-% Markup style infrastructure. \defmarkupstylesetup\INITMACRO will
-% define and register \INITMACRO to be called on markup style changes.
-% \INITMACRO can check \currentmarkupstyle for the innermost
-% style and the set of \ifmarkupSTYLE switches for all styles
-% currently in effect.
-\newif\ifmarkupvar
-\newif\ifmarkupsamp
-\newif\ifmarkupkey
-%\newif\ifmarkupfile % @file == @samp.
-%\newif\ifmarkupoption % @option == @samp.
-\newif\ifmarkupcode
-\newif\ifmarkupkbd
-%\newif\ifmarkupenv % @env == @code.
-%\newif\ifmarkupcommand % @command == @code.
-\newif\ifmarkuptex % @tex (and part of @math, for now).
-\newif\ifmarkupexample
-\newif\ifmarkupverb
-\newif\ifmarkupverbatim
-
-\let\currentmarkupstyle\empty
-
-\def\setupmarkupstyle#1{%
- \csname markup#1true\endcsname
- \def\currentmarkupstyle{#1}%
- \markupstylesetup
-}
-
-\let\markupstylesetup\empty
-
-\def\defmarkupstylesetup#1{%
- \expandafter\def\expandafter\markupstylesetup
- \expandafter{\markupstylesetup #1}%
- \def#1%
-}
-
-% Markup style setup for left and right quotes.
-\defmarkupstylesetup\markupsetuplq{%
- \expandafter\let\expandafter \temp \csname markupsetuplq\currentmarkupstyle\endcsname
- \ifx\temp\relax \markupsetuplqdefault \else \temp \fi
-}
-
-\defmarkupstylesetup\markupsetuprq{%
- \expandafter\let\expandafter \temp \csname markupsetuprq\currentmarkupstyle\endcsname
- \ifx\temp\relax \markupsetuprqdefault \else \temp \fi
-}
-
-{
-\catcode`\'=\active
-\catcode`\`=\active
-
-\gdef\markupsetuplqdefault{\let`\lq}
-\gdef\markupsetuprqdefault{\let'\rq}
-
-\gdef\markupsetcodequoteleft{\let`\codequoteleft}
-\gdef\markupsetcodequoteright{\let'\codequoteright}
-
-\gdef\markupsetnoligaturesquoteleft{\let`\noligaturesquoteleft}
-}
-
-\let\markupsetuplqcode \markupsetcodequoteleft
-\let\markupsetuprqcode \markupsetcodequoteright
-\let\markupsetuplqexample \markupsetcodequoteleft
-\let\markupsetuprqexample \markupsetcodequoteright
-\let\markupsetuplqverb \markupsetcodequoteleft
-\let\markupsetuprqverb \markupsetcodequoteright
-\let\markupsetuplqverbatim \markupsetcodequoteleft
-\let\markupsetuprqverbatim \markupsetcodequoteright
-
-\let\markupsetuplqsamp \markupsetnoligaturesquoteleft
-\let\markupsetuplqkbd \markupsetnoligaturesquoteleft
-
-% Allow an option to not replace quotes with a regular directed right
-% quote/apostrophe (char 0x27), but instead use the undirected quote
-% from cmtt (char 0x0d). The undirected quote is ugly, so don't make it
-% the default, but it works for pasting with more pdf viewers (at least
-% evince), the lilypond developers report. xpdf does work with the
-% regular 0x27.
-%
-\def\codequoteright{%
- \expandafter\ifx\csname SETtxicodequoteundirected\endcsname\relax
- \expandafter\ifx\csname SETcodequoteundirected\endcsname\relax
- '%
- \else \char'15 \fi
- \else \char'15 \fi
-}
-%
-% and a similar option for the left quote char vs. a grave accent.
-% Modern fonts display ASCII 0x60 as a grave accent, so some people like
-% the code environments to do likewise.
-%
-\def\codequoteleft{%
- \expandafter\ifx\csname SETtxicodequotebacktick\endcsname\relax
- \expandafter\ifx\csname SETcodequotebacktick\endcsname\relax
- % [Knuth] pp. 380,381,391
- % \relax disables Spanish ligatures ?` and !` of \tt font.
- \relax`%
- \else \char'22 \fi
- \else \char'22 \fi
-}
-
-% [Knuth] pp. 380,381,391, disable Spanish ligatures ?` and !` of \tt font.
-\def\noligaturesquoteleft{\relax\lq}
-
-% @point{}, @result{}, @expansion{}, @print{}, @equiv{}.
-%
-% Since these characters are used in examples, they should be an even number of
-% \tt widths. Each \tt character is 1en, so two makes it 1em.
-%
-\def\point{$\star$}
-\def\arrow{\leavevmode\raise.05ex\hbox to 1em{\hfil$\rightarrow$\hfil}}
-\def\result{\leavevmode\raise.05ex\hbox to 1em{\hfil$\Rightarrow$\hfil}}
-\def\expansion{\leavevmode\hbox to 1em{\hfil$\mapsto$\hfil}}
-\def\print{\leavevmode\lower.1ex\hbox to 1em{\hfil$\dashv$\hfil}}
-\def\equiv{\leavevmode\hbox to 1em{\hfil$\ptexequiv$\hfil}}
-
-% The @error{} command.
-% Adapted from the TeXbook's \boxit.
-%
-\newbox\errorbox
-%
-{\tentt \global\dimen0 = 3em}% Width of the box.
-\dimen2 = .55pt % Thickness of rules
-% The text. (`r' is open on the right, `e' somewhat less so on the left.)
-\setbox0 = \hbox{\kern-.75pt \reducedsf error\kern-1.5pt}
-%
-\setbox\errorbox=\hbox to \dimen0{\hfil
- \hsize = \dimen0 \advance\hsize by -5.8pt % Space to left+right.
- \advance\hsize by -2\dimen2 % Rules.
- \vbox{%
- \hrule height\dimen2
- \hbox{\vrule width\dimen2 \kern3pt % Space to left of text.
- \vtop{\kern2.4pt \box0 \kern2.4pt}% Space above/below.
- \kern3pt\vrule width\dimen2}% Space to right.
- \hrule height\dimen2}
- \hfil}
-%
-\def\error{\leavevmode\lower.7ex\copy\errorbox}
-