % No amsppt.sty, so just use ours.
-  \else
-    \message{Warning: amsppt.sty and Eplain both define \string\ref. See
-             the Eplain manual.}%
-    % Remember their definition.
-    \let\amsref = \ref
-  \fi
-  \let\ref = \eplainref
-  \ref
-}
-\let\ref = \@maybewarnref
-%
-\def\eplainref{\@getoptionalarg\@fineplainref}%
-\def\@fineplainref{\@generalref{1}{}}%
-\def\refs{\let\@optionalarg\empty \@generalref{0}s}%
-%
-% #1 is an integer flag which tells whether hyperlink should include
-% \@optionalarg and class word (non-0) or not (0).  #2 is the text to
-% follow the \...word.  Both #1 and #2 are supplied by the macros
-% above.  #3 comes from the document, and is the LABEL.
-%
-% \reftie separates \@optionalarg or \..word from \refn; \refspace
-% separates \@optionalarg from \..word.
-%
-\def\@generalref#1#2#3{%
-  % Save \@optionalarg before it is trashed by \readauxfile.
-  \let\@generalrefoptarg\@optionalarg
-  \readauxfile
-  % Maybe start hyperlink here.
-  \ifcase#1 \else \hlstart@impl{ref}{#3}\fi
-  % Get the class of the label.
-  \edef\temp{\getproperty{\xrlabel{#3}}{class}}%
-  % If the word for this class is not defined, don't complain.
-  \expandafter\ifx\csname \temp word\endcsname\relax
-    % Produce \@optionalarg followed by a \reftie, if \@optionalarg is
-    % not empty.
-    \ifx\@generalrefoptarg\empty \else {\@@hloff\@generalrefoptarg\reftie}\fi
-  \else
-    \begingroup
-      \@@hloff
-      % Produce \@optionalarg, if not empty, followed by a \refspace.
-      \ifx\@generalrefoptarg\empty \else \@generalrefoptarg \refspace \fi
-      % Produce the word.
-      \csname \temp word\endcsname
-      % Add the suffix and then put in a \reftie before the \refn.
-      #2\reftie
-    \endgroup
-  \fi
-  % Maybe start hyperlink here.
-  \ifcase#1 \hlstart@impl{ref}{#3}\fi
-  % Typeset the reference omitting hyperlinks.
-  \plain@xrefn{#3}%
-  \hlend@impl{ref}%
-}%
-%
-%
-% References to equations are similar.
-%
-% \eqref{foo} produces ``(<text for equation label foo>)''.
-% \eqdefn{foo} advances \eqnumber, resets \eqsubnumber, and defines
-%   `foo' to be the new number. 
-% \eqsubdefn{foo} advances \eqsubnumber and defines `foo'.  \eqref works
-%   for both equations and subequations,
-% \eqdef{foo} does \eqdefn, then inserts an \eqno and \eqref.
-% \eqsubdef{foo} does \eqsubdefn, then what \eqdef does.
-% 
-% The non-``sub'' macros also take an optional argument; if it's
-% present, we use it as the text for the equation label, instead of the
-% various counters.
-%
-% Because there are no page break issues with equations, we can
-% immediately define the control sequence.  But we also need to write
-% the definition out, in case the user wants to forward reference an
-% equation (bad style as that may be).
-%
-% The current equation number is in \eqnumber; we just advance it by one
-% for each \eqdef.  You can handle fancier equation numbers (e.g., ones
-% that include a chapter number) by redefining \eqprint, below, and
-% using your own counters.  We do provide for one level of substructure,
-% since that's more painful to implement than superstructures.
-%
-\newcount\eqnumber
-\newcount\subeqnumber
-%
-%
-% \eqdefn[TEXT]{LABEL} defines LABEL to be TEXT (if it's present),
-% otherwise it advances \eqnumber and defines LABEL to be that.  It
-% doesn't produce anything.
-% 
-\def\eqdefn{\@getoptionalarg\@fineqdefn}%
-\def\@fineqdefn#1{%
-  \ifx\@optionalarg\empty
-    \global\advance\eqnumber by 1
-    % We call \eqconstruct here instead of in \@eqdefn because we don't
-    % want to expand it for \eqsubdefn -- \eqsubdefn already includes an
-    % \eqrefn which includes the text of the label which was \eqconstructed.
-    \def\temp{\eqconstruct{\number\eqnumber}}%
-  \else
-    % In the next \def there is (I believe) a spurious \noexpand. 
-    % I leave in the old definition, albeit commented out, in case the
-    % \noexpand really _is_ necessary. But I don't thikn so. Adam Lewenberg
-%    \def\temp{\noexpand\@optionalarg}%
-    \def\temp{\@optionalarg}% 
-  \fi
-  %
-  % Always reset the current subequation number:
-  \global\subeqnumber = 0
-  %
-  % Remember this label, so that we can define subequations:
-  \gdef\@currenteqlabel{#1}%
-  \toks0 = \expandafter{\@currenteqlabel}%
-  %
-  % Actually do the definition, replacing \xrefn and \eqrefn with
-  % \plain@xrefn and taking precautions not to expand \plain@xrefn
-  % in what we output to the aux file.  \plain@xrefn expands to many things,
-  % including \count@'s and \edef's and the expansion of \xrlabel, and
-  % it's just a real mess.
-  \begingroup
-    \def\eqrefn{\noexpand\plain@xrefn}%
-    \def\xrefn{\noexpand\plain@xrefn}%
-    \edef\temp{\noexpand\@eqdefn{\the\toks0}{\temp}}%
-    \temp
-  \endgroup
-}%
-% 
-% 
-% \eqsubdefn defines its argument as a ``subequation'' of the last \eqdef.
-%
-\def\eqsubdefn#1{%
-  \global\advance\subeqnumber by 1
-  \toks0 = {#1}%
-  %
-  % Get the text of the label;
-  \toks2 = \expandafter{\@currenteqlabel}%
-  %
-  % We must expand \@currenteqlabel.  We have to not expand
-  % \eqsubreftext here, as well as \plain@xrefn (which we substitute
-  % for \eqrefn and \xrefn), since the first arg to \eqsubreftext
-  % could also include lots of complicated things.
-  \begingroup
-    \def\eqrefn{\noexpand\plain@xrefn}%
-    \def\xrefn{\noexpand\plain@xrefn}%
-    \def\eqsubreftext{\noexpand\eqsubreftext}%
-    \edef\temp{%
-      \noexpand\@eqdefn
-        {\the\toks0}%
-        {\eqsubreftext{\eqrefn{\the\toks2}}{\the\subeqnumber}}%
-    }%
-    \temp           
-  \endgroup
-}%
-% 
-% \@eqdefn{LABEL}{REF-TEXT} actually handles the equation number
-% definitions and writing to the aux file.
-% 
-% In contrast to \xrdef, we define LABEL right away (as REF-TEXT).  We
-% can do this since we know right now what the right equation number is.
-% This eliminates some unnecessary warning.  It also lets the user put
-% \eqdef{} on all equations and have it work, since then \eqref
-% refers to the just-defined new value.
-% 
-\def\@eqdefn#1#2{%
-  % Define hyperlink destination taking care of empty LABEL.
-  \hl@define@eqlabel{#1}%
-  \hldest@impl{eq}{\hl@eqlabel}%
-  % Define cross-reference but not hyperlink destination.
-  \begingroup
-    \@@hldestoff
-    \definexref{#1}{#2}{eq}%
-  \endgroup
-  % Define the LABEL.
-  \@definelabel{#1}{#2}{eq}%
-}%
-% 
-% \eqdef{LABEL} defines LABEL, with \eqdefn, then prints it.  We allow
-% an optional argument to explicitly specify the text which we define
-% the label as.
-%
-\def\eqdef{\@getoptionalarg\@fineqdef}%
-\def\@fineqdef{%
-  \toks0 = \expandafter{\@optionalarg}%
-  \edef\temp{\noexpand\@eqdef{\noexpand\eqdefn[\the\toks0]}}%
-  \temp
-}%
-%
-% \eqsubdef is to \eqdef as \eqsubdefn is to \eqdefn.  No optional
-% argument allowed here.
-% 
-\def\eqsubdef{\@eqdef\eqsubdefn}%
-%
-% \@eqdef{DEFN-CMD}{LABEL} defines LABEL, using DEFN-CMD.  Then it
-% inserts an \eqno (unless it's called when an \eqno would be invalid).
-% Then it prints the newly-defined value using \eqprint.
-% 
-\def\@eqdef#1#2{%
-  % Define the label but not hyperlink destination (we want to define
-  % the destination after \eqno).  Note that \@eqdefn will call
-  % \hl@define@eqlabel{#2}, so we won't call it again (definintions in
-  % \hl@define@eqlabel must be global to survive past the group).
-  \begingroup
-    \@@hldestoff
-    #1{#2}%
-  \endgroup
-  % Define hyperlink destination and print the text.
-  \@maybedisableeqno
-  \eqno % \hl@define@eqlabel already called in \@eqdefn.
-        \hldest@impl{eq}{\hl@eqlabel}%
-        \let\@optionalarg\empty % \@fineqref will examine \@optionalarg.
-        {\@@hloff\@fineqref{#2}}% No hyperlink here.
-  \@mayberestoreeqno
-  \ignorespaces
-}%
-% 
-% 
-% If we are in an alignment or some other inner place, \eqno won't work.
-% 
-\let\@mayberestoreeqno = \relax
-%
-\def\@maybedisableeqno{%
-  \ifinner
-    \global\let\eqno = \relax
-    \global\let\@mayberestoreeqno = \@restoreeqno
-  \fi
-}%
-%
-% This makes `\eqno' mean \eqno again.
-% 
-\let\@primitiveeqno = \eqno
-\def\@restoreeqno{%
-  \global\let\eqno = \@primitiveeqno
-  \global\let\@mayberestoreeqno = \empty
-}%
-%
-% 
-% \eqrefn[TEXT]{LABEL} produces the text for the equation label LABEL, or
-% something suitable if LABEL is undefined.  (It possibly issues a
-% warning in the latter case as well.)  TEXT followed by a \reftie is
-% prepended to the equation text as part of the hyperlink.
-%
-\def\eqrefn{\@getoptionalarg\@fineqrefn}%
-\def\@fineqrefn#1{%
-  \eqref@start{#1}%
-  % Typeset the equation reference but do not produce hyperlink.
-  \plain@xrefn{#1}%
-  \hlend
-}%
-%
-% \eqref[TEXT]{LABEL} is the usual way to refer to equation labels; it
-% calls \eqprint on the text of LABEL, prepending it with TEXT and a
-% \reftie as part of the hyperlink.
-% 
-\def\eqref{\@getoptionalarg\@fineqref}%
-\def\@fineqref#1{%
-  \eqref@start{#1}%
-  % Typeset the equation reference but do not produce hyperlink.
-  \eqprint{\plain@xrefn{#1}}%
-  \hlend@impl{eq}%
-}%
-% Common code executed at the start of \@fineqrefn and \@fineqref.
-\def\eqref@start#1{%
-  % Save \@optionalarg in case \phantomeqlabel is redefined by the
-  % user to something that trashes it.
-  \let\@eqrefoptarg\@optionalarg
-  % Hyperlink (fetch last `phantom' equation label if LABEL is empty).
-  \ifempty{#1}%
-    \hlstart@impl{eq}{\phantomeqlabel}%
-  \else
-    \hlstart@impl{eq}{#1}%
-  \fi
-  % Optional TEXT followed by a \reftie.
-  \ifx\@eqrefoptarg\empty \else
-    {\@@hloff\@eqrefoptarg\reftie}%
-  \fi
-}%
-%
-% 
-% \eqconstruct{EQ-TEXT} constructs an equation number, i.e., the text to
-% be defined as the value of a label.
-% 
-\let\eqconstruct = \identity
-%
-% \eqprint{EQ-TEXT} produces the typeset equation number EQ-TEXT.
-%
-\def\eqprint#1{(#1)}%
-%
-% \eqsubreftext{EQ-TEXT}{SUBEQ-TEXT} produces the text of a subequation
-% reference.  (\eqprint is later called on the result of this to produce
-% output for subequations; I didn't define any \subeqprint.)
-% 
-\def\eqsubreftext#1#2{#1.#2}%
-%
-%
-% 
-%  Indexing.
-% 
-% \defineindex{PREFIX} defines an index with ``prefix'' PREFIX.  The
-% prefix is used to construct the output filename and the various
-% commands.  We just define all the index commands for this index to
-% call the general commands with PREFIX.
-%
-\let\extraidxcmdsuffixes = \empty
-%
-\outer\def\defineindex#1{%
-  \def\@idxprefix{#1}%
-  %
-  % Define the indexing commands for this prefix. 
-  \for\@idxcmd:=,marked,submarked,name%
-                \extraidxcmdsuffixes\do
-  {%
-    \@defineindexcmd\@idxcmd
-  }%
-  %
-  % Allocate a stream for the output.
-  \ece\innernewwrite{@#1indexfile}%
-  %
-  % And a conditional to test whether we've opened the file.
-  \ece\innernewif{if@#1indexfileopened}%
-}%
-%
-%
-% \@defineindexcmd{SUFFIX} defines both silent and non-silent index
-% command for prefix \@idxprefix with suffix SUFFIX.  That is, we define
-% both `\@idxprefix dxSUFFIX' and `\s\@idxprefix dxSUFFIX' to call the
-% corresponding generic command with \@idxprefix.  \silentindexentry is
-% used to decide whether we should ignore following spaces.
-% 
-\newif\ifsilentindexentry
-%
-\def\@defineindexcmd#1{%
-  \@defineoneindexcmd{s}{#1}\silentindexentrytrue
-  \@defineoneindexcmd{}{#1}\silentindexentryfalse
-}%
-%
-%
-% \@defineoneindexcmd{PREFIX}{SUFFIX}{PRECALL} does just one silent or
-% non-silent commands.  We define the command `\@@PREFIXidxSUFFIX' to do
-% PRECALL, then define \@idxprefix, then call \@idxgetrange with an
-% argument of `\@@{,s}idxSUFFIX'.  (So far every indexing command 
-% should allow a range.  If not, you could redefine `\@@{,s}idxSUFFIX'
-% after this macro is called.)
-% 
-\def\@defineoneindexcmd#1#2#3{%
-  \toks@ = {#3}%
-  \edef\temp{%
-    \def
-      % We have to restrict expansion because the generic (\@@...)
-      % commands will be defined after the first call to \defineindex.
-      % Not expanding the user (\idx...) commands is unnecessary unless
-      % the user has defined some new commands, but may as well be cautious.
-      \expandonce\csname#1\@idxprefix dx#2\endcsname % e.g., \idx or \sidxname.
-      {\def\noexpand\@idxprefix{\@idxprefix}% define \@idxprefix
-       % call, e.g., \@@idx or \@@sidxname:
-       \expandonce\csname @@#1idx#2\endcsname
-      }%
-    \def
-      \expandonce\csname @@#1idx#2\endcsname{% e.g., \@@idx
-        % First do PRECALL.
-        \the\toks@
-        % Then call \@idxgetrange with, e.g., \@idx or \@sidxname as its arg.
-        \noexpand\@idxgetrange\expandonce\csname @#1idx#2\endcsname
-      }%
-  }%
-  \temp
-}%
-%
-%
-% \@idxwrite{TERM}{PAGENO} writes a general index entry for TERM on page
-% PAGENO to the index file `\@idxprefix indexfile'.  We open the stream
-% as `\indexfilebasename.\@idxprefix dx' if it isn't already open.
-%
-\let\indexfilebasename = \jobname
-%
-\def\@idxwrite#1#2{%
-  % Be sure the file is opened.
-  \csname if@\@idxprefix indexfileopened\endcsname \else
-    \expandafter\immediate\openout\csname @\@idxprefix indexfile\endcsname =
-      \indexfilebasename.\@idxprefix dx
-    \expandafter\global\csname @\@idxprefix indexfileopenedtrue\endcsname
-  \fi
-  %
-  % Save the index term.
-  \def\temp{#1}%
-  %
-  % Write the index term and page number.
-  \edef\@wr{%
-    \expandafter\write\csname @\@idxprefix indexfile\endcsname{%
-      \string\indexentry
-      {\sanitize\temp}%
-      {\noexpand#2}%
-    }%
-  }%
-  \@wr
-  % 
-  % Marginalize the index term, if desired.
-  % (the \allowhyphens allows `infinitesimal' in \sidx{Infinitesimal}infinitesimal 
-  % to be hyphenated.
-  \ifindexproofing \insert\@indexproof{\indexproofterm{#1}}\allowhyphens\fi
-  %
-  % We just appended at least one non-discardable item (namely, the
-  % whatsit from the \write) to the current list.  So in case glue comes
-  % next (not unlikely), be sure we don't inadvertently make that glue a
-  % valid breakpoint, if it wouldn't have been without us.
-  \hookrun{afterindexterm}%
-  %
-  % This is the end of the index entry processing.  If this was a silent
-  % entry, ignore following spaces.
-  \ifsilentindexentry \expandafter\ignorespaces\fi
-}%
-%
-%
-% If this conditional is true, we output the index terms on the page
-% where they occur.
-\newif\ifindexproofing
-%
-% We need a new insertion class to collect the proofed terms.
-\newinsert\@indexproof
-\dimen\@indexproof = \maxdimen                  % No limit on number of terms.
-\count\@indexproof = 0  \skip\@indexproof = 0pt % They take up no space.
-%
-% This actually typesets the proofed term.  We don't go to any lengths
-% to provide nice-looking output; since the term might have all kinds of
-% weird characters in it, we just dump it in the smallest standard
-% Computer Modern typewriter font.
-% 
-% We put the term in an \hbox, even though that might make the output
-% run off the page, since we don't really need to see all of it, and
-% I think it's better to opt for simplicity -- one term per line.
-\font\indexprooffont = cmtt8
-\def\indexproofterm#1{\hbox{\strut \indexprooffont #1}}%
-%
-%
-% If \output doesn't use \makeheadline, or redefines it, it's up to the
-% new \output to define index hyperlink destination and to call
-% \indexproofunbox.
-\let\@plainmakeheadline = \makeheadline
-\def\makeheadline{%
-  % Define index page destination only when this `cross-reference' is defined.
-  \expandafter\ifx\csname\xrlabel{\idxpagexref{\folio}}\endcsname\relax \else
-    % Say \@@hldeston in case a page break happened at an unfortunate
-    % time when user said \hldestoff.
-    {\@@hldeston \hldest@impl{idx}{\hlidxpagelabel{\folio}}}%
-  \fi
-  \indexproofunbox
-  \@plainmakeheadline
-}%
-%
-% We want to put the proof index terms in the margin, outside the
-% printed area. So if \outsidemargin (for odd pages) and \insidemargin
-% (for even pages) are undefined, we define them (both) to be the default
-% TeX margin -- one inch + \hoffset.
-\def\indexsetmargins{%
-  \ifx\undefined\outsidemargin
-    \dimen@ = 1truein
-    \advance\dimen@ by \hoffset
-    \edef\outsidemargin{\the\dimen@}%
-    \let\insidemargin = \outsidemargin
-  \fi
-}%
-%
-% We always put the terms in the right-hand margin, so long terms run
-% off the page, instead of into the text.
-\def\indexproofunbox{%
-  \ifvoid\@indexproof\else
-    \indexsetmargins
-    \rlap{%
-      \kern\hsize
-      \ifodd\pageno \kern\outsidemargin \else \kern\insidemargin \fi
-      \vbox to 0pt{\unvbox\@indexproof\vss}%
-    }\nointerlineskip
-  \fi
-}%
-%
-%
-% \@idxgetrange\CS parses an optional argument which, if present, should
-% be either `begin' or `end', marking the beginning or ending of a range
-% for the index entry.  If we find this, we set the appropriate one of
-% \@idxrangestr.  Then we call \CS.
-% 
-% If the optional argument is `see' or `seealso' we read another
-% argument, namely, the entry to see.
-% 
-\def\idxrangebeginword{begin}%
-\def\idxbeginrangemark{(}% the corresponding magic char to go in the idx file
-%
-\def\idxrangeendword{end}%
-\def\idxendrangemark{)}%
-%
-\def\idxseecmdword{see}%
-\def\idxseealsocmdword{seealso}%
-\newif\if@idxsee
-\newif\if@hlidxencap
-\let\@idxseenterm = \relax
-%
-\def\idxpagemarkupcmdword{pagemarkup}%
-\let\@idxpagemarkup = \relax
-%
-\def\@idxgetrange#1{%
-  \let\@idxrangestr = \empty
-  \let\@afteridxgetrange = #1%
-  \@getoptionalarg\@finidxgetopt
-}%
-\def\@finidxgetopt{%
-  \@hlidxencaptrue
-  %
-  \for\@idxarg:=\@optionalarg\do{%
-    % These are ordered by my guess at frequency of use.
-    \expandafter\@idxcheckpagemarkup\@idxarg=,%
-    %
-    \ifx\@idxarg\idxrangebeginword
-      \def\@idxrangestr{\idxencapoperator\idxbeginrangemark}%
-    \else
-      \ifx\@idxarg\idxrangeendword
-        \def\@idxrangestr{\idxencapoperator\idxendrangemark}%
-        \@hlidxencapfalse
-      \else
-        \ifx\@idxarg\idxseecmdword
-          \def\@idxpagemarkup{indexsee}%
-          \@idxseetrue
-          \@hlidxencapfalse
-        \else
-          \ifx\@idxarg\idxseealsocmdword
-            \def\@idxpagemarkup{indexseealso}%
-            \@idxseetrue
-            \@hlidxencapfalse
-          \else
-             \ifx\@idxpagemarkup\relax
-               \errmessage{Unrecognized index option `\@idxarg'}%
-             \fi
-          \fi
-        \fi
-      \fi
-    \fi
-  }%
-  % Stick hyperlink encapsulator into \@idxpagemarkup.
-  \ifnum\hldest@place@idx < 0 \else
-    \if@hlidxencap
-      \ifx\@idxpagemarkup\relax
-        % Even when user gives no pagemarkup command, we still do
-        % insert our hyperlink encapsulator.
-        \let\@idxpagemarkup\empty
-      \fi
-      \ifcase\hldest@place@idx \relax
-        % \hldest@place@idx = 0, dests point to a page with a term.
-        \edef\@idxpagemarkup{hlidxpage{\@idxpagemarkup}}%
-        % We want to define index \hldest's only on those
-        % pages which contain at least one index term, so this
-        % `cross-reference' will tell \makeheadline on which pages to
-        % generate an \hldest.
-        {\@@hldestoff \definexref{\idxpagexref{\folio}}{}{}}%
-      \else
-        % \hldest@place@idx = 1, dests point to exact location of a term.
-        \global\advance\hlidxlabelnumber by 1
-        \edef\@idxpagemarkup{hlidx{\hlidxlabel}{\@idxpagemarkup}}%
-        \hldest@impl{idx}{\hlidxlabel}%
-      \fi
-    \fi
-  \fi
-  %
-  \@afteridxgetrange
-}%
-%
-%
-% Check for a command of the form `pagemarkup=\cmd', and if found, set
-% \@idxpagemarkup to `cmd'.
-% 
-\def\@idxcheckpagemarkup#1=#2,{%
-  \def\temp{#1}%
-  \ifx\temp\idxpagemarkupcmdword
-    \if ,#2, % If #2 is empty, complain.
-      \errmessage{Missing markup command to `pagemarkup'}%
-    \else
-      % Remove a trailing =.
-      \def\temp##1={##1}%
-      \edef\@idxpagemarkup{\temp\string#2}%
-    \fi
-  \fi
-}%
-%
-%
-% \hlidxpage and \hlidx are hyperlink encapsulators for the two types
-% of hyperlink destinations for index terms.
-%
-% \hldest@place@idx defines which type is selected.  When defined to 0,
-% we generate destinations pointing to the page on which the indexed
-% term is located.  When defined to 1, we generate destinations
-% pointing to exact location of the indexed term.  When negative, we
-% generate no hyperlinks / destinations.
-\def\hldest@place@idx{-1}%
-% Name for a `cross-reference' which \makeheadline uses do decide on
-% which pages to generate \hldest.
-\def\idxpagexref#1{@@IDXPG@@#1}%
-% Hyperlink labels for both types of destinations.
-\newcount\hlidxlabelnumber
-\def\hlidxlabel{IDX\the\hlidxlabelnumber}%
-\def\hlidxpagelabel#1{IDXPG#1}%
-%
-% \hlidx{HYPERLINK-LABEL}{PAGEENCAP}{PAGESPEC}
-\def\hlidx#1#2#3{%
-  \hlstart@impl{idx}{#1}%
-  \csname #2\endcsname{#3}%
-  \hlend@impl{idx}%
-}%
-%
-% \hlidxpage{PAGEENCAP}{PAGESPEC}
-%
-% We expect PAGESPEC to be one of the following:
-%   14          (single page number)
-%   14, 15      (list of two consecutive page numbers)
-%   14--15      (page range)
-%
-% If you configure MakeIndex to use different page list separator
-% (delim_n parameter in .mst file) / different page range separator
-% (delim_r parameter), you should call \setidxpagelistdelimiter /
-% \setidxpagerangedelimiter to setup the new separators.
-%
-% In case of a single page number, we call \PAGEENCAP on the page
-% number and turn the result into a hyperlink.
-%
-% In case of a two-page list, we break the list, call \PAGEENCAP on
-% each of the page numbers separately, and turn each result into a
-% hyperlink, producing page list separator between the page numbers.
-%
-% In case of a page range, we do not break the range, call \PAGEENCAP
-% on the entire range and turn what results into a hyperlink for the
-% first of the page numbers.
-\def\hlidxpage#1#2{%
-  % Set \@idxpagei[i][ref] and \@idxpagesep
-  \@hlidxgetpages{#2}%
-  % Alias for \PAGEENCAP.
-  \expandafter\let\expandafter\@idxpageencap\csname #1\endcsname
-  % Now comes the first part, to be done in any of the three cases.
-  \hlstart@impl{idx}{\hlidxpagelabel{\@idxpageiref}}%
-  \expandafter\@idxpageencap\expandafter{\@idxpagei}%
-  \hlend@impl{idx}%
-  % The second part, to be done only if there is a second page number.
-  \ifx\@idxpageii\empty \else
-    \@idxpagesep
-    \hlstart@impl{idx}{\hlidxpagelabel{\@idxpageiiref}}%
-    \expandafter\@idxpageencap\expandafter{\@idxpageii}%
-    \hlend@impl{idx}%
-  \fi
-}%
-%
-% This macro parses PAGESPEC parameter to \hlidxpage.  It sets
-% \@idxpagei to the first page number, \@idxpageii to the second (if
-% present; if not, \@idxpageii will be set to \empty).  For the first
-% page number, use \@idxpageiref to construct hyperlink label; for
-% the second page number, use \@idxpageiiref.  Use \@idxpagesep to
-% separate the two page numbers.
-%
-% NOTE:  we use \@idxpagei[i], not \idxpagei[i], because the user may
-% use \idxparselist / \idxparserange in his \PAGEENCAP, in which case
-% our \idxpagei[i]'s will get garbled.
-\def\@hlidxgetpages#1{%
-  % Try to parse a two-page list.
-  \idxparselist{#1}%
-  \ifx\idxpagei\empty
-    % It is not a two-page list, try page range.
-    \idxparserange{#1}%
-    \ifx\idxpagei\empty
-      % It is neither a two-page list nor a page range, so we assume
-      % it is a single page number.
-      \def\@idxpageiref{#1}% Label for \hlstart.
-    \else
-      % It is a page range.
-      \let\@idxpageiref\idxpagei % Label for \hlstart.
-    \fi
-    \def\@idxpagei{#1}%
-    \let\@idxpageii\empty
-  \else
-    % It is a two-page list.
-    \let\@idxpagei\idxpagei
-    \let\@idxpageii\idxpageii
-    \let\@idxpageiref\idxpagei % Label for \hlstart.
-    \let\@idxpageiiref\idxpageii % Label for \hlstart.
-    \let\@idxpagesep\idxpagelistdelimiter
-  \fi
-}%
-%
-% Set up a macro \@idxparselist and user-accessible \idxparselist for
-% parsing two-page list.  Takes list separator (which is saved in
-% \idxpagelistdelimiter).  If the list is found, \@idxparselist will
-% set \idxpagei to the first page number, \idxpageii to the second;
-% if not found, it will set \idxpagei to \empty (this implies that
-% the list's first page number should never be empty).
-\def\setidxpagelistdelimiter#1{%
-  \gdef\idxpagelistdelimiter{#1}%
-  \gdef\@removepagelistdelimiter##1#1{##1}%
-  \gdef\@idxparselist##1#1##2\@@{%
-    \ifempty{##2}%
-      \let\idxpagei\empty
-    \else
-      \def\idxpagei{##1}%
-      \edef\idxpageii{\@removepagelistdelimiter##2}%
-    \fi
-  }%
-  \gdef\idxparselist##1{\@idxparselist##1#1\@@}%
-}%
-%
-% Same as previous, but \@idxparserange and \idxparserange will parse
-% page range, range separator is saved in \idxpagerangedelimiter.
-\def\setidxpagerangedelimiter#1{%
-  \gdef\idxpagerangedelimiter{#1}%
-  \gdef\@removepagerangedelimiter##1#1{##1}%
-  \gdef\@idxparserange##1#1##2\@@{%
-    \ifempty{##2}%
-      \let\idxpagei\empty
-    \else
-      \def\idxpagei{##1}%
-      \edef\idxpageii{\@removepagerangedelimiter##2}%
-    \fi
-  }%
-  \gdef\idxparserange##1{\@idxparserange##1#1\@@}%
-}%
-%
-% Set up the default delimiters.
-\setidxpagelistdelimiter{, }%
-\setidxpagerangedelimiter{--}%
-%
-%
-% \@idxtokscollect uses \@idxmaintoks as the token list for the main
-% part of an index entry and \@idxsubtoks for the subpart.  Then it
-% calls \@idxwrite.
-% 
-\def\idxsubentryseparator{!}%
-\def\idxencapoperator{|}%
-\def\idxmaxpagenum{99999}%
-%
-\newtoks\@idxmaintoks
-\newtoks\@idxsubtoks
-%
-\def\@idxtokscollect{%
-  % Remember the subentry.
-  \edef\temp{\the\@idxsubtoks}%
-  %
-  % We want to expand the conditions, but not the terms.  The index
-  % entry starts simply with \@idxmaintoks and \@idxsubtoks.
-  \edef\@indexentry{%
-    \the\@idxmaintoks
-    \ifx\temp\empty\else \idxsubentryseparator\the\@idxsubtoks \fi
-    \@idxrangestr
-  }%
-  %
-  % If this is a `see' or `see also' entry, we need to read one more
-  % arg.  We use a giant page number so the entry will be last (for the
-  % benefit of `see also's).  MakeIndex rejects page numbers >=1000.
-  % 
-  \if@idxsee
-    \@idxseefalse % Reset so the next term won't be a `see'.
-    \edef\temp{\noexpand\@finidxtokscollect{\idxmaxpagenum}}%
-  \else
-    \def\temp{\@finfinidxtokscollect\folio}%
-  \fi
-  \temp
-}%
-%
-%
-% \@finidxtokscollect{PAGENO}{REAL-TERM} reads the final term for
-% see/see also entries.  We do not check if the person has put both a
-% range and a see in the same index term (which will confuse makeindex).
-% 
-\def\@finidxtokscollect#1#2{%
-  \def\@idxseenterm{#2}%
-  \@finfinidxtokscollect{#1}%
-}%
-%
-% \@finfinidxtokscollect{PAGENO} writes \@indexentry for page PAGENO.
-% Besides \@indexentry, if \@idxpagemarkup is not \relax we output an
-% index entry \@indexentry|\@idxpagemarkup{PAGENO} (but omitting | if
-% this is a range term, because in that case | will have been added
-% together with \@idxrangestr in \@idxtokscollect).  And if
-% \@idxseenterm is not \relax we output {\@idxseenterm} after the
-% \@idxpagemarkup.  (This will become an argument to the ``markup''
-% command, which will be \indexsee or \indexseealso.)
-% 
-\def\@finfinidxtokscollect#1{%
-  % If we've got a page markup command, append it.
-  \ifx\@idxpagemarkup\relax \else
-    \toks@ = \expandafter{\@indexentry}%
-    \edef\@indexentry{%
-      \the\toks@
-      % Add | only if this is not a range term, otherwise | has
-      % already been added with \@idxrangestr by \@idxtokscollect.
-      \ifx\@idxrangestr\empty \idxencapoperator \fi
-      \@idxpagemarkup
-    }%
-    \let\@idxpagemarkup = \relax
-  \fi
-  %
-  % If we've got an argument to the ``page markup'' command, append it.
-  \ifx\@idxseenterm\relax \else
-    \toks@ = \expandafter{\@indexentry}%
-    \edef\@indexentry{\the\toks@{\sanitize\@idxseenterm}}%
-    \let\@idxseenterm = \relax
-  \fi
-  %
-  % Finally, write what we've constructed.
-  \expandafter\@idxwrite\expandafter{\@indexentry}{#1}%
-}%
-%
-%
-% \@idxcollect{MAIN}{SUB} sets up the token registers
-% \@idx{main,sub}toks, then calls \@idxtokscollect.  This is convenient
-% for some of the macros below.
-% 
-\def\@idxcollect#1#2{%
-  \@idxmaintoks = {#1}%
-  \@idxsubtoks = {#2}%
-  \@idxtokscollect
-}%
-%
-%
-% Following are the TeX macros that correspond to the commands
-% that actually appear in the document.
-%
-% \@idx{TERM} produces TERM in the output and then makes the index entry
-% for TERM as usual.  We don't allow a [SUBTERM] here since then we
-% would lose spaces after the command, which would be very inconvenient.
-%
-% As with all our index commands, we've already defined \@idxprefix (in
-% \idx or whatever), to save passing it around, and we've looked for a
-% range argument before TERM.
-% 
-\def\@idx#1{%
-  #1% Produce TERM as output.
-  \@idxcollect{#1}{}%
-}%
-%
-% \@sidx{TERM}[SUBTERM] produces an index entry TERM and no output.  If
-% SUBTERM is present, this is a subentry.  (At the moment, I don't
-% provide for subsubentries, since I've never needed that.)
-% 
-\def\@sidx#1{\@idxmaintoks = {#1}\@getoptionalarg\@finsidx}%
-\def\@finsidx{%
-  \@idxsubtoks = \expandafter{\@optionalarg}%
-  \@idxtokscollect
-}%
-%
-%
-% \@idxconstructmarked{TOKS-REG}\CS{TERM}
-% 
-\def\idxsortkeysep{@}% This `@' is catcode 11, but it doesn't matter.
-%
-\def\@idxconstructmarked#1#2#3{%
-  \toks@ = {#2}% The control sequence.
-  \toks2 = {#3}% The term.
-  %
-  % Construct TERM@\CS{TERM} as the string to write.
-  \edef\temp{\the\toks2 \idxsortkeysep \the\toks@{\the\toks2}}%
-  %
-  % Save it in TOKS-REG.
-  #1 = \expandafter{\temp}%
-}%
-%
-%
-% \@idxmarked\CS{TERM} outputs \CS{TERM} and then calls the main part of
-% \@sidxmarked.
-%
-\def\@idxmarked#1#2{%
-  #1{#2}% Produce \CS{TERM} as output.
-  \@idxconstructmarked\@idxmaintoks{#1}{#2}%
-  \@idxsubtoks = {}%
-  \@idxtokscollect
-}%
-%
-% \@sidxmarked\CS{TERM}[SUBTERM] outputs an index entry sorted by TERM
-% but producing \CS{TERM}.
-% 
-\def\@sidxmarked#1#2{%
-  \@idxconstructmarked\toks@{#1}{#2}%
-  \edef\temp{{\the\toks@}}%
-  \expandafter\@sidx\temp
-}%
-%
-%
-% \@idxsubmarked{TERM}\CS{SUBTERM} is like \@idxmarked, except that it's
-% SUBTERM that's marked instead of TERM.
-% 
-\def\@idxsubmarked#1#2#3{%
-  #1 #2{#3}% produce `TERM \CS{SUBTERM} as output.
-  \@sidxsubmarked{#1}{#2}{#3}%
-}%
-%
-% \@sidxsubmarked{TERM}\CS{SUBTERM} is to \@sidxmarked as \@idxsubmarked
-% is to \@idxmarked.
-% 
-\def\@sidxsubmarked#1#2#3{%
-  \@idxmaintoks = {#1}%
-  \@idxconstructmarked\@idxsubtoks{#2}{#3}%
-  \@idxtokscollect
-}%
-%
-%
-% \@idxcollectname{FIRST}{LAST} puts `LAST, FIRST' into \temp. (Well,
-% we use \idxnameseparator instead of hardwiring `, '.) If FIRST is
-% empty, don't include the separator.
-% 
-\def\idxnameseparator{, }% as in `Tachikawa, Elizabeth'
-%
-\def\@idxcollectname#1#2{%
-  \def\temp{#1}%
-  \ifx\temp\empty
-    \toks@ = {}%
-  \else
-    \toks@ = {\idxnameseparator #1}%
-  \fi
-  \toks2 = {#2}%
-  %
-  \edef\temp{\the\toks2 \the\toks@}%
-}%
-%
-%
-% \@idxname{FIRST}{LAST} also produces `FIRST LAST' in the output and an
-% index entry for `LAST, FIRST'.
-%
-\def\@idxname#1#2{%
-  #1 #2% Separate the names by a space in the output.
-  \@idxcollectname{#1}{#2}%
-  \expandafter\@idxcollect\expandafter{\temp}{}%
-}%
-%
-% \@sidxname{FIRST}{LAST}[SUBTERM] is to \@sidx as \@idxname is to
-% \@idx.
-% 
-\def\@sidxname#1#2{%
-  \@idxcollectname{#1}{#2}%
-  \expandafter\@sidx\expandafter{\temp}%
-}%
-%
-%
-% Now we come to actually producing the index, i.e., implementing the
-% formatting commands that MakeIndex outputs.
-%
-% \readindexfile is responsible for formatting and printing the index.
-% It reads \indexfilebasename.ind.  We implement the same commands that
-% LaTeX does.  I suppose we could allow for different indices having
-% different basenames, but I can't imagine when that would be useful.
-% 
-\let\indexfonts = \relax
-%
-\def\readindexfile#1{%
-  \edef\@idxprefix{#1}%
-  %
-  % Does the output file exist?
-  \testfileexistence[\indexfilebasename]{\@idxprefix nd}%
-  \iffileexists \begingroup
-    % If no \begin or \end, define them. The argument will be `{theindex}'.
-    \ifx\begin\undefined
-      \def\begin##1{\@beginindex}%
-      \let\end = \@gobble
-    \fi
-    %
-    % Read the file:
-    \input \indexfilebasename.\@idxprefix nd
-    % 
-    % \doublecolumns isn't affected by groups.
-    \singlecolumn
-  \endgroup
-  \else
-    \message{No index file \indexfilebasename.\@idxprefix nd.}%
-  \fi
-}%
-%
-% Here's the default for `\begin{theindex}', if \begin isn't defined.
-\def\@beginindex{%
-  % Define the commands MakeIndex outputs.
-  \let\item = \@indexitem
-  \let\subitem = \@indexsubitem
-  \let\subsubitem = \@indexsubsubitem
-  %
-  % Set up the default formatting:
-  \indexfonts
-  \doublecolumns
-  \parindent = 0pt
-  %
-  % Let the user override the defaults.
-  \hookrun{beginindex}%
-}%
-%
-% MakeIndex puts \indexspace between groups in the ind file.
-\let\indexspace = \bigbreak
-%
-% You can make \afterindexterm appear after the term and before the
-% first page with the following in the ist file:
-% delim_0 "\\afterindexterm "
-% delim_1 "\\afterindexterm "
-% delim_2 "\\afterindexterm "
-\let\afterindexterm = \quad
-%
-%
-% Top-level index entries start with \item.
-\newskip\aboveindexitemskipamount  \aboveindexitemskipamount = 0pt plus2pt
-\def\aboveindexitemskip{\vskip\aboveindexitemskipamount}%
-%
-\def\@indexitem{\begingroup
-  \@indexitemsetup
-  \leftskip = 0pt
-  \aboveindexitemskip
-  \penalty-100 % Encourage page breaks before items.
-  % 
-  % But forbid page breaks after items, in case a subitem follows.
-  \def\par{\endgraf\endgroup\nobreak}%
-}%
-%
-% Secondary index entries.
-\def\@indexsubitem{%
-  \@indexitemsetup
-  \leftskip = 1em
-}%
-%
-% And tertiary entries.
-\def\@indexsubsubitem{%
-  \@indexitemsetup
-  \leftskip = 2em
-}%
-%
-% Common setup for the formatting.
-\def\@indexitemsetup{%
-  \par
-  \hangindent = 1em
-  \raggedright
-  \hyphenpenalty = 10000
-  \hookrun{indexitem}%
-}%
-%
-%
-% \indexsee{TERM}{PAGENO} ignores PAGENO, and says `see TERM'.
-\def\seevariant{\it}%
-\def\indexseeword{see}%
-\def\indexsee#1#2{{\seevariant \indexseeword\/ }#1}%
-%
-% \indexseealso{TERM}{PAGENO} is similar.
-\def\indexseealsowords{see also}%
-\def\indexseealso#1#2{{\seevariant \indexseealsowords\/ }#1}%
-%
-%
-% We provide one index by default; commands are \idx, \sidx, etc.
-\defineindex{i}%
-%
-%
-% 
-%  Justification of multiple input lines.
-%
-% You use these by saying 
-% {\flushright 
-% <flush right text>
-% }
-% 
-% and similarly for \flushleft and \center.  The command must be
-% embedded in a group.  The lines are set in paragraphs as usual, i.e.,
-% blank lines start a new paragraph (by virtue of the
-% \blanklineskipamount vertical glue being inserted).
-% 
-% \environment ... \endenvironment isn't appropriate in this case, since
-% these ``environments'' can't be nested.
-% 
-\begingroup
-  \catcode `\^^M = \active %
-  \gdef\flushleft{%
-    \def\@endjustifycmd{\@endflushleft}%
-    \def\@eoljustifyaction{\null\hfil\break}%
-    \let\@firstlinejustifyaction = \relax
-    \@startjustify %
-  }%
-  \gdef\flushright{%
-    \def\@endjustifycmd{\@endflushright}%
-    \def\@eoljustifyaction{\break\null\hfil}%
-    \def\@firstlinejustifyaction{\hfil\null}%
-    \@startjustify %
-  }%
-  \gdef\center{%
-    \def\@endjustifycmd{\@endcenter}%
-    \def\@eoljustifyaction{\hfil\break\null\hfil}%
-    \def\@firstlinejustifyaction{\hfil\null}%
-    \@startjustify %
-  }%
-  %
-  % We do this before starting any of the justification commands.
-  \gdef\@startjustify{%
-    \parskip = 0pt
-    \catcode`\^^M = \active %
-    \def^^M{\futurelet\next\@finjustifyreturn}%
-    %
-    % \@eateol is called at the beginning of each justified paragraph.
-    \def\@eateol##1^^M{%
-      \def\temp{##1}%
-      \@firstlinejustifyaction %
-      \ifx\temp\empty\else \temp^^M\fi %
-    }%
-    \expandafter\aftergroup\@endjustifycmd %
-    \checkenv \environmenttrue %
-    \par\noindent %
-    \@eateol %
-  }%
-  %
-  % If the next thing is a ^^M, insert \blanklineskipamount glue.  Then
-  % do \@eoljustifyaction (which each justification command defines).
-  \gdef\@finjustifyreturn{%
-    \@eoljustifyaction %
-    \ifx\next^^M%
-      % Insert extra glue when the \@end... command does the \par.
-      \def\par{\endgraf\vskip\blanklineskipamount \global\let\par = \endgraf}%
-      \@endjustifycmd %
-      % Get back into horizontal mode for the next line.
-      \noindent %
-      \@firstlinejustifyaction %
-    \fi %
-  }%
-\endgroup
-% 
-\def\@endflushleft{\unpenalty{\parfillskip = 0pt plus1fil\par}\ignorespaces}%
-\def\@endflushright{% Remove the \hfil\null\break we just put on.
-   \unskip \setbox0=\lastbox \unpenalty
-   % We have fil glue at the left of the line; \parfillskip shouldn't
-   % affect that.
-   {\parfillskip = 0pt \par}\ignorespaces
-}%
-\def\@endcenter{% Remove the \hfil\null\break we just put on.
-   \unskip \setbox0=\lastbox \unpenalty
-   % We have fil glue at the left of the line; \parfillskip must balance it.
-   {\parfillskip = 0pt plus1fil \par}\ignorespaces
-}%
-% 
-%
-% 
-%  Automatically-columnated tables.
-% 
-% \makecolumns N/K: organizes the entries on the following N lines into
-% K columns.  If N is too small, some text beyond the end of the table
-% will be incorporated into the table, probably producing an error
-% message.  If N is too large, some of the entries will appear after the
-% table, probably looking very out of place.
-% 
-% You can adjust the position of the table on the page by changing
-% \parindent (space to the left of the block) and \hsize (distance from
-% the left margin to the right of the block).  (No doubt inside a
-% group.)  And you can allow a page break above the valign by changing
-% \abovecolumnspenalty.
-% 
-\newcount\abovecolumnspenalty   \abovecolumnspenalty = 10000
-\newcount\@linestogo         % Lines remaining to process.
-\newcount\@linestogoincolumn % Lines remaining in column.
-\newcount\@columndepth       % Number of lines in a column.
-\newdimen\@columnwidth       % Width of each column.
-\newtoks\crtok  \crtok = {\cr}%
-\newcount\currentcolumn
-%
-% The space matches an end-of-line that will probably be there.
-% 
-\def\makecolumns#1/#2: {\par \begingroup
-   % Set \@columndepth to the number of items we will put in a column:
-   % ceiling(N/K), i.e.  (N - 1) / K + 1.
-   \@columndepth = #1
-   \advance\@columndepth by -1
-   \divide \@columndepth by #2
-   \advance\@columndepth by 1
-   \@linestogoincolumn = \@columndepth
-   \@linestogo = #1
-   %
-   % We start in the first column.
-   \currentcolumn = 1
-   %
-   \def\@endcolumnactions{%
-      \ifnum \@linestogo<2 
-         \the\crtok \egroup \endgroup \par % End \valign and \makecolumns.
-      \else
-         % We've done one more line out of the total.
-         \global\advance\@linestogo by -1
-         % 
-         % How many left in the column?
-         % 
-         \ifnum\@linestogoincolumn<2
-            % End this column, that was the last line.
-            \global\advance\currentcolumn by 1
-            \global\@linestogoincolumn = \@columndepth
-            \the\crtok
-         \else
-            % Still got more lines to go.
-            &\global\advance\@linestogoincolumn by -1
-         \fi
-      \fi
-   }%
-   %
-   % Set up to read the table.
-   % 
-   \makeactive\^^M
-   \letreturn \@endcolumnactions
-   % 
-   % Figure out how wide our columns are going to be; each column has
-   % exactly the same template, so we can use the feature described on
-   % p.241 of the TeXbook for repeating preambles.
-   % 
-   \@columnwidth = \hsize
-     \advance\@columnwidth by -\parindent
-     \divide\@columnwidth by #2
-   \penalty\abovecolumnspenalty
-   \noindent % It's not a paragraph (usually).
-   \valign\bgroup
-     &\hbox to \@columnwidth{\strut \hsize = \@columnwidth ##\hfil}\cr
-     %
-     % The next end-of-line starts everything going.
-}%
-%
-% 
-% 
-% \numberedfootnote is like plain TeX's \footnote, but automatically
-% numbered.  When you want to reset the footnote number, say
-% \footnotenumber = 0.
-% 
-% We also provide for more general formatting than \footnote:
-%   \footnotemarkseparation is the space between the reference mark and
-%     the footnote text;
-%  \interfootnoteskip is the space between footnotes;
-%  \everyfootnote is expanded just before we typeset the footnote.
-% 
-% The dimensions of the footnote rule are controlled by
-% \footnoterulewidth and \footnoteruleheight (the depth is always zero);
-% the space after the rule is \belowfootnoterulespace.
-% 
-\newcount\footnotenumber
-\newcount\hlfootlabelnumber
-\newdimen\footnotemarkseparation \footnotemarkseparation = .5em
-\newskip\interfootnoteskip \interfootnoteskip = 0pt
-\newtoks\everyfootnote
-\newdimen\footnoterulewidth \footnoterulewidth = 2in
-\newdimen\footnoteruleheight \footnoteruleheight = 0.4pt
-\newdimen\belowfootnoterulespace \belowfootnoterulespace = 2.6pt
-%
-\let\@plainfootnote = \footnote
-\let\@plainvfootnote = \vfootnote
-% Hyperlink labels for forward and back references.
-\def\hlfootlabel{FOOT\the\hlfootlabelnumber}%
-\def\hlfootbacklabel{FOOTB\the\hlfootlabelnumber}%
-%
-\def\@eplainfootnote#1{\let\@sf\empty % parameter #2 (the text) is read later
-  \ifhmode\edef\@sf{\spacefactor\the\spacefactor}\/\fi
-  \global\advance\hlfootlabelnumber by 1
-  \hlstart@impl{foot}{\hlfootlabel}%
-  \hldest@impl{footback}{\hlfootbacklabel}%
-  #1%
-  \hlend@impl{foot}%
-  \@sf\vfootnote{#1}%
-}%
-%
-\let\footnote\@eplainfootnote
-%
-\def\vfootnote#1{\insert\footins\bgroup
-  \interlinepenalty\interfootnotelinepenalty
-  \splittopskip\ht\strutbox % top baseline for broken footnotes
-  \advance\splittopskip by \interfootnoteskip
-  \splitmaxdepth\dp\strutbox
-  \floatingpenalty\@MM
-  \leftskip\z@skip \rightskip\z@skip \spaceskip\z@skip \xspaceskip\z@skip
-  \everypar = {}%
-  \parskip = 0pt % because of the vskip
-  % Even if typesetting in multicolumns, do footnotes in normal page width.
-  % (We don't have any provision in the output routine for having
-  % footnotes per column, anyway.)
-  \ifnum\@numcolumns > 1 \hsize = \@normalhsize \fi
-  \the\everyfootnote
-  \vskip\interfootnoteskip
-  \indent\llap{%
-    \hlstart@impl{footback}{\hlfootbacklabel}%
-    \hldest@impl{foot}{\hlfootlabel}%
-    #1%
-    \hlend@impl{footback}%
-    \kern\footnotemarkseparation
-  }%
-  \footstrut\futurelet\next\fo@t
-}%
-%
-\def\footnoterule{\dimen@ = \footnoteruleheight
-  \advance\dimen@ by \belowfootnoterulespace
-  \kern-\dimen@
-  \hrule width\footnoterulewidth height\footnoteruleheight depth0pt
-  \kern\belowfootnoterulespace
-  \vskip-\interfootnoteskip
-}%
-%
-\def\numberedfootnote{%
-  \global\advance\footnotenumber by 1
-  \@eplainfootnote{$^{\number\footnotenumber}$}%
-}%
-%
-%
-% 
-%  Margins.
-% 
-% TeX's primitives determine the type area.  But some users prefer to
-% think in terms of margins.  These definitions allow one to say, for
-% example, `\topmargin = 2in', instead of `\voffset=1in\advance\vsize by
-% -1in'.  Constructions like `\advance\topmargin by 1in' give an error
-% message, though, since \topmargin is not a parameter.  Instead, the
-% macro \advancetopmargin has to be used.
-% 
-\newdimen\paperheight 
-\ifnum\mag=1000
-  \paperheight = 11in % No magnification (yet).
-\else
-  \paperheight = 11truein % We already have a magnification. 
-\fi
-%
-\def\topmargin{\afterassignment\@finishtopmargin \dimen@}%
-\def\@finishtopmargin{%
-  \dimen2 = \voffset		% Remember the old \voffset.
-  \voffset = \dimen@ \advance\voffset by -1truein
-  \advance\dimen2 by -\voffset	% Compute the change in \voffset.
-  \advance\vsize by \dimen2	% Change type area accordingly.
-}%
-\def\advancetopmargin{%
-  \dimen@ = 0pt \afterassignment\@finishadvancetopmargin \advance\dimen@
-}%
-\def\@finishadvancetopmargin{%
-  \advance\voffset by \dimen@
-  \advance\vsize by -\dimen@
-}%
-%
-%
-\def\bottommargin{\afterassignment\@finishbottommargin \dimen@}%
-\def\@finishbottommargin{%
-  \@computebottommargin		% Result in \dimen2.
-  \advance\dimen2 by -\dimen@	% Compute the change in the bottom margin.
-  \advance\vsize by \dimen2	% Change the type area.
-}%
-\def\advancebottommargin{%
-  \dimen@ = 0pt \afterassignment\@finishadvancebottommargin \advance\dimen@
-}%
-\def\@finishadvancebottommargin{%
-  \advance\vsize by -\dimen@
-}%
-%
-% Find the current bottom margin, putting the result in \dimen2.
-% 
-\def\@computebottommargin{%
-  \dimen2 = \paperheight	% The total paper size.
-  \advance\dimen2 by -\vsize	% Less the text size.
-  \advance\dimen2 by -\voffset	% Less the offset at the top.
-  \advance\dimen2 by -1truein	% Less the default offset.
-}%
-% 
-% 
-\newdimen\paperwidth
-\ifnum\mag=1000
-  \paperwidth = 8.5in % No magnification (yet).
-\else
-  \paperwidth = 8.5truein % We already have a magnification. 
-\fi
-%
-\def\leftmargin{\afterassignment\@finishleftmargin \dimen@}%
-\def\@finishleftmargin{%
-  \dimen2 = \hoffset		% Remember the old \hoffset.
-  \hoffset = \dimen@ \advance\hoffset by -1truein
-  \advance\dimen2 by -\hoffset	% Compute the change in \hoffset.
-  \advance\hsize by \dimen2	% Change type area accordingly.
-}%
-\def\advanceleftmargin{%
-  \dimen@ = 0pt \afterassignment\@finishadvanceleftmargin \advance\dimen@
-}%
-\def\@finishadvanceleftmargin{%
-  \advance\hoffset by \dimen@
-  \advance\hsize by -\dimen@
-}%
-%
-%
-\def\rightmargin{\afterassignment\@finishrightmargin \dimen@}%
-\def\@finishrightmargin{%
-  \@computerightmargin		% Result in \dimen2.
-  \advance\dimen2 by -\dimen@	% Compute the change in the right margin.
-  \advance\hsize by \dimen2	% Change the type area.
-}%
-\def\advancerightmargin{%
-  \dimen@ = 0pt \afterassignment\@finishadvancerightmargin \advance\dimen@
-}%
-\def\@finishadvancerightmargin{%
-  \advance\hsize by -\dimen@
-}%
-%
-% Find the current right margin, putting the result in \dimen2.
-% 
-\def\@computerightmargin{%
-  \dimen2 = \paperwidth		% The total paper size.
-  \advance\dimen2 by -\hsize	% Less the text size.
-  \advance\dimen2 by -\hoffset	% Less the offset at the left.
-  \advance\dimen2 by -1truein	% Less the default offset.
-}%
-% 
-% There is a potential problem when using the margin macros at a true
-% dimension and then calling \magnification. So we redefine
-% \magnification to address this. 
-% 
-\let\@plainm@g = \m@g
-\def\m@g{\@plainm@g \paperwidth = 8.5 true in \paperheight = 11 true in}%
-%
-% 
-% 
-%  Double column output.
-%
-% \doublecolumns begins double column output.  It can be called
-% in the midst of a page.  \singlecolumn restores single column 
-% output.  (It would be wrong to require \enddoublecolumns, because 
-% often one wants double column mode to continue to the end of 
-% the document.)
-%
-% The basic approach is that of Appendix E of the TeXbook, p.417.
-% David Guichard made significant improvements to my original implementation.
-%
-% The glue here (the default is intended to be one linespace) is inserted
-% before double columns start, and after they end.
-%
-\newskip\abovecolumnskip \abovecolumnskip = \bigskipamount
-\newskip\belowcolumnskip \belowcolumnskip = \bigskipamount
-%
-% Space between the columns. It can be changed as desired.
-\newdimen\gutter \gutter = 2pc
-%
-% These registers are needed for dealing with switching back and forth.
-\newbox\@partialpage
-\newdimen\@normalhsize
-\newdimen\@normalvsize  % The original (before multi-columns) \vsize.
-\newtoks\previousoutput
-%
-% Some synonymous ways to refer to multiple column modes.
-\def\quadcolumns{\@columns4}%
-\def\triplecolumns{\@columns3}%
-\def\doublecolumns{\@columns2}%
-\def\begincolumns#1{\ifcase#1\relax \or \singlecolumn \or \@columns2 \or
-                            \@columns3 \or \@columns4 \else \relax \fi}%
-\def\endcolumns{\singlecolumn}%
-\let\@ndcolumns = \relax
-%
-% Set this by default so \vfootnote can unconditionally inspect it.
-\chardef\@numcolumns = 1
-%
-\mathchardef\@ejectpartialpenalty = 10141
-%
-%
-% \@columns:  Start typesetting with #1 columns.
-%
-% Before we actually start, we have to make sure that there are at least
-\chardef\@col@minlines = 3
-% free lines.
-% (It could be 2, or even 1, but it might give ugly results; at least one
-% line is absolutely necessary, or the output routine might get confused.)
-% We have to be careful, so that eg.
-%	\hbox{TITLE}
-%	\nobreak
-%	\doublecolumns
-% won't break between the title and the start of the columned output.
-%
-% To achieve this, we add vskip of fixed size equal to
-%	@col@minlines * baselineskip
-% and then eject the page.
-% The output routine then catches the pages ejected:
-%  1) if it's a normal page, it is processed by previous output routine;
-%  2) if it's the last one, it is saved and the added skip is removed.
-%
-% When the box is processed according to 1), an underfull vbox can appear,
-% but it's not our problem, the manuscript (or it's macros) has to be fixed.
-%
-% Another note: all assignments are global; it is not possible to call
-% \doublecolumns in a group.
-%
-\def\@columns#1{%
-  \@ndcolumns
-  %
-  \global\let\@ndcolumns = \@endcolumns
-  \global\chardef\@numcolumns = #1
-  \global\previousoutput = \expandafter{\the\output}%
-  %
-  % Grab the page so far (i.e., the material BEFORE \@columns was called)
-  % and save it in \@partialpage.
-  \global\output = {%
-    \ifnum\outputpenalty = -\@ejectpartialpenalty
-      \dimen@ = \vsize
-      \advance\dimen@ by \@col@minlines\baselineskip
-      \global\setbox\@partialpage =
-        \vbox  \ifdim \pagetotal > \vsize  to \dimen@  \fi  {%
-	  \unvbox255 \unskip
-	}%
-    \else
-      \the\previousoutput
-    \fi
-  }%
-  %
-  \vskip \abovecolumnskip
-  \vskip \@col@minlines\baselineskip
-  % now execute the output routine:
-  \penalty -\@ejectpartialpenalty
-  %
-  % Reset \output to prepare for the first real page break.
-  \global\output = {\@columnoutput}%
-  %
-  \global\@normalhsize = \hsize
-  \global\@normalvsize = \vsize
-  %
-  % Figure out how wide the columns should be -- for n columns,
-  % decrement by n - 1 gutters.
-  \count@ = \@numcolumns
-  \advance\count@ by -1
-  \global\advance\hsize by -\count@\gutter
-  \global\divide\hsize by \@numcolumns
-  %
-  % Compute \vsize based on what's already on the page
-  % and the number of columns. Also change the mag factor for insertions.
-  %
-  \advance\vsize by -\ht\@partialpage
-  %
-  \advance\vsize by -\ht\footins
-  \ifvoid\footins\else \advance\vsize by -\skip\footins \fi
-  \multiply\count\footins by \@numcolumns
-  %
-  \advance\vsize by -\ht\topins
-  \ifvoid\topins\else \advance\vsize by -\skip\topins \fi
-  \multiply\count\topins by \@numcolumns
-  %
-  \global\vsize = \@numcolumns\vsize
-}%
-%
-% When this is invoked box 255 contains just the right amount of
-% material, whether triggered by an output routine or a change in the
-% number of columns. Because columns have to contain an integral number
-% of lines of type, we take a bit of care with balancing the heights of
-% the columns to prevent either losing material or having a very short
-% last column.
-%
-% When a page ends due to \bye or \eject, box 255 will contain lots of
-% white space, so the columns will not look balanced. To fix this use
-% \singlecolumn before ending the page.
-%
-% [gutterbox material added by AHL on 5 November 1997.]
-% \gutterbox is a hook to enable the placement of arbitrary vertical
-% material in the gutter between columns. For example, to put a
-% vertical line between the columns you could say 
-%
-%   \def\gutterbox{\vbox to \dimen0{\vfil\hbox{\vrule height\dimen0}\vfil}}%
-%
-% The dimension counter \dimen0 contains the height of the column. 
-%
-% By default, we define \gutterbox to be "empty": 
-\def\gutterbox{\vbox to \dimen0{\vfil\hbox{\hfil}\vfil}}%
-%
-% [This next paragraph added by AHL on 22 Sep 1996.]
-% There is a special case we have to worry about, namely when we
-% switch from multiple columns to single columns. In this case, we may
-% have a bit of text left over that doesn't fit evenly into the
-% multiple columns. In that case, we will have un-even columns. Not a
-% pretty solution, but I don't have a better one at the moment. The
-% conditional \if@forceextraline tests whether we are in this case.
-%
-\newif\if@forceextraline\@forceextralinefalse
-\def\@columnsplit{%
-  \splittopskip = \topskip
-  \splitmaxdepth = \baselineskip
-  %
-  % \dimen@ will be the height that the double-column material on this
-  % page should have, i.e., the height of the page (\singlecolumvsize)
-  % minus single-column material, which includes insertions.  (If you
-  % want your insertions to respect the columns, you will have to
-  % change the output routine.)  If you add more insertions, they
-  % should be taken into account both here and in \singlecolumn.
-  %
-  % Unfortunately, we lose on flexible glue because we must
-  % \vsplit to a <dimen>.
-  \dimen@ = \ht255
-    \divide\dimen@ by \@numcolumns
-  %
-  % If we are in an end-column mode and we need extra vertical space
-  % in the last column, advance \dimen@. 
-  \if@forceextraline
-    \advance\dimen@ by \baselineskip
-  \fi
-  %
-  % Split the long scroll into columns.
-  \begingroup
-    % We do not want to see underfull \vbox messages unless the final
-    % page is underfull.
-    \vbadness = 10000
-    %
-    % The first (leftmost) column.
-    \global\setbox1 = \vsplit255 to \dimen@  \global\wd1 = \hsize
-    %
-    % The second column.
-    \global\setbox3 = \vsplit255 to \dimen@  \global\wd3 = \hsize
-    %
-    \ifnum\@numcolumns > 2
-      % The third column, if requested.
-      \global\setbox5 = \vsplit255 to \dimen@ \global\wd5 = \hsize
-    \fi
-    \ifnum\@numcolumns > 3
-      % The fourth column, likewise if requested.
-      \global\setbox7 = \vsplit255 to \dimen@ \global\wd7 = \hsize
-    \fi
-  \endgroup
-  \if@forceextraline                         % If this is the first time
-  \else                                      % through, save the single
-    \setbox\@forcelinebox=\copy\@partialpage % column material. 
-  \fi
-  % 
-  % Set up \box255 with the real output page, as the previous output
-  % routine expects.
-  \setbox0 = \box255
-  \global\setbox255 = \vbox{%
-    \unvbox\@partialpage
-    \ifcase\@numcolumns \relax\or\relax
-      \or \hbox to \@normalhsize{\box1\hfil\gutterbox\hfil\box3}%
-      \or \hbox to \@normalhsize{\box1\hfil\gutterbox\hfil\box3%
-                                      \hfil\gutterbox\hfil\box5}%
-      \or \hbox to \@normalhsize{\box1\hfil\gutterbox\hfil\box3%
-                                      \hfil\gutterbox\hfil\box5%
-                                      \hfil\gutterbox\hfil\box7}%
-    \fi
-  }%
-  %
-  % Save what's left over in a private register before calling their
-  % output routine.
-  \setbox\@partialpage = \box0
-}%
-%
-% Our output routine splits the columns and then calls the previous one.
-% 
-\def\@columnoutput{%
-  \@columnsplit
-  \@recoverclubpenalty 
-  \hsize = \@normalhsize % Local to \output's group.
-  \vsize = \@normalvsize
-  \the\previousoutput
-  %
-  % Put back what didn't fit.
-  \unvbox\@partialpage
-  \penalty\outputpenalty
-  %
-  % The correct vsize is the original vsize times the
-  % number of columns.
-  \global\vsize = \@numcolumns\@normalvsize
-}%
-%
-% Go back to single-column typesetting.  Assume \doublecolumns has
-% been called.
-% 
-\def\singlecolumn{%
-  \@ndcolumns
-  \chardef\@numcolumns = 1
-  \vskip\belowcolumnskip
-  \nointerlineskip
-}%
-%
-\newbox\@forcelinebox 
-\def\@endcolumns{%
-  \global\let\@ndcolumns = \relax
-  \par % Shouldn't start in horizontal mode.
-  %
-  \global\output = {\global\setbox1 = \box255}%
-  \pagegoal = \pagetotal
-  \break                     % Exercise the page builder, i.e., \output.
-  \setbox2 = \box1           % Save material in box2 in case of overflow.
-  \global\setbox255 = \copy2 % Retrieve what the fake \output set.
-  %
-  % \box255 now has the double-column material.  On the page where we
-  % switch back to one column, the double-column material might not
-  % fill up the page.  We want to split whatever is there.
-  \@columnsplit
-  %
-  % Check that \@columnsplit did not leave any lines in
-  % \@partialpage. If it did, do it again, but this time with longer
-  % columns. 
-  \ifvoid\@partialpage
-  \else % There is some left-over. 
-    \setbox0=\box\@partialpage % Merely to void \@partialpage
-    \global\setbox255 = \box2  % Retrieve what the fake \output set.
-    \@forceextralinetrue       % Add \forcelinebox to \box255 to save single
-    \@columnsplit              % column material. 
-    \global\setbox255 = \vbox{\box\@forcelinebox\box255}%
-  \fi
-
-  \global\vsize = \@normalvsize
-  \global\hsize = \@normalhsize
-  \global\output = \expandafter{\the\previousoutput}%
-  %
-  \ifvoid\topins\else\topinsert\unvbox\topins\endinsert\fi
-  \unvbox255
-}%
-% [\columnfill]
-% We don't have any way to force a column eject, since the \output
-% routine is only prepared to split up a full page of material. Instead,
-% we provide the following as a guess at enough space to fill up the
-% current column.
-%
-% [April 30, 1998] This definition is from
-% Helmut Jarausch <jarausch@IGPM.Rwth-Aachen.DE> with some
-% modifications by A. Lewenberg <ahl@uakron.edu>. 
-%
-% Here is the main difficulty: when \vsplitting the long page into the
-% component columns, \vsplit prepends to the top of each column glue
-% in the amount \topskip - (height of top box). But this happens
-% in the output routine _after_ the \columnfill does its
-% calculations. The result of this is that if we are not careful
-% \columnfill will insert too much space attempting to ``eject'' the
-% current column. There is no simple way around this, so what I have
-% done is have is make \columnfill insert less space than needed, and
-% then not allow any \club lines by setting \clubpenalty to its
-% maximum value. Not a pretty solution, but until something better
-% comes along, it will have to do. 
-%
-\def\@saveclubpenalty{% save the current value of \clubpenalty
-  \edef\@recoverclubpenalty{%
-     \global\clubpenalty=\the\clubpenalty\relax%
-     \global\let\noexpand\@recoverclubpenalty\relax
-  }% the \noexpand handles infinite self-reference
-}%
-\let\@recoverclubpenalty\relax
-\newdimen\temp@dimen
-\def\columnfill{%
-  \par
-  \dimen@=\pagetotal   % The height of the text set so far. 
-  \temp@dimen = \vsize % = \@numcolumns * columnheight
-  \divide\temp@dimen by \@numcolumns % find out column height
-  \loop
-    \ifdim \dimen@ > \temp@dimen
-      \advance \dimen@ by -\temp@dimen
-      \advance \dimen@ by \topskip % fudge factor
-  \repeat
-  \advance \temp@dimen by -\dimen@
-  \advance \temp@dimen by -\prevdepth
-  \@saveclubpenalty 
-  \clubpenalty=10000\relax
-  \hrule height\temp@dimen width0pt depth0pt\relax
-  \nointerlineskip
-  \par
-  \nointerlineskip
-  \penalty0\vfil % To allow a page break here.
-  \relax
-}%
-%
-%
-%
-%  Hypertext links support.
-%
-% Hyperlink destinations (driver-independent code).
-%
-% \hldest{TYPE}{OPTIONS}{LABEL} defines a hyperlink destination
-% LABEL.  OPTIONS is a comma-separated list of option assignments of
-% the form `opt=value'; permitted values for TYPE and OPTIONS depend
-% on selected hyperlink driver.
-%
-% \hldest will be \let to \@hldest by \enablehyperlinks.  TYPE,
-% OPTIONS and LABEL will be read by \hl@getparam.
-\def\@hldest{%
-  \def\hl@prefix{hldest}%
-  \let\after@hl@getparam\hldest@aftergetparam
-  % Start the group which will isolate option settings.  It will be
-  % ended in \hldest@aftergetparam
-  \begingroup
-    \hl@getparam
-}%
-% This actually produces hyperlink destination.  It will be called at
-% the end of \hl@getparam, after the parameters are parsed.
-\def\hldest@aftergetparam{%
-  \ifvmode
-    % In vertical mode we don't raise the destination, so it can go
-    % directly into the vertical list.
-    \hldest@driver
-  \else
-    % In horizontal mode, the destination is raised \hldest@opt@raise
-    % above the baseline and placed inside a zero-width/height/depth
-    % box; the box is surrounded by \allowhyphens in case it is
-    % placed next to a word, to allow hyphenation of that word.
-    \allowhyphens
-    \smash{\ifx\hldest@opt@raise\empty \else \raise\hldest@opt@raise\fi
-             \hbox{\hldest@driver}}%
-    \allowhyphens
-  \fi
-  % End the group which was isolating option settings (it was started
-  % in \@hldest).
-  \endgroup
-}%
-%
-% Hyperlinks (driver-independent code).
-%
-% \hlstart{TYPE}{OPTIONS}{LABEL} starts a hyperlink to destination
-% LABEL.  OPTIONS is a comma-separated list of option assignments of
-% the form `opt=value'; permitted values of TYPE and OPTIONS depend on
-% selected hyperlink driver.  End the link with \hlend.
-%
-% \hlstart will be \let to \@hlstart by \enablehyperlinks.  TYPE,
-% OPTIONS and LABEL will be read by \hl@getparam.
-\def\@hlstart{%
-  \leavevmode
-  \def\hl@prefix{hl}%
-  \let\after@hl@getparam\hlstart@aftergetparam
-  % Start the group which will isolate option settings and color
-  % changes.  It will be ended in \@hlend
-  \begingroup
-    \hl@getparam
-}%
-%
-\def\hlstart@aftergetparam{%
-  % Set the color for the link.
-  \ifx\color\undefined \else
-    \ifx\hl@opt@color\empty \else
-      \ifx\hl@opt@colormodel\empty
-        \edef\temp{\noexpand\color{\hl@opt@color}}%
-      \else
-        \edef\temp{\noexpand\color[\hl@opt@colormodel]{\hl@opt@color}}%
-      \fi
-      \temp
-    \fi
-  \fi
-  % Call the driver.
-  \hl@driver
-}%
-% \hlend will be \let to \@hlend by \enablehyperlinks.  \@hlend will
-% be defined by a driver.
-%
-% Macros which are used commonly by \hldest and \hlstart to parse and
-% save parameters.  \hl@prefix must be set to `hldest' by \hldest and
-% to `hl' by \hlstart.
-%
-% \hl@getparam{TYPE}{OPTIONS}{LABEL} reads, parses and saves the
-% parameters for \hldest or \hlstart into \@hltype, \hl[dest]@opt@...
-% and \@hllabel.  After doing that it calls \after@hl@getparam which
-% should be defined by \@hldest and \@hlstart to produce destination /
-% link using the saved parameters.
-\def\hl@getparam#1#2#3{%
-  % Save TYPE in \@hltype (use default if empty).
-  \edef\@hltype{#1}%
-  \ifx\@hltype\empty
-    \expandafter\let\expandafter\@hltype
-      \csname \hl@prefix @type\endcsname
-  \fi
-  % For each supported destination / link type TYPE, a driver should
-  % define \hl[dest]@typeh@TYPE handler.
-  \expandafter\ifx\csname \hl@prefix @typeh@\@hltype\endcsname \relax
-    \errmessage{Invalid type `\@hltype'}%
-  \fi
-  % \for will expand #2 once so user can pass a shortcut macro.  We
-  % also ignore empty \hl@arg, so that the following
-  %     \hldest{TYPE}{\myopt,height=200pt}{LABEL}
-  % would be legal even when \myopt happens to be empty.
-  \for\hl@arg:=#2\do{%
-    \ifx\hl@arg\empty \else
-      \expandafter\hl@set@opt\hl@arg=,%
-    \fi
-  }%
-  % Save LABEL in \@hllabel.
-  \edef\@hllabel{#3}%
-  % Execute the commands specific to destination / link
-  \after@hl@getparam
-  % Ignore spaces after \hlstart and \hldest.
-  \ignorespaces
-}%
-% Parse and set a (default, not a group) option.
-\def\hl@set@opt#1=#2,{%
-  % For each supported option OPTION, a driver should define
-  % \hl[dest]@opt@OPTION.
-  \expandafter\ifx\csname \hl@prefix @opt@#1\endcsname \relax
-    \errmessage{Invalid option `#1'}%
-  \fi
-  % Save the value of the option.
-  \if ,#2, % if #2 is empty, complain.
-    \errmessage{Missing value for option `#1'}%
-  \else
-    % Remove a trailing =.
-    \def\temp##1={##1}%
-    \expandafter\edef\csname \hl@prefix @opt@#1\endcsname{\temp#2}%
-  \fi
-}%
-% \hl{dest,start,end}@impl{GROUP}{LABEL} will generate `implicit' destination /
-% hyperlink, if the user has not turned off this kind of implicit
-% destinations / hyperlinks.  This is used by Eplain's cross-reference
-% macros.
-\def\hldest@impl#1{%
-  \expandafter\ifcase\csname hldest@on@#1\endcsname
-    \relax\expandafter\gobble
-  \else
-    \toks@=\expandafter{\csname hldest@type@#1\endcsname}%
-    \toks@ii=\expandafter{\csname hldest@opts@#1\endcsname}%
-    \edef\temp{\noexpand\hldest{\the\toks@}{\the\toks@ii}}%
-    \expandafter\temp
-  \fi
-}%
-\def\hlstart@impl#1{%
-  \expandafter\ifcase\csname hl@on@#1\endcsname
-    % Still produce \leavevmode, to be consistent with \hloff.
-    \leavevmode\expandafter\gobble
-  \else
-    \toks@=\expandafter{\csname hl@type@#1\endcsname}%
-    \toks@ii=\expandafter{\csname hl@opts@#1\endcsname}%
-    \edef\temp{\noexpand\hlstart{\the\toks@}{\the\toks@ii}}%
-    \expandafter\temp
-  \fi
-}%
-\def\hlend@impl#1{%
-  \expandafter\ifcase\csname hl@on@#1\endcsname
-  \else
-    \hlend
-  \fi
-}%
-%
-% Setting options and types.
-%
-\def\hl@asterisk@word{*}%
-\def\hl@opts@word{opts}%
-\newif\if@params@override
-% We define hyperlink / destination groups.  A group is a macro or a
-% group of macros which implicitly generate hyperlink / destination.
-% The user can set parameters for each group individually, as well as
-% the default parameters, with the macros defined below.  Group
-% settings will override the default hyperlink / destination
-% parameters.
-\def\hldest@groups{definexref,xrdef,li,eq,bib,foot,footback,idx}%
-\def\hl@groups{ref,xref,eq,cite,foot,footback,idx,url}%
-% \hldesttype [GROUPS]{VALUE}
-% \hldestopts [GROUPS]{VALUE}
-% \hltype     [GROUPS]{VALUE}
-% \hlopts     [GROUPS]{VALUE}
-%
-% Set hyperlink or destination parameter (type / opts) to VALUE for
-% each group in GROUPS.  An empty `group' will set default value for
-% the parameter.  A star (*) `group' stands for all groups (exept the
-% empty `group').  If the macro is followed by an exclamation mark
-% (like \hlopts!...), the parameters will be overridden; otherwise,
-% they will be updated (this has effect only on group option list).
-\def\hldesttype{%
-  \def\hl@prefix{hldest}%
-  \def\hl@param{type}%
-  \let\hl@all@groups\hldest@groups
-  \futurelet\hl@excl\hl@param@read@excl
-}%
-\def\hldestopts{%
-  \def\hl@prefix{hldest}%
-  \def\hl@param{opts}%
-  \let\hl@all@groups\hldest@groups
-  \futurelet\hl@excl\hl@param@read@excl
-}%
-\def\hltype{%
-  \def\hl@prefix{hl}%
-  \def\hl@param{type}%
-  \let\hl@all@groups\hl@groups
-  \futurelet\hl@excl\hl@param@read@excl
-}%
-\def\hlopts{%
-  \def\hl@prefix{hl}%
-  \def\hl@param{opts}%
-  \let\hl@all@groups\hl@groups
-  \futurelet\hl@excl\hl@param@read@excl
-}%
-\def\hl@param@read@excl{%
-  \ifx!\hl@excl
-    \let\next\hl@param@read@opt@arg
-    \@params@overridetrue
-  \else
-    \def\next{\hl@param@read@opt@arg{!}}%
-    \@params@overridefalse
-  \fi
-  \next
-}%
-\def\hl@param@read@opt@arg#1{% #1 is the `!', ignore it.
-  \@getoptionalarg\hl@setparam
-}%
-% Set the parameter \hl@param to #1 for each group in \@optionalarg.
-\def\hl@setparam#1{%
-  \ifx\@optionalarg\empty
-    \hl@setparam@default{#1}% Set default.
-  \else
-    % If we find an asterisk in the list, we have no choice but to
-    % finish the list and then call \hl@setparam again, now with
-    % \hl@all@groups for the list of groups.
-    \let\hl@do@all@groups\gobble
-%
-    \for\hl@group:=\@optionalarg\do{%
-      \ifx\hl@group\hl@asterisk@word
-        \def\hl@do@all@groups{\let\@optionalarg\hl@all@groups \hl@setparam}%
-      \else
-        \hl@setparam@group{#1}%
-      \fi
-    }%
-%
-    \hl@do@all@groups{#1}%
-  \fi
-}%
-% Set a parameter (\hl@param) for one group (\hl@group) to the value
-% (#1).  The group may be empty, in which case we call
-% \hl@setparam@default
-\def\hl@setparam@group#1{%
-  \ifx\hl@group\empty
-    \hl@setparam@default{#1}%
-  \else
-    \expandafter\ifx\csname\hl@prefix @\hl@param @\hl@group\endcsname\relax
-      \errmessage{Hyperlink group parameter `\hl@prefix:\hl@param:\hl@group' is not defined}%
-    \fi
-    \ifx\hl@param\hl@opts@word
-      % For the `opts' parameter, we want to expand the first token of
-      % #1 once, in case the user passed a macro containing the option
-      % list.  We may need to either simply override the old option
-      % list, or to update it with the new option settings.
-      \if@params@override
-        \toks@=\expandafter{#1}%
-        \ece\edef{\hl@prefix @\hl@param @\hl@group}{\the\toks@}%
-      \else
-        \hl@update@opts@with@list{#1}% #1 will be used in the \for
-                                % loop, so it will be expanded once.
-      \fi
-    \else
-      % Do not use \edef here to define the parameter, so the user can
-      % define it to, e.g., \normalbaselineskip, and make the parameter
-      % adjustable to a situation.
-      \ece\def{\hl@prefix @\hl@param @\hl@group}{#1}%
-    \fi
-  \fi
-}%
-% Set default parameter values.  We have to treat `opts' (list of
-% options) specially, because for option defaults we don't store a
-% list of options (like we do for the group options) but set each
-% option individually.
-\def\hl@setparam@default#1{%
-  \ifx\hl@param\hl@opts@word
-    % `opts'.
-    \for\hl@opt:=#1\do{%
-      \ifx\hl@opt\empty \else
-        \expandafter\hl@set@opt\hl@opt=,%
-      \fi
-    }%
-  \else
-    % Everything except `opts'.
-    \expandafter\ifx\csname\hl@prefix @\hl@param\endcsname\relax
-      \message{Default parameter `\hl@prefix:\hl@param' is not defined}%
-    \fi
-    % Should not use \edef, so the user could define this to, e.g.,
-    % \normalbaselineskip, to make the parameter adjustable to a
-    % situation.
-    \ece\def{\hl@prefix @\hl@param}{#1}%
-  \fi
-}%
-% For each option in the list (#1), call \hl@update@with@opt to update
-% the group's option list (\csname\hl@prefix @opts@ \hl@group\endcsname)
-% with this new option.
-\def\hl@update@opts@with@list#1{%
-  % Start with the current list of the group.
-  \global\expandafter\let\expandafter\hl@update@new@list
-    \csname \hl@prefix @opts@\hl@group\endcsname
-  % We have to isolate the \for loop inside a (TeX) group, to avoid
-  % clashes with the loop in \hl@setparam
-  \begingroup
-    \for\hl@opt:=#1\do{%
-      \hl@update@opts@with@opt
-    }%
-  \endgroup
-  % Save the final list back in the option list for the group.
-  \ece\let{\hl@prefix @opts@\hl@group}\hl@update@new@list
-}%
-% Go through the option list (\hl@update@new@list) and construct the
-% new list (in \hl@update@new@list), replacing the old definition of
-% the option with the new one (\hl@opt).
-\def\hl@update@opts@with@opt{%
-  % Save the old list and the new option.
-  \global\let\hl@update@old@list\hl@update@new@list
-  \global\let\hl@update@new@list\empty
-  \global\let\hl@update@new@opt\hl@opt
-  % Get the key of the new option and save it.
-  \expandafter\hl@parse@opt@key\hl@opt=,%
-  \let\hl@update@new@key\hl@update@key
-  % We will set this to real comma after the first entry.
-  \global\let\hl@update@comma\empty
-  % We have to isolate the \for loop inside a (TeX) group, to avoid
-  % clashes with the loop in \hl@update@opts@with@list
-  \begingroup
-    \for\hl@opt:=\hl@update@old@list\do{%
-      \ifx\hl@opt\empty \else % Skip empty `options'.
-        % Get the key of this option.
-        \expandafter\hl@parse@opt@key\hl@opt=,%
-        % If the key matches, replace the option definition with the
-        % new definition, otherwise, repeat the old definition.
-        \toks@=\expandafter{\hl@update@new@list}%
-        \ifx\hl@update@key\hl@update@new@key
-          \ifx\hl@update@new@opt\empty \else % Skip multiple options.
-            \toks@ii=\expandafter{\hl@update@new@opt}%
-            \xdef\hl@update@new@list{\the\toks@\hl@update@comma\the\toks@ii}%
-            \global\let\hl@update@new@opt\empty
-            \global\def\hl@update@comma{,}%
-          \fi
-        \else
-          \toks@ii=\expandafter{\hl@opt}%
-          \xdef\hl@update@new@list{\the\toks@\hl@update@comma\the\toks@ii}%
-          \global\def\hl@update@comma{,}%
-        \fi
-      \fi
-    }%
-  \endgroup
-  % If nothing was replaced, add the new option to the end of the new list.
-  \ifx\hl@update@new@opt\empty \else
-    \toks@=\expandafter{\hl@update@new@list}%
-    \toks@ii=\expandafter{\hl@update@new@opt}%
-    \xdef\hl@update@new@list{\the\toks@\hl@update@comma\the\toks@ii}%
-  \fi
-}%
-% Parse the key of the option and save it in \hl@update@key
-\def\hl@parse@opt@key#1=#2,{\def\hl@update@key{#1}}%
-%
-% Default and group parameters (options and types).
-%
-% Option `raise' will determine how much to raise hyperlink
-% destinations above the baseline.  It will be supported by all
-% drivers, since it is handled outside the drivers, in
-% \hldest@aftergetparam.
-\def\hldest@opt@raise{\normalbaselineskip}%
-% Options `colormodel' and `color' will also be handled outside the
-% drivers, in \hlstart@aftergetparam.
-\def\hl@opt@colormodel{cmyk}%
-\def\hl@opt@color{0.28,1,1,0.35}%
-%
-% Parameters for destinations and links produced implicitly by
-% cross-reference macros.  Note that each driver will additionally
-% define \hldest@type and \hl@type parameters which will be used when
-% one of the below is empty, and default values for destination and
-% link options (which are driver-specific).
-%
-% Destination on/off flags (0=off, 1=on).
-\def\hldest@on@definexref{0}%
-\def\hldest@on@xrdef{0}%
-\def\hldest@on@li{0}%
-\def\hldest@on@eq{0}% \eqdef and friends
-\def\hldest@on@bib{0}% \biblabelprint (BibTeX)
-\def\hldest@on@foot{0}% \footnote / \numberedfootnote
-\def\hldest@on@footback{0}% back-ref for \footnote / \numberedfootnote
-\def\hldest@on@idx{0}% both `page' dests and `exact' dests
-% Types of destinations.
-\let\hldest@type@definexref\empty
-\let\hldest@type@xrdef\empty
-\let\hldest@type@li\empty
-\let\hldest@type@eq\empty % \eqdef and friends
-\let\hldest@type@bib\empty % \biblabelprint (BibTeX)
-\let\hldest@type@foot\empty % \footnote / \numberedfootnote
-\let\hldest@type@footback\empty % back-ref for \footnote / \numberedfootnote
-\let\hldest@type@idx\empty % both `page' dests and `exact' dests
-% Options for destinations.
-\let\hldest@opts@definexref\empty
-\let\hldest@opts@xrdef\empty
-\let\hldest@opts@li\empty
-\def\hldest@opts@eq{raise=1.7\normalbaselineskip}% \eqdef and friends
-\let\hldest@opts@bib\empty % \biblabelprint (BibTeX)
-\let\hldest@opts@foot\empty % \footnote / \numberedfootnote
-\let\hldest@opts@footback\empty % back-ref for \footnote / \numberedfootnote
-\let\hldest@opts@idx\empty % both `page' dests and `exact' dests
-%
-% Hyperlink on/off flags (0=off, 1=on).
-\def\hl@on@ref{0}% \refn and \xrefn, \ref, \refs
-\def\hl@on@xref{0}%
-\def\hl@on@eq{0}% \eqref and \eqrefn
-\def\hl@on@cite{0}% \cite (BibTeX)
-\def\hl@on@foot{0}% \footnote / \numberedfootnote
-\def\hl@on@footback{0}% back-reference for \footnote / \numberedfootnote
-\def\hl@on@idx{0}%
-\def\hl@on@url{0}% \url from url.sty
-% Types of links.
-\let\hl@type@ref\empty % \refn and \xrefn, \ref, \refs
-\let\hl@type@xref\empty
-\let\hl@type@eq\empty % \eqref and \eqrefn
-\let\hl@type@cite\empty % \cite (BibTeX)
-\let\hl@type@foot\empty % \footnote / \numberedfootnote
-\let\hl@type@footback\empty % back-reference for \footnote / \numberedfootnote
-\let\hl@type@idx\empty
-\let\hl@type@url\empty % \url from url.sty (this will be set to `url' by
-                       % drivers which support the `url' type)
-% Options for links.
-\let\hl@opts@ref\empty % \refn and \xrefn, \ref, \refs
-\let\hl@opts@xref\empty
-\let\hl@opts@eq\empty % \eqref and \eqrefn
-\let\hl@opts@cite\empty % \cite (BibTeX)
-\let\hl@opts@foot\empty % \footnote / \numberedfootnote
-\let\hl@opts@footback\empty % back-reference for \footnote / \numberedfootnote
-\let\hl@opts@idx\empty
-\let\hl@opts@url\empty % \url from url.sty
-%
-% \@hlon[GROUPS]
-% \@hloff[GROUPS]
-% \@hldeston[GROUPS]
-% \@hldestoff[GROUPS]
-% \@@hlon
-% \@@hloff
-% \@@hldeston
-% \@@hldestoff
-%
-% Macros to switch hyperlinks / destinations on/off.
-%
-% The optional arg is the list of groups.  It can contain a star (*)
-% which will make the macros affect all groups (but not the low-level
-% macros \hlstart, \hlend and \hldest).
-%
-% \@hlon, \@hldeston, \@hloff and \@hldestoff will turn low-level
-% macros on/off only when they are used either without the optional
-% arg or with an empty `group' in the optional arg, otherwise only the
-% specified groups are affected.
-%
-% The single-`@' variants (\@hl...) are for the user.  In your macros,
-% if you want to (temporarily) turn low-level macros on/off, it's
-% better to use the double-`@' variants (\@@hl...), because they are
-% much faster and won't clobber \@optionalarg or anything else.
-%
-\def\@hlon{\@hlonoff@value@stub{hl}\@@hlon1 }%
-\def\@hloff{\@hlonoff@value@stub{hl}\@@hloff0 }%
-\def\@hldeston{\@hlonoff@value@stub{hldest}\@@hldeston1 }%
-\def\@hldestoff{\@hlonoff@value@stub{hldest}\@@hldestoff0 }%
-%
-\def\@hlonoff@value@stub#1#2#3{%
-  \def\hl@prefix{#1}%
-  \let\hl@on@empty#2%
-  \def\hl@value{#3}%
-  \expandafter\let\expandafter\hl@all@groups
-    \csname \hl@prefix @groups\endcsname
-  \@getoptionalarg\@finhlswitch
-}%
-%
-\def\@finhlswitch{%
-  \ifx\@optionalarg\empty
-    \hl@on@empty
-  \fi
-  % If we find an asterisk in the list, we have no choice but to
-  % finish the list and then call \@finhlswitch again, now with
-  % \hl@all@groups for the list of groups.
-  \let\hl@do@all@groups\relax
-%
-  \for\hl@group:=\@optionalarg\do{%
-    \ifx\hl@group\hl@asterisk@word
-      \let\@optionalarg\hl@all@groups
-      \let\hl@do@all@groups\@finhlswitch
-    \else
-      \ifx\hl@group\empty
-        \hl@on@empty
-      \else
-        \expandafter\ifx\csname\hl@prefix @on@\hl@group\endcsname \relax
-          \errmessage{Hyperlink group `\hl@prefix:on:\hl@group'
-                      is not defined}%
-        \fi
-        \ece\edef{\hl@prefix @on@\hl@group}{\hl@value}%
-      \fi
-    \fi
-  }%
-%
-  \hl@do@all@groups
-}%
-% Turn low-level macros on/off.
-\def\@@hlon{%
-  \let\hlstart\@hlstart
-  \let\hlend\@hlend
-}%
-\def\@@hloff{%
-  \def\hlstart##1##2##3{\leavevmode\ignorespaces}%
-  \let\hlend\relax
-}%
-\def\@@hldeston{%
-  \let\hldest\@hldest
-}%
-\def\@@hldestoff{%
-  \def\hldest##1##2##3{\ignorespaces}%
-}%
-%
-% Hyperlink drivers.
-%
-% \enablehyperlinks[OPTIONS] will enable hyperlinks.  OPTIONS is a
-% list of comma-separated options.  An option is one of the following:
-%
-%     idxexact      Point index links to exact locations of the term
-%     idxpage       Point index links to pages with the term (default)
-%     idxnone       No links for index entries
-%     <driver-name> Force the hyperlink driver
-%
-% If <driver-name> is omitted, appropriate driver will be detected, if
-% possible; if not, we fall back on `dvipdfm' (currently this means
-% `pdftex' when \ifpdf, and `dvipdfm' otherwise).
-\def\hl@idxexact@word{idxexact}%
-\def\hl@idxpage@word{idxpage}%
-\def\hl@idxnone@word{idxnone}%
-%
-\def\enablehyperlinks{\@getoptionalarg\@finenablehyperlinks}%
-\def\@finenablehyperlinks{%
-  \let\hl@selecteddriver\empty
-  % By default we generate `idxpage' index hyperlinks.
-  \def\hldest@place@idx{0}%
-  % Go through the option list.
-  \for\hl@arg:=\@optionalarg\do{%
-    \ifx\hl@arg\hl@idxexact@word
-      \def\hldest@place@idx{1}%
-    \else
-      \ifx\hl@arg\hl@idxnone@word
-        \def\hldest@place@idx{-1}%
-      \else
-        \ifx\hl@arg\hl@idxpage@word
-          \def\hldest@place@idx{0}%
-        \else
-          \let\hl@selecteddriver\hl@arg
-        \fi
-      \fi
-    \fi
-  }%
-  % Check the driver name.
-  \ifx\hl@selecteddriver\empty
-    % The user did not specify a driver, detect.
-    \ifpdf
-      \def\hl@selecteddriver{pdftex}%
-      \message{^^JUsing `pdftex' hyperlink driver.}%
-    \else
-      \def\hl@selecteddriver{dvipdfm}%
-      \message{^^JUsing `dvipdfm' hyperlink driver.}%
-    \fi
-  \else
-    % Check that the requested driver's initialization routine is
-    % available.
-    \expandafter\ifx\csname hldriver@\hl@selecteddriver\endcsname \relax
-      \errmessage{No hyperlink driver `\hl@selecteddriver' available}%
-    \fi
-  \fi
-  % Call the driver's initialization routine.
-  \csname hldriver@\hl@selecteddriver\endcsname
-  % Driver should not be changed later.
-  \def\@finenablehyperlinks{\errmessage{Hyperlink driver `\hl@selecteddriver'
-                                        already selected}}%
-  % Free memory taken up by the drivers.
-  \let\hldriver@nolinks\undefined
-  \let\hldriver@pdftex \undefined
-  \let\hldriver@dvipdfm\undefined
-  % The user can use these to turn the links / destinations on/off
-  % (see comments to the driver `nolinks').
-  \let\hloff\@hloff
-  \let\hlon\@hlon
-  \let\hldestoff\@hldestoff
-  \let\hldeston\@hldeston
-  % Turn everything on by default.
-  \hlon[*,]%
-  \hldeston[*,]%
-}%
-%
-% Driver `nolinks'.
-%
-% Select this driver to suppress any hyperlinks / destinations in your
-% document.
-%
-% NOTE:  selecting this driver is quite different from not selecting
-% any driver at all, or from selecting some driver and then turning
-% off links and destinations for the entire document with \hloff and
-% \hldestoff.
-%
-% The purpose of \hldestoff and \hloff is to mark (parts) of document
-% where links should never appear.  (Imagine you want to prevent a
-% cross-referencing macro from generating a link at a certain spot in
-% your document.)
-%
-% If instead you have prepared a document with links and just want to
-% compile a version without the links, it is better to select the
-% driver `nolinks'.  This will ensure that spacing and pagebreaking
-% will be the same as what you were getting with hyperlinks enabled.
-%
-% The reason for this is that hyperlinks are produced by \special
-% commands.  Each \special is placed inside a whatsit which may
-% introduce a legitimate breakpoint at places where none would exist
-% without the whatsit.  The macros \hldestoff and \hloff disable
-% hyperlink macros so drastically that no whatsits are produced.
-%
-% On the other hand, `nolinks' driver does not completely disable
-% hyperlink macros.  Instead, it defines them to write to the log
-% file (what gets written is not really important).  This will produce
-% the whatsits imitating the whatsits from the \special's.  (This
-% trick was borrowed from graphics bundle.)
-%
-% Another reason for using `nolinks' is that in horizontal mode
-% \hldest places destinations inside zero-width/height/depth boxes.
-% When you say \hldestoff, \hldest will omit both destination specs
-% and these boxes.  The missing boxes can cause typesetting to be
-% inconsistent with what you were getting with destinations enabled.
-% Again, `nolinks' driver helps here by defining \hldest to still
-% produce the empty boxes.
-%
-\def\hldriver@nolinks{%
-  \def\@hldest##1##2##3{%
-    \ifvmode
-      \write-1{\string\hldest: ##3}%
-    \else
-      \allowhyphens
-      \smash{\write-1{\string\hldest: ##3}}%
-      \allowhyphens
-    \fi
-    \ignorespaces
-  }%
-  \def\@hlstart##1##2##3{%
-    \leavevmode
-    \begingroup % Start the color group.
-    \write-1{\string\hlstart: ##3}%
-    \ignorespaces
-  }%
-  \def\@hlend{\write-1{\string\hlend}\endgroup}% End the group from \@hlstart.
-}%
-%
-% Driver `pdftex'.
-%
-\def\hldriver@pdftex{%
-\ifpdf % PDF output is enabled.
-  \def\hl@raw@word{raw}%
-  %
-  % Hyperlink destinations.
-  %
-  % Default type.
-  \def\hldest@type{xyz}%
-  % Set defaults for the options and tell \hl@set@opt what options we
-  % support.  (We do not define \hldest@opt@raise, \hl@opt@colormodel
-  % and \hl@opt@color, they are defined and used outside the drivers.)
-  \let\hldest@opt@width  \empty
-  \let\hldest@opt@height \empty
-  \let\hldest@opt@depth  \empty
-  \let\hldest@opt@zoom   \empty
-  \let\hldest@opt@cmd    \empty
-  % Multiplexer for all supported destination types.
-  \def\hldest@driver{%
-    % Special case for `raw' destinations.
-    \ifx\@hltype\hl@raw@word
-      \csname \hldest@opt@cmd \endcsname
-    \else
-      \pdfdest name{\@hllabel}\@hltype
-        \csname hldest@typeh@\@hltype\endcsname
-    \fi
-  }%
-  % Define handlers for each supported destination type.
-  \let\hldest@typeh@raw   \empty
-  \let\hldest@typeh@fit   \empty
-  \let\hldest@typeh@fith  \empty
-  \let\hldest@typeh@fitv  \empty
-  \let\hldest@typeh@fitb  \empty
-  \let\hldest@typeh@fitbh \empty
-  \let\hldest@typeh@fitbv \empty
-  \def\hldest@typeh@fitr{%
-    \ifx\hldest@opt@width  \empty \else width  \hldest@opt@width  \fi
-    \ifx\hldest@opt@height \empty \else height \hldest@opt@height \fi
-    \ifx\hldest@opt@depth  \empty \else depth  \hldest@opt@depth  \fi
-  }%
-  \def\hldest@typeh@xyz{%
-    \ifx\hldest@opt@zoom\empty \else zoom \hldest@opt@zoom \fi
-  }%
-  %
-  % Hyperlinks.
-  %
-  % Default type.
-  \def\hl@type{name}%
-  % We support `url' hyperlinks, so set the `url' group type.
-  \ifx\hl@type@url\empty
-    \def\hl@type@url{url}%
-  \fi
-  % Set defaults for the options and tell \hl@set@opt what options we
-  % support.
-  \let\hl@opt@width   \empty
-  \let\hl@opt@height  \empty
-  \let\hl@opt@depth   \empty
-  \def\hl@opt@bstyle  {S}%
-  \def\hl@opt@bwidth  {1}%
-  \let\hl@opt@bcolor  \empty
-  \let\hl@opt@hlight  \empty
-  \let\hl@opt@bdash   \empty
-  \let\hl@opt@pagefit \empty
-  \let\hl@opt@cmd     \empty
-  \let\hl@opt@file    \empty
-  \let\hl@opt@newwin  \empty
-  % Multiplexer for all supported link types.
-  \def\hl@driver{%
-    % Special case for `raw' links.
-    \ifx\@hltype\hl@raw@word
-      \csname \hl@opt@cmd \endcsname
-    \else
-      % See if we will construct a /BS spec.  We want to bother only
-      % if any of \hl@opt@bstyle, \hl@opt@bwidth and \hl@opt@bdash is
-      % not empty.
-      \let\hl@BSspec\relax % construct
-      \ifx\hl@opt@bstyle \empty
-        \ifx\hl@opt@bwidth \empty
-          \ifx\hl@opt@bdash \empty
-            \let\hl@BSspec\empty % don't construct
-          \fi
-        \fi
-      \fi
-      % Construct common preamble of a link.
-      \def\hlstart@preamble{%
-        \pdfstartlink
-          \ifx\hl@opt@width  \empty \else width  \hl@opt@width  \fi
-          \ifx\hl@opt@height \empty \else height \hl@opt@height \fi
-          \ifx\hl@opt@depth  \empty \else depth  \hl@opt@depth \fi
-          attr{%
-            \ifx\hl@opt@bcolor\empty\else /C[\hl@opt@bcolor]\fi
-            \ifx\hl@opt@hlight\empty\else /H/\hl@opt@hlight\fi
-            \ifx\hl@BSspec\relax
-              /BS<<%
-                /Type/Border%
-                \ifx\hl@opt@bstyle\empty\else /S/\hl@opt@bstyle\fi
-                \ifx\hl@opt@bwidth\empty\else /W \hl@opt@bwidth\fi
-                \ifx\hl@opt@bdash\empty \else /D[\hl@opt@bdash]\fi
-              >>%
-            \fi
-          }%
-      }%
-      % Call the handler.
-      \csname hl@typeh@\@hltype\endcsname
-    \fi
-  }%
-  % Link type handlers
-  \let\hl@typeh@raw\empty
-  \def\hl@typeh@name{\hlstart@preamble goto name{\@hllabel}}%
-  \def\hl@typeh@num{\hlstart@preamble  goto num \@hllabel}%
-  \def\hl@typeh@page{%
-    % PDF requires pages to start from 0, so adjust page number.
-    \count@=\@hllabel
-    \advance\count@ by-1
-    %
-    \hlstart@preamble
-    user{%
-      /Subtype/Link%
-      /Dest%
-        [\the\count@
-          \ifx\hl@opt@pagefit\empty/Fit\else\hl@opt@pagefit\fi]%
-    }%
-  }%
-  \def\hl@typeh@filename{\hl@file{(\@hllabel)}}%
-  \def\hl@typeh@filepage{%
-    % PDF requires pages to start from 0, so adjust page number.
-    \count@=\@hllabel
-    \advance\count@ by-1
-    %
-    \hl@file{%
-      [\the\count@ \ifx\hl@opt@pagefit\empty/Fit\else\hl@opt@pagefit\fi]%
-    }%
-  }%
-  \def\hl@file##1{%
-    \hlstart@preamble
-    user{%
-      /Subtype/Link%
-      /A<<%
-        /Type/Action%
-        /S/GoToR%
-        /D##1%
-        /F(\hl@opt@file)%
-        \ifx\hl@opt@newwin\empty \else
-          /NewWindow \ifcase\hl@opt@newwin false\else true\fi
-        \fi
-      >>%
-    }%
-  }%
-  \def\hl@typeh@url{%
-    \hlstart@preamble
-    user{%
-      /Subtype/Link%
-      /A<<%
-        /Type/Action
-        /S/URI%
-        /URI(\@hllabel)%
-      >>%
-    }%
-  }%
-  %
-  \def\@hlend{\pdfendlink\endgroup}% End the group from the \@hlstart.
-%
-\else % PDF output is not enabled.
-  \message{Warning: `pdftex' hyperlink driver: PDF output is
-           not enabled, falling back on `nolinks' driver.}%
-  \hldriver@nolinks
-\fi
-}%
-%
-% Driver `dvipdfm'.
-%
-\def\hldriver@dvipdfm{%
-  \def\hl@raw@word{raw}%
-  %
-  % Hyperlink destinations.
-  %
-  % Default type.
-  \def\hldest@type{xyz}%
-  % Set defaults for the options and tell \hl@set@opt what options we
-  % support.  (We do not define \hldest@opt@raise, \hl@opt@colormodel
-  % and \hl@opt@color, they are defined and used outside the drivers.)
-  \let\hldest@opt@left   \empty
-  \let\hldest@opt@top    \empty
-  \let\hldest@opt@right  \empty
-  \let\hldest@opt@bottom \empty
-  \let\hldest@opt@zoom   \empty
-  \let\hldest@opt@cmd    \empty
-  % Multiplexer for all supported destination types.
-  \def\hldest@driver{%
-    % Special case for `raw' destinations.
-    \ifx\@hltype\hl@raw@word
-      \csname \hldest@opt@cmd \endcsname
-    \else
-      % Construct common preamble of a destination.
-      \def\hldest@preamble{%
-        pdf: dest (\@hllabel) [@thispage
-      }%
-      % Call the handler.
-      \csname hldest@typeh@\@hltype\endcsname
-    \fi
-  }%
-  % Define handlers for each supported destination type.
-  \let\hldest@typeh@raw\empty
-  \def\hldest@typeh@fit{%
-    \special{\hldest@preamble /Fit]}%
-  }%
-  \def\hldest@typeh@fith{%
-    \special{\hldest@preamble /FitH
-      \ifx\hldest@opt@top\empty @ypos \else \hldest@opt@top \fi]}%
-  }%
-  \def\hldest@typeh@fitv{%
-    \special{\hldest@preamble /FitV
-      \ifx\hldest@opt@left\empty @xpos \else \hldest@opt@left \fi]}%
-  }%
-  \def\hldest@typeh@fitb{%
-    \special{\hldest@preamble /FitB]}%
-  }%
-  \def\hldest@typeh@fitbh{%
-    \special{\hldest@preamble /FitBH
-      \ifx\hldest@opt@top\empty @ypos \else \hldest@opt@top \fi]}%
-  }%
-  \def\hldest@typeh@fitbv{%
-    \special{\hldest@preamble /FitBV
-      \ifx\hldest@opt@left\empty @xpos \else \hldest@opt@left \fi]}%
-  }%
-  \def\hldest@typeh@fitr{%
-    \special{\hldest@preamble /FitR
-      \ifx\hldest@opt@left\empty @xpos\else\hldest@opt@left\fi\space
-      \ifx\hldest@opt@bottom\empty @ypos\else\hldest@opt@bottom\fi\space
-      \ifx\hldest@opt@right\empty @xpos\else\hldest@opt@right\fi\space
-      \ifx\hldest@opt@top\empty @ypos\else\hldest@opt@top \fi]}%
-  }%
-  \def\hldest@typeh@xyz{%
-    \begingroup
-      % Convert zoom factor:  12345 -> 12.345
-      \ifx\hldest@opt@zoom\empty
-        \count1=\z@ \count2=\z@
-      \else
-        \count2=\hldest@opt@zoom
-        \count1=\count2 \divide\count1 by 1000
-        \count3=\count1 \multiply\count3 by 1000
-        \advance\count2 by -\count3
-      \fi
-      \special{\hldest@preamble /XYZ
-        \ifx\hldest@opt@left\empty @xpos\else\hldest@opt@left\fi\space
-        \ifx\hldest@opt@top\empty @ypos\else\hldest@opt@top\fi\space
-        \the\count1.\the\count2]}%
-    \endgroup
-  }%
-  %
-  % Hyperlinks.
-  %
-  % Default type.
-  \def\hl@type{name}%
-  % We support `url' hyperlinks, so set `url' group type.
-  \ifx\hl@type@url\empty
-    \def\hl@type@url{url}%
-  \fi
-  % Set defaults for the options and tell \hl@set@opt what options we
-  % support.
-  \def\hl@opt@bstyle  {S}%
-  \def\hl@opt@bwidth  {1}%
-  \let\hl@opt@bcolor  \empty
-  \let\hl@opt@hlight  \empty
-  \let\hl@opt@bdash   \empty
-  \let\hl@opt@pagefit \empty
-  \let\hl@opt@cmd     \empty
-  \let\hl@opt@file    \empty
-  \let\hl@opt@newwin  \empty
-  % Multiplexer for all supported link types.
-  \def\hl@driver{%
-    % Special case for `raw' links.
-    \ifx\@hltype\hl@raw@word
-      \csname \hl@opt@cmd \endcsname
-    \else
-      % See if we will construct a /BS spec.  We want to bother only
-      % if any of \hl@opt@bstyle, \hl@opt@bwidth and \hl@opt@bdash is
-      % not empty.
-      \let\hl@BSspec\relax % construct
-      \ifx\hl@opt@bstyle \empty
-        \ifx\hl@opt@bwidth \empty
-          \ifx\hl@opt@bdash \empty
-            \let\hl@BSspec\empty % don't construct
-          \fi
-        \fi
-      \fi
-      % Construct common preamble of a link.
-      \def\hlstart@preamble{%
-        pdf: beginann
-          <<%
-            /Type/Annot%
-            /Subtype/Link%
-            \ifx\hl@opt@bcolor\empty\else /C[\hl@opt@bcolor]\fi
-            \ifx\hl@opt@hlight\empty\else /H/\hl@opt@hlight\fi
-            \ifx\hl@BSspec\relax
-              /BS<<%
-                /Type/Border%
-                \ifx\hl@opt@bstyle\empty\else /S/\hl@opt@bstyle\fi
-                \ifx\hl@opt@bwidth\empty\else /W \hl@opt@bwidth\fi
-                \ifx\hl@opt@bdash\empty \else /D[\hl@opt@bdash]\fi
-              >>%
-            \fi
-      }%
-      % Call the handler.
-      \csname hl@typeh@\@hltype\endcsname
-    \fi
-  }%
-  % Link type handlers.
-  \let\hl@typeh@raw\empty
-  \def\hl@typeh@name{\special{\hlstart@preamble /Dest(\@hllabel)>>}}%
-  \def\hl@typeh@page{%
-    % PDF requires pages to start from 0, so adjust page number.
-    \count@=\@hllabel
-    \advance\count@ by-1
-    %
-    \special{%
-      \hlstart@preamble
-      /Dest[\the\count@
-            \ifx\hl@opt@pagefit\empty/Fit\else\hl@opt@pagefit\fi]%
-     >>%
-    }%
-  }%
-  \def\hl@typeh@filename{\hl@file{(\@hllabel)}}%
-  \def\hl@typeh@filepage{%
-    % PDF requires pages to start from 0, so adjust page number.
-    \count@=\@hllabel
-    \advance\count@ by-1
-    %
-    \hl@file{%
-      [\the\count@ \ifx\hl@opt@pagefit\empty/Fit\else\hl@opt@pagefit\fi]%
-    }%
-  }%
-  \def\hl@file##1{%
-    \special{%
-      \hlstart@preamble
-      /A<<%
-        /Type/Action%
-        /S/GoToR%
-        /D##1%
-        /F(\hl@opt@file)%
-        \ifx\hl@opt@newwin\empty \else
-          /NewWindow \ifcase\hl@opt@newwin false\else true\fi
-        \fi
-      >>%
-     >>%
-    }%
-  }%
-  \def\hl@typeh@url{%
-    \special{%
-      \hlstart@preamble
-      /A<<%
-        /Type/Action
-        /S/URI%
-        /URI(\@hllabel)%
-      >>%
-     >>%
-    }%
-  }%
-  %
-  \def\@hlend{\special{pdf: endann}\endgroup}% End the group from \@hlstart.
-}%
-%
-% Internal hyperlink macros.
-%
-% \hl@define@eqlabel{LABEL} will define \hl@eqlabel to a non-empty
-% hyperlink label for an equation.  The idea is to generate
-% (hopefully) unique label in cases when LABEL is empty (e.g., when
-% user says `\eqdef{}').  To customize the autogenerated labels
-% redefine \phantomeqlabel.
-%
-\newcount\phantomeqnumber
-\def\phantomeqlabel{PHEQ\the\phantomeqnumber}%
-%
-\def\hl@define@eqlabel#1{%
-  % Make all definitions global so they are not shadowed by groups
-  % (\@eqdef depends on this).
-  \ifempty{#1}%
-    \global\advance\phantomeqnumber by1
-    \xdef\hl@eqlabel{\phantomeqlabel}%
-  \else
-    \gdef\hl@eqlabel{#1}%
-  \fi
-}%
-%
-% Cross-reference macros call hyperlink macros, so define them to
-% produce nothing by default.  However, we still want \hldest and
-% \hlstart to produce \leavevmode and/or \ignorespaces, to make
-% cross-reference macros consistent.  Note that this, strictly
-% speaking, makes cross-reference macros incompatible with
-% pre-hyperlink releases of eplain, in cases where paragraph is
-% started by a cross-reference macro.  It is quite unlikely though
-% that any problem will arise.
-\let\hldeston\relax \let\hldestoff\relax
-\let\hlon\relax \let\hloff\relax
-\@@hloff
-\@@hldestoff
-%
-%
-%
-%  Support for LaTeX packages under plain TeX.
-%
-% We use miniltx.tex from the LaTeX graphics collection and build on
-% it to provide package options support, package version check,
-% recursive package loading with \RequirePackage, proper handling of
-% \AtBeginDocument and \AtEndOfPackage.
-%
-% Much of the following was borrowed from LaTeX.
-%
-% The internal variables are quite a mess, so here is a hint:
-%
-%  - \usepkg@pkg, \usepkg@options, \usepkg@date are used by
-%    \usepackage to save its parameters.
-%
-%  - When \RequirePackage is called within a package, the above
-%    variables are saved in \usepkg@save@VAR@RECURSIONLEVEL, where
-%    VAR={pkg,options,date}, and RECURSIONLEVEL is incremented for
-%    each nested package inclusion.  This way the variables can be
-%    restored after the (nested) package will have been loaded.
-%
-%  - Options for package PACKAGE (no .sty extension) are accumulated
-%    in \usepkg@options@PACKAGE.
-%
-%  - For each declared option OPTION in package PACKAGE, we save the
-%    code which enables OPTION in \usepkg@option@PACKAGE@OPTION.
-%    There may be a star (`*') option declaration, the code from which
-%    will be used to process options not declared by the package
-%    (without it, an undeclared option will cause an error).
-%
-%  - For each loaded PACKAGE / FILE.EXT we declare \ver@PACKAGE.sty /
-%    \ver@FILE.EXT.  We use \ver@PACKAGE.sty to detect reloading
-%    of packages.  Some packages also use these macros.
-%
-%  - Calls to \AtBeginDocument accumulate the code in
-%    \usepkg@at@begin@document.  We will expand it at the end of the
-%    \beginpackages...\endpackages `environment'.
-%
-%  - Calls to \AtEndOfPackage accumulate the code in
-%    \usepkg@at@end@of@package.  We will expand it after the package
-%    is loaded.  To allow recursive package loading, \RequirePackage
-%    saves \usepkg@at@end@of@package analogous to \usepkg@pkg.
-%
-\newif\ifusepkg@miniltx@loaded
-\newcount\usepkg@recursion@level
-\def\usepkg@rcrs{\the\usepkg@recursion@level}%
-\let\usepkg@at@begin@document\empty
-\let\usepkg@at@end@of@package\empty
-\def\usepkg@word@autopict{autopict}%
-\def\usepkg@word@psfrag{psfrag}%
-% \beginpackages...\endpackages
-%
-% All packages must be loaded within this `environment' (a kind of
-% LaTeX's preamble).  This is so to give us a chance to expand the
-% accumulated \AtBeginDocument commands.  Usually, you will want to
-% restrict all \usepackage's to a single \beginpackages...\endpackages,
-% just like in LaTeX, where you load all packages within a (single)
-% preamble.
-\long\def\beginpackages#1\endpackages{%
-  \let\usepackage\real@usepackage
-  #1%
-  \usepkg@at@begin@document
-  \global\let\usepkg@at@begin@document\empty
-  \global\let\usepackage\fake@usepackage
-}%
-% \fake@usepackage
-%
-% This is what \usepackage is defined to outside of
-% \beginpackages...\endpackages `environment'.
-\def\fake@usepackage{\errmessage{You should not use \string\usepackage\space outside of^^J
-  \@spaces\string\beginpackages...\string\endpackages\space environment}%
-}%
-% \RequirePackage[OPTIONS]{PACKAGES}[YYYY/MM/DD]
-%
-% Save parameters for the package being loaded and call \usepackage to
-% load PACKAGES.  We depend on \usepackage to restore the saved
-% parameters.  We allow for nested calls to \RequirePackage.
-\def\eplain@RequirePackage{%
-  \global\ece\let{usepkg@save@pkg\usepkg@rcrs}\usepkg@pkg
-  \global\ece\let{usepkg@save@options\usepkg@rcrs}\usepkg@options
-  \global\ece\let{usepkg@save@date\usepkg@rcrs}\usepkg@date
-  \global\ece\let{usepkg@at@end@of@package\usepkg@rcrs}\usepkg@at@end@of@package
-  \global\advance\usepkg@recursion@level by\@ne
-  \real@usepackage
-}%
-% \usepackage[OPTIONS]{PACKAGES}[YYYY/MM/DD]
-%
-% Load each of the PACKAGES with OPTIONS, checking that the package
-% date is at least YYYY/MM/DD; if it is not, issue a warning.
-\let\usepackage\fake@usepackage
-\def\real@usepackage{\@getoptionalarg\@finusepackage}%
-\def\@finusepackage#1{%
-  \let\usepkg@options\@optionalarg
-  \ifempty{#1}%
-    \errmessage{No packages specified}%
-  \fi
-  % Load miniltx.tex, if it is not loaded.
-  \ifusepkg@miniltx@loaded \else
-    \testfileexistence[miniltx]{tex}%
-    \if@fileexists
-      \input miniltx.tex
-      \global\usepkg@miniltx@loadedtrue
-      % Redefine some macros from miniltx.tex
-      \global\let\RequirePackage\eplain@RequirePackage
-      \global\let\DeclareOption\eplain@DeclareOption
-      \global\let\PassOptionsToPackage\eplain@PassOptionsToPackage
-      \global\let\ExecuteOptions\eplain@ExecuteOptions
-      \global\let\ProcessOptions\eplain@ProcessOptions
-      \global\let\AtBeginDocument\eplain@AtBeginDocument
-      \global\let\AtEndOfPackage\eplain@AtEndOfPackage
-      \global\let\ProvidesFile\eplain@ProvidesFile
-      \global\let\ProvidesPackage\eplain@ProvidesPackage
-    \else
-      \errmessage{miniltx.tex not found, cannot load LaTeX packages}%
-    \fi
-  \fi
-  % Read the trailing optional arg (YYYY/MM/DD).
-  \@ifnextchar[%]
-    {\@finfinusepackage{#1}}%
-    {\@finfinusepackage{#1}[]}%
-}%
-%
-\def\@finfinusepackage#1[#2]{%
-  \edef\usepkg@date{#2}%
-  % Load each package from the list.  Do it outside the \for loop to
-  % avoid clashes with any \for loops executed by the package.
-  \let\usepkg@load@list\empty
-  \for\usepkg@pkg:=#1\do{%
-    \toks@=\expandafter{\usepkg@load@list}%
-    \edef\usepkg@load@list{%
-      \the\toks@
-      \noexpand\usepkg@load@pkg{\usepkg@pkg}%
-    }%
-  }%
-  \usepkg@load@list
-  % Restore parameters in case we were called from \RequirePackage.
-  \ifnum\usepkg@recursion@level>0
-    \global\advance\usepkg@recursion@level by\m@ne
-    \expandafter\let\expandafter\usepkg@pkg\csname usepkg@save@pkg\usepkg@rcrs\endcsname
-    \expandafter\let\expandafter\usepkg@options\csname usepkg@save@options\usepkg@rcrs\endcsname
-    \expandafter\let\expandafter\usepkg@date\csname usepkg@save@date\usepkg@rcrs\endcsname
-    \expandafter\let\expandafter\usepkg@at@end@of@package\csname usepkg@at@end@of@package\usepkg@rcrs\endcsname
-    % Free the memory.
-    \global\ece\let{usepkg@save@pkg\usepkg@rcrs}\undefined
-    \global\ece\let{usepkg@save@options\usepkg@rcrs}\undefined
-    \global\ece\let{usepkg@save@date\usepkg@rcrs}\undefined
-    \global\ece\let{usepkg@at@end@of@package\usepkg@rcrs}\undefined
-  \fi
-}%
-% Load one package.  We assume packages have `sty' extension.
-\def\usepkg@load@pkg#1{%
-  % Special cases for `autopict' and `psfrag' packages:
-  %   - `psfrag' is loaded by psfrag.tex.
-  %   - `autopict' is loaded by picture.tex, but the package file is
-  %      autopict.sty.
-  \def\usepkg@pkg{#1}%
-  \ifx\usepkg@pkg\usepkg@word@autopict
-    \testfileexistence[picture]{tex}%
-    \if@fileexists \else
-      \errmessage{Loader `picture.tex' for package `\usepkg@pkg' not found}%
-    \fi
-  \else
-    \ifx\usepkg@pkg\usepkg@word@psfrag
-      \testfileexistence[psfrag]{tex}%
-      \if@fileexists \else
-        \errmessage{Loader `psfrag.tex' for package `\usepkg@pkg' not found}%
-      \fi
-    \fi
-  \fi
-  % See if the package was loaded.  If it was, we just bail out.
-  % (Maybe we should skip reloading it/warn?  We don't want to go into
-  % checking that the package was first loaded with a subset of
-  % options which are requested now.)  \ProvidePackage and
-  % \ProvideFile define the macro \ver@PACKAGE.sty (see
-  % \eplain@pr@videpackage below).
-  \ifundefined{ver@\usepkg@pkg.sty}\else
-    \errmessage{Package `\usepkg@pkg' already loaded}%
-  \fi
-  \testfileexistence[\usepkg@pkg]{sty}%
-  \if@fileexists \else
-    \errmessage{Package `\usepkg@pkg' not found}%
-  \fi
-  % Construct option list for the package.  Include any options
-  % passed to us by \PassOptionsToPackage and \RequirePackage.
-  \expandafter\let\expandafter\temp\csname usepkg@options@\usepkg@pkg\endcsname
-  \ifx\temp\relax
-    \let\temp\empty
-  \fi
-  \ifx\temp\empty
-    \let\temp\usepkg@options
-  \else
-    \ifx\usepkg@options\empty \else
-      \edef\temp{\temp,\usepkg@options}%
-    \fi
-  \fi
-  \global\ece\let{usepkg@options@\usepkg@pkg}\temp
-  % For the duration of the package, we want any calls to \usepackage
-  % to be mapped to \RequirePackage, to allow nested package loads
-  % without clobbering up anything.  (Maybe packages never use
-  % \usepackage instead of \RequirePackage, but this won't hurt.)
-  \let\usepackage\eplain@RequirePackage
-  % Clear \AtEndOfPackage commands (can be non-empty during recursive
-  % package loading).
-  \global\let\usepkg@at@end@of@package\empty
-  % Load the package.  If the package asks to load other package,
-  % \RequirePackage will save our \usepkg@{pkg,options,date} and
-  % \AtEndOfPackage commands, and \usepackage will restore them after
-  % recursively loading that package, so we don't worry about our
-  % setup being clobbered.
-  \ifx\usepkg@pkg\usepkg@word@autopict
-    \input picture.tex
-  \else
-    \ifx\usepkg@pkg\usepkg@word@psfrag
-      \input \usepkg@pkg.tex
-    \else
-      \input \usepkg@pkg.sty
-    \fi
-  \fi
-  % Execute the accumulated \AtEndOfPackage commands, and reset them
-  % to free the memory.
-  \usepkg@at@end@of@package
-  \global\let\usepkg@at@end@of@package\empty
-  % Restore the `real' \usepackage definition.
-  \let\usepackage\real@usepackage
-  % Clear the option list for the loaded package (we won't load a
-  % second copy anyway).
-  \global\ece\let{usepkg@options@\usepkg@pkg}\undefined
-  % Set \Url@HyperHook for url.sty
-  \def\Url@HyperHook##1{\hlstart@impl{url}{\Url@String}##1\hlend@impl{url}}%
-  % We check package version in \ProvidePackage, before reading the
-  % rest of the package, so that in case of errors (which can be
-  % numerous) the warning hopefully comes before the errors.
-%  \@ifl@ter{sty}\usepkg@pkg\usepkg@date{}%
-%    {\message{Warning: you have requested package `\usepkg@pkg', version \usepkg@date,^^J
-%       \@spaces but only version `\csname ver@\usepkg@pkg.sty\endcsname' is available.}}%
-}%
-% \DeclareOption{OPTION}{CODE}
-%
-% Save CODE in `usepkg@option@PACKAGE@OPTION'.  Starred version is not
-% treated any different here, but when defined it will be used by
-% \ProcessOptions and \ExecuteOptions to process undeclared options.
-\def\eplain@DeclareOption#1#2{%
-  \toks@{#2}%
-  \expandafter\xdef\csname usepkg@option@\usepkg@pkg @#1\endcsname{\the\toks@}%
-}%
-% \PassOptionsToPackage{OPTIONS}{PACKAGES}
-%
-% Add OPTIONS to the option list for each of the PACKAGES.
-\def\eplain@PassOptionsToPackage#1#2{%
-  \ifempty{#1}\else
-    \for\usepkg@temp:=#2\do{%
-      \expandafter\let\expandafter\temp\csname usepkg@options@\usepkg@temp\endcsname
-      \ifx\temp\relax
-        \let\temp\empty
-      \fi
-      \ifx\temp\empty
-        \edef\temp{#1}%
-      \else
-        \edef\temp{\temp,#1}%
-      \fi
-      \global\ece\let{usepkg@options@\usepkg@temp}\temp
-    }%
-  \fi
-}%
-% \ExecuteOptions{OPTIONS}
-% \ProcessOptions
-%
-% \ExecuteOptions executes each option from OPTIONS, \ProcessOptions
-% executes each option from the option list for the current package.
-% If the star (`*') option is declared, it will be used to process
-% undeclared options; otherwise, undeclared option will cause an
-% error.
-\def\usepkg@exec@options#1{%
-  % The iterator \CurrentOption below was used purposely.  Some
-  % packages use it in the argument to \DeclareOption.
-  \for\CurrentOption:=#1\do{%
-    \expandafter\let\expandafter\usepkg@temp
-      \csname usepkg@option@\usepkg@pkg @\CurrentOption\endcsname
-%
-    \ifx\usepkg@temp\relax
-      % Option is not declared.  If a `default' option handler is
-      % declared, use it.
-      \expandafter\let\expandafter\temp\csname usepkg@option@\usepkg@pkg @*\endcsname
-      \ifx\temp\relax
-        \errmessage{Unknown option `\CurrentOption' to package `\usepkg@pkg'}%
-      \else
-        \temp
-      \fi
-    \else
-      % Option is declared.
-      \usepkg@temp
-    \fi
-  }%
-}%
-%
-\let\eplain@ExecuteOptions\usepkg@exec@options
-\def\eplain@ProcessOptions{%
-  \expandafter\usepkg@exec@options\csname usepkg@options@\usepkg@pkg\endcsname
-}%
-% \AtBeginDocument{CODE}
-% \AtEndOfPackage{CODE}
-%
-% miniltx.tex defines \AtBeginDocument to execute its parameter right
-% away, but some packages depend on \AtBeginDocument to be executed
-% after packages are processed.  So we redefine \AtBeginDocument to
-% accumulate its argument, to be executed by us at the end of
-% \beginpackages...\endpackages.  \AtEndOfPackage is not defined by
-% miniltx.tex at all; we define it similar to \AtBeginDocument.
-\def\usepkg@accumulate@cmds#1#2{%
-  \toks@=\expandafter{#1}%
-  \toks@ii={#2}%
-  \xdef#1{\the\toks@\the\toks@ii}%
-}%
-\def\eplain@AtBeginDocument{\usepkg@accumulate@cmds\usepkg@at@begin@document}%
-\def\eplain@AtEndOfPackage{\usepkg@accumulate@cmds\usepkg@at@end@of@package}%
-% \ProvidesFile{FILENAME.EXT}[VERSION]
-% \ProvidesPackage{PACKAGENAME}[VERSION]
-%
-% miniltx.tex defines \ProvidesFile and \ProvidesPackage to only log a
-% message.  We want to define \ver@PACKAGE.sty / \ver@FILENAME.EXT, as
-% we depend on these to know when a package/file has been loaded, and
-% some packages depend on them, too.
-\def\eplain@ProvidesPackage#1{%
-  \@ifnextchar[%]
-    {\eplain@pr@videpackage{#1.sty}}{\eplain@pr@videpackage#1[]}%
-}%
-\def\eplain@pr@videpackage#1[#2]{%
-  \wlog{#1: #2}%
-  % This will flag the package as loaded.
-  \expandafter\xdef\csname ver@#1\endcsname{#2}%
-%  \expandafter\edef\expandafter\temp{\csname usepkg@options@\usepkg@pkg\endcsname}%
-%  \message{^^JPackage:\usepkg@pkg^^JOptions:\usepkg@options^^J+ passed options:\temp^^J}%
-  % Check package version.
-  \@ifl@t@r{#2}\usepkg@date{}%
-    {\message{Warning: you have requested package `\usepkg@pkg', version \usepkg@date,^^J
-       \@spaces but only version `\csname ver@#1\endcsname' is available.}}%
-}%
-%
-\def\eplain@ProvidesFile#1{%
-  \@ifnextchar[%]
-    {\eplain@pr@videfile{#1}}{\eplain@pr@videfile#1[]}%
-}%
-\def\eplain@pr@videfile#1[#2]{%
-  \wlog{#1: #2}%
-  % This will flag the file as loaded.
-  \expandafter\xdef\csname ver@#1\endcsname{#2}%
-  % We don't check file version.  graphics calls \ProvideFile to
-  % \includegraphics, and it does not give any date at the beginning
-  % of #2, so checking the date will cause an error.
-}%
-% Check package version.  From LaTeX.
-\def\@ifl@ter#1#2{%
-  \expandafter\@ifl@t@r
-    \csname ver@#2.#1\endcsname
-}%
-\def\@ifl@t@r#1#2{%
-  \ifnum\expandafter\@parse@version#1//00\@nil<%
-        \expandafter\@parse@version#2//00\@nil
-    \expandafter\@secondoftwo
-  \else
-    \expandafter\@firstoftwo
-  \fi
-}%
-\def\@parse@version#1/#2/#3#4#5\@nil{#1#2#3#4 }%
-% Needed by some packages.
-\def\@spaces{\space\space\space\space}%
-\def\@inmatherr#1{%
-   \relax
-   \ifmmode
-     \errmessage{The command is invalid in math mode}%
-   \fi
-}%
-%
-%
-%
-\let\wlog = \@plainwlog
-\catcode`@ = \@eplainoldatcode
-%
-\def\fmtname{eplain}%
-\def\eplain{t}%
-{\edef\plainversion{\fmtversion}%
- \xdef\fmtversion{REPLACE-WITH-VERSION: REPLACE-WITH-DAY-MONTH-YEAR (and plain \plainversion)}%
-}%
-%
-% 
-% 
-% 
-% Local variables:
-% page-delimiter: "^% \f"
-% End: