% $Id: macros.tex,v 1.4 2020/01/01 23:22:22 karl Exp $
% This is part of the book TeX for the Impatient.
% Copyright (C) 2003-2020 Paul W. Abrahams, Kathryn A. Hargreaves, Karl Berry.
% See file fdl.tex for copying conditions.
%
% Macros for typesetting TeX for the Impatient.
%
% These macros are being distributed without any warranty whatsoever.
% The level of commentary is that which we, the authors, found necessary
% for our own purposes.
%
% ==========================================================================
%
% The macros use the term `chapter' for what in the book is called
% a `section', `section' for the book's `subsection', etc. For purposes of
% defining macros it's convenient to think of the book as divided into
% chapters, but because of the nonsequential nature of the book we don't
% want to tell the readers that they are reading chapters.
% An embedded file should end with \byebye.
%
\begingroup
\ifx \macsin\relax
% In frontm.tex, we do \input macros several times, and we still want
% the \byebye at the end to end the job.
% So we \input inside a group in frontm, and make the assignment to
% \endinput local.
\aftergroup\let\aftergroup\byebye\aftergroup\endinput
\aftergroup\endinput % Don't read this file again.
\else
\global\let\byebye = \end
\global\let\macsin = \relax
\fi
\endgroup
% This must come before config.tex.
\input eplain
% Define configuration switches and then read their values.
%
\newif\ifcenterpage \centerpagetrue
\newif\ifcompletebook
\newif\iffinal % true for the 2000dpi copy
\newif\ifmsdos
\newif\ifedgetabs \edgetabstrue
\newif\ifdvi \dvitrue % true if we want a .dvi file
%\xrefwarningfalse
% The config file contains settings for flags, e.g.,
% \completebookfalse
% It can be empty as long as it exists.
\input config
\ifcompletebook \else\rewritetocfilefalse \fi
\edef\tempfile{\ifmsdos g:temp \else x \fi}
\ifx\setmodes\undefined\else\setmodes\fi % modify from command line input
% Certain defaults are forced by certain others.
%
\iffinal \centerpagetrue \edgetabstrue\fi
% Initial definitions. (These should come before \input fonts.)
%
\catcode`\@ = \letter % For the macro file only.
% We don't want register allocation information in the log,
% so we redefine the relevant macro from plain.tex.
\def\alloc@#1#2#3#4#5{\global\advance\count1#1 by 1
\ch@ck#1#4#2%
\allocationnumber=\count1#1 \global#3#5=\allocationnumber
}
% The fonts. This should come before defining the new character control
% sequences that follow.
%
\input fonts
\hyphenation{script-script base-line-skip no-base-line-skip line-skip
line-skip-limit max-dead-cycles output-penalty no-inter-line-skip
show-box-depth show-box-breadth if-hmode if-vmode if-mmode
back-spaces back-space par-indent tracing-on-line}
{
\catcode`\| = 0
\catcode`\\ = \other
|global|let|bsc = \ % \bsc is a true backslash character.
}
\let\\ = \bsc
\def\bslash{$\backslash$} % backslash suitable for printing
\let\shriek = !
\let\vbar = |
{
\catcode `\[ = 1 \catcode `\] = 2
\catcode `\{ = \other \catcode `\} = \other
\global\let\lbracechar = {
\global\let\rbracechar = }
]
\def\blbrace{{\bt \{}}
\def\brbrace{{\bt \}}}
{
\catcode`\ =\other% Notice no spaces at beginning of next line.
\gdef\otherspace{ }
}
\let\mathlbrace = \{ \let\mathrbrace = \}
{
\catcode `\[ = 1 \catcode `\] = 2
\catcode `\{ = \other \catcode `\} = \other
\gdef\{[\ifmmode\mathlbrace\else [\bt {]\fi]
\gdef\}[\ifmmode\mathrbrace\else [\bt }]\fi]
]
% These are for debugging (less drastically than \tracingall or \loggingall).
%
\def\tron{\tracingmacros=2 \tracingcommands=2 \tracingonline=1}
\def\troff{\tracingmacros=0 \tracingcommands=0}
% \pagebreak should always cause a break, even if the resulting
% page is empty.
%
\def\pagebreak{\null\vfill\eject}
% \linebreak causes a line break in chapter headings, but outside of that
% context we don't want it to do anything.
%
\let\linebreak = \relax
% Parameters.
%
\parskip = 0pt plus 0.3pt
\newdimen\codefuzz \codefuzz = 10pt % for \csdisplay, \example
\hbadness = 4000
\vbadness = 8000
\hfuzz = 0.1pt % as in plain TeX
\vfuzz = 0.1pt % as in plain TeX
\exhyphenpenalty = 0 % we don't mind these
\widowpenalty = 10000 % these are very bad
\clubpenalty = 10000 % these are very bad too
% Page margins.
%
% Note that the \newdimens can't be within an \if or a \def
% because \newdimen is an \outer macro (thanks to DEK).
%
\newdimen\insidemargin \newdimen\outsidemargin
\newdimen\topmargin \newdimen\bottommargin
\newdimen\headmargin
\newdimen\totalwidth \newdimen\totalheight
\newdimen\oddoffset \newdimen\evenoffset
\newif\ifnoheadline
% \totalwidth and \totalheight are the actual trim size of the book.
% \insidemargin, \outsidemargin, \topmargin, and \bottommargin are margins
% with respect to the pages of the book, not the draft 8 1/2 x 11 pages.
%
% This makes it so that we only have to cut twice on a page.
% 8.5" = 51.19125pc exactly.
% \totalwidth should = \outsidemargin + \insidemargin + \hsize.
%
\totalwidth = 7.375in % 44.4159375pc = 7 3/8".
\outsidemargin = 8pc
\insidemargin = 10pc
\hsize = \totalwidth
\advance \hsize by -\outsidemargin
\advance \hsize by -\insidemargin
% \hsize should now be 26.4159375pc
% Now that we know \hsize, we can set \parfillskip to eliminate (most)
% widows.
%
\parfillskip = .75\hsize plus .06\hsize minus .75\hsize
% \oddoffset and \evenoffset are the \hoffset values needed to
% align the left edge of the virtual page with the left edge of the
% draft paper (not the left edge of the book pages).
%
% The -1in below comes from the default margin, which the DVI driver must
% set at 1in. Odd pages are on the left, even on the right.
%
% First, align the left edge of the virtual page with the left edge of the
% draft page.
%
\oddoffset = -1in
\advance\oddoffset by \insidemargin
%
\evenoffset = -1in
\advance\evenoffset by \outsidemargin
% For centered pages, move the virtual page right by half the trim width.
%
\ifcenterpage
\dimen0 = 8.5in
\advance\dimen0 by -\totalwidth
\divide\dimen0 by 2
\advance\oddoffset by \dimen0
\advance\evenoffset by \dimen0
% For uncentered even-numbered pages, align the right edge of the virtual
% page with the right edge of the draft paper so that we can remove the trim
% of two-sided pages with a single cut.
%
\else
\advance\evenoffset by 8.5in
\advance\evenoffset by -\totalwidth
\fi
\hoffset = \oddoffset % First page is numbered one.
% Now for the vertical, which is simpler, since it doesn't vary from
% page to page.
% 11" = 66.2475pc exactly.
% \totalheight should = \topmargin + \bottommargin + \vsize.
%
\totalheight = 9.25in % 9 1/4" = 55.708125pc
\topmargin = 6pc % Distance from top of page to baseline of text line 1
\bottommargin = 6pc % Distance from last line to bottom of page.
\topskip = 2pc % Distance from top of \box255 to baseline of text line 1
% \vsize Distance from top of \box255 to last line of text.
% \headmargin Distance from top of \box255 to top of page
% We'll place the headline just above \box255
\headmargin = \topmargin \advance \headmargin by -\topskip
\vsize = \totalheight
\advance \vsize by -\headmargin
\advance \vsize by -\bottommargin
% \vsize should now be 46.708125pc
\voffset = -1in % align top of logical page with top of physical page
\advance \voffset by \headmargin
\ifcenterpage
\dimen0 = 11in
\advance\dimen0 by -\totalheight
\divide\dimen0 by 2
\advance\voffset by \dimen0
\fi
\topskip = 2pc % Distance from headline to first line of text.
% Other formatting parameters.
%
% The basic increments we'll use in the layout.
%
\def\setskip#1 = #2 {%
\dimen0 = #2\baselineskip
\csname #1skipamount\endcsname =
\dimen0 plus .33\dimen0 minus .25\dimen0
\ignorespaces
}
\newskip\greaterskipamount
\newskip\greatskipamount
\newskip\biggerskipamount
\newskip\medbigskipamount
\newskip\medsmallskipamount
\newskip\tinyskipamount
\setskip greater = 2.5
\setskip great = 2.0
\setskip bigger = 1.5
\setskip big = 1.0
\setskip medbig = .75
\setskip med = .5
\setskip medsmall = .375
\setskip small = .25
\setskip tiny = .125
\parindent = 1em
\newdimen\normalindent \normalindent = \parindent
\footnotemarkseparation = .16666em
\abovelistskip = \smallskipamount
\interitemskip = \tinyskipamount
\belowlistskip = \smallskipamount
\listleftindent = \parindent
% Displays involve text and math. We don't want as much flexibility in
% the glue as plain.tex sets.
%
\abovedisplayskip = \medsmallskipamount
\abovedisplayshortskip = 0pt plus 2pt
\belowdisplayskip = \medsmallskipamount
\belowdisplayshortskip = \belowdisplayskip
\newskip\intercapsuleskip \intercapsuleskip = .75\tinyskipamount plus 0.4pt
\newdimen\capsulehangindent \capsulehangindent = 2pc
\newskip\aboveconceptskip \aboveconceptskip = \bigskipamount
\newskip\abovesectionskip \abovesectionskip = \greaterskipamount
% No stretch or shrink below heads, according to A-W.
\newskip\belowsectionskip \belowsectionskip = 1\biggerskipamount
\newskip\abovesubsectionskip \abovesubsectionskip = \greatskipamount
\newskip\belowsubsectionskip \belowsubsectionskip = 1\bigskipamount
\newskip\abovedescriptionskip \abovedescriptionskip = \biggerskipamount
\newskip\belowdescriptionskip \belowdescriptionskip = \medskipamount
\newskip\explainskip \explainskip = \tinyskipamount
\newskip\exampleskip \exampleskip = \smallskipamount
\def\interexampleskip{\vskip\medsmallskipamount}
\def\tinyskip{\vskip\tinyskipamount}
% Space in which a symbol is shown in a columnated list of commands.
\newdimen\symbolspace \symbolspace = 14pt
% \colsindent is the indentation before material arranged in columns and
% displayed, as in the list of Greek letters.
\newskip\colsindent \colsindent = \parindent
% The indentation for page lists in the index that don't fit on one line.
\newdimen\indexpageindent \indexpageindent = 1pc
% The indentation for subsidiary entries in the index. (Should be less
% than \indexpageindent.)
\newdimen\indexlevelindent \indexlevelindent = .5pc
\newskip\codebaselineskip \codebaselineskip = \baselineskip
% Fill the previous page with blank space before a command.
%
\def\cmdbreak{\par\nobreak\vfil\penalty 1000\vfilneg\par}
% Penalties.
%
\newcount\conceptpenalty \conceptpenalty = -1500
\newcount\intercmdnamepenalty \intercmdnamepenalty = 300
\newcount\@intercmdnamepenalty \@intercmdnamepenalty = \intercmdnamepenalty
% The output routine.
%
\output = {%
\onepageout
%
% Odd pages are right-hand pages.
%
% Note \pageno has been incremented when we get here -- it now refers
% to the page number of the page about to be typeset, not the page
% that we just shipped out.
%
\ifodd\pageno % \onepageout advances \pageno.
\global\hoffset = \oddoffset
\global\intercmdnamepenalty = 10000
\else
\global\hoffset = \evenoffset
\global\intercmdnamepenalty = \@intercmdnamepenalty
\fi
}
\ifdvi\else\output={%
\setbox0=\box255\deadcycles=0
\advancepageno
\global\advance \truepage by 1
\ifnum\outputpenalty>-20000\else \dosupereject \fi
}
\fi
\def\onepageout{%
\shipout\vbox{%
\offinterlineskip % The page should have vertically abutting boxes.
\ifodd\pageno
\cropmargin = \insidemargin
\else
\cropmargin = \outsidemargin
\fi
\addcropmarks % Does not affect the position.
\ifcenterpage \addtruepage \fi
%
\ifedgetabs \ifodd\pageno \ifnoheadline\else
\edgetabs % Does not affect the position.
\fi\fi\fi
%
\vbox to 0pt{\vskip-\headmargin \vskip-3.5pc
\rightline{\sevenrm\timestamp}\vss}%
%
\smash{\line{\the\headline}}% Simplified \makeheadline.
\pagebody
\vskip 2\normalbaselineskip
% The footline is needed on one page (for an example).
\line{\the\footline}%
}%
% Now the rest from \plainoutput:
\advancepageno
\global\advance\truepage by 1
\ifnum\outputpenalty>-20000\else \dosupereject \fi
}
\footline = {\hfil}
% The headline always includes the name of the current chapter. This
% goes on the inside. If more information, such as the concept we're
% explaining, is included, it goes on the outside.
%
\headline = {%
% Produce the timestamp
\ifnoheadline
\hfil
\global\noheadlinefalse
\else
\let\\ = \ignorespaces
\ifodd \pageno % Right-hand page.
{\tenit \firstmark}\hfil {\tenbf \folio}%
\else % Left-hand page.
{\tenbf \folio}%
\hfil
{\tenit
\chaptername
\ifnum\pageno>0\ifback\else
\quad $\backslash$\quad\S\the\chapterno
\fi\fi
}%
\fi
\fi
}
% Sizes for cropmarks:
%
\newdimen\cropthick \cropthick = 0.4pt
\newdimen\crophsize \crophsize = 1pc
\newdimen\cropvsize \cropvsize = 1pc
\newdimen\cropoffset \cropoffset = .0625in
% Each of the following macros generates a quarter of a cropmark as
% a zero-size box at the center point of the cropmark.
% We want the cropmarks to be centered with respect to their thicknesses.
\def\vcropdown {\hbox to 0pt{%
\kern -.5\cropthick
\vbox to 0pt{%
\vskip \cropoffset
\hrule width\cropthick depth\cropvsize height0pt
\vss}%
\kern -.5\cropthick}%
}
\def\vcropup {\hbox to 0pt{%
\kern -.5\cropthick
\vbox to 0pt{%
\vss
\hrule width\cropthick depth\cropvsize height0pt
\vskip \cropoffset}%
\kern -.5\cropthick}%
}
\def\hcropright{\rlap{\kern\cropoffset\smash{%
\vrule width\crophsize depth .5\cropthick height .5\cropthick}}}
\def\hcropleft{\llap{\smash{%
\vrule width\crophsize depth .5\cropthick height .5\cropthick}%
\kern\cropoffset}}
% \cropmargin will be set to the left margin on the current page.
%
\newdimen\cropmargin
\def\cropline#1{\moveleft\cropmargin\hbox to \totalwidth{#1}}
% \addcropmarks adds the cropmarks to a page while leaving everything else
% alone. It assumes we're positioned at the top of the page.
\def\addcropmarks{%
\vbox to 0pt{%
\offinterlineskip % contextually redundant but precautionary
\vskip -\headmargin % to get to logical top of page
\ifcenterpage
\cropline{\hcropleft\vcropup \hfil \vcropup\hcropright}
\else
\cropline{\hfil \vcropdown}%
\fi
\vskip\totalheight
\ifcenterpage
\cropline{\hcropleft\vcropdown \hfil \vcropdown\hcropright}%
\else
\cropline{\hcropright\hfil\hcropleft\vcropup\vcropdown\hcropright}%
\fi
\vss
}}
% \addtruepage adds a small page number near the upper right cropmark.
%
\newcount\truepage \truepage = 1
\def\addtruepage{%
\vbox to 0pt{\vskip -\headmargin\vskip -2pc
\moveleft\cropmargin\hbox to \totalwidth{%
\twelvebf
\quad\TeX\ for the Impatient\hss
N\raise 3.3pt\hbox{o} \the\truepage\quad}%
\vss}%
}
% The mark information is output by \markinfo.
%
% We can use a different mark, e.g., a shorter heading, by calling
% \changemark.
%
\newtoks\shortmark \shortmark = {}
\newif\ifchangemark
\def\markinfo#1{%
\ifchangemark
\mark{\the\shortmark}\changemarkfalse
\else
\mark{#1}%
\fi
}
\def\changemark#1{\shortmark = {#1}\changemarktrue}
% ``Tabs'' down the side of the book.
% Say \nextedgetab to move the thing down to the next.
% Say \edgetabsfalse to turn them off.
%
\newcount\numtabs \numtabs = 7
\newdimen\edgetabjump \edgetabjump = 0pt
\def\nextedgetab{%
\advance\edgetabjump by \edgetabdepth
}
\def\settabdepth#1{%
\edgetabdepth = #1
\setbox\tabbox = \vbox to \edgetabdepth{%
\leaders
\vbox{\vskip \edgespacing
\hrule width\edgetabwidth height0pt depth\edgethick}%
\vfil}
}
\newskip\bigtab \newskip\smalltab
\newskip\edgetabdepth
\newbox\tabbox
\bigtab = \totalheight \divide\bigtab by \numtabs
\smalltab = .4\bigtab % five smalls make two bigs
\newdimen\edgetabin \edgetabin = .25in
\newdimen\edgetabbleed \edgetabbleed = .25in
\newdimen\edgetabwidth
\edgetabwidth = \edgetabin
\advance \edgetabwidth by \edgetabbleed
\newdimen\edgethick \edgethick = .3pt % line thickness
\newdimen\edgespacing \edgespacing = .9pt % line spacing
\def\edgetabs{\vbox to 0pt{%
\vskip-\headmargin
\vskip\edgetabjump
\hbox{%
\hskip \hsize
\hskip\outsidemargin
\hskip-\edgetabin
\copy\tabbox
}%
\vss
}}
% We can simplify \pagecontents (which is called by \pagebody) somewhat,
% since we don't have \topinserts.
%
\def\pagecontents{%
\unvbox255 % The main page contents.
%
\ifvoid\footins\else % Footnotes are present.
\vskip\skip\footins
\footnoterule
\unvbox\footins
\fi
}
% The command chapters had a mini-index at the bottom of right-hand
% pages. These definitions are the way to put entries into it.
%
% \minref generates a reference for the mini-index, and prints the
% reference on the page, also.
%
\def\minref#1{%
#1% Print it on the page.
% That's it, now.
}
% Mini-index entry without printing the argument on the page.
% Just ignore the argument now.
%
\def\minrefs#1{%
\ignorespaces
}
% This is used for producing the concept mini-index.
%
\def\minrefsdelim#1\endmark{\minrefs{#1}}
% One last insertion-oriented thing:
% we always want numbered footnotes, as defined in eplain.
% We'll do them in 8-point type.
%
\let\@plainfootnote = \footnote
\let\footnote = \numberedfootnote
\everyfootnote = {\footnotefonts}
% The \margin macro produces a marginal note at the same level as its call.
% It should only be used in a paragraph or in the main vertical list.
% It is nullified when we're printing the final copy.
%
\def\margin#1{%
\ifhmode
\vadjust{\printmarginnote{#1}}%
\else
\dimen0 = \prevdepth
\prevdepth = -1000pt
\printmarginnote{#1}%
\prevdepth = \dimen0
\fi
\ignorespaces
}
\def\printmarginnote#1{%
\hbox to 0pt{%
\hskip 1.1\hsize
\vbox to 0pt{%
\everypar = {}% Don't inherit hanging indentation.
\hsize = 1in \rightskip = 0pt plus 1fil \noindent \sevenrm
\let\tt = \eighttt
\parfillskip = 0pt plus 1fil
\baselineskip = 8pt #1%
\vss
}%
\hss
}%
}
%\iffinal
\iftrue
\def\margin#1{\ignorespaces}
\fi
% Stuff to preserve page breaks inserted for the 2nd printing.
% This macro takes one ``argument''.
%
\def\secondprinting{\afterassignment\finishsecondprinting \toks0 = }
\def\finishsecondprinting{\the\toks0}
% Parts of the book.
%
%
% Chapters.
%
\let\chaptername = \empty
\newcount\chapterno
\def\chaprule{\vrule depth3\baselineskip height1.5pc width1pt}
% Chapter openings should not have headlines.
% The text of each chapter starts on a right-hand page in the final
% book. The facing page has an illustration. This means that if the
% previous chapter ended on a left-hand (i.e., even) page, we have to
% eject an extra blank page.
%
\outer\def\chapter#1 \par{%
\ifcompletebook % Don't do the blank pages for proof copies.
\blankpage % the illustration page
% The first real chapter starts on page 1.
\ifnum\pageno < 0 \pageno = 1 \fi
\fi
%
\def\chaptername{#1}%
\advance\chapterno by 1
%
\setbox0 = \hbox{\chapternumeralfont
\kern1pt
\expandafter\kernchapno\the\chapterno\empty
\kern3pt}%
\vglue 0pt % But we get a \topskip of 2pc now.
\nointerlineskip
\leftline{%
\ifback\else
\vtop{%
\copy0
\vskip6pt
\hrule width\wd0 height2.2pc
}%
\kern 16pt
\fi
\chapterfonts % to get \baselineskip now
\chaprule
\kern 6pt
\vtop{%
\def\linebreak{\hfil\break}%
\noindent \chaptername}%
}%
\vskip 6pc plus.5pc minus.5pc
\noheadlinetrue
\toks0=\expandafter{\chaptername}
\edef\writechaptertoc{%
\noexpand\writenumberedtocentry{chapter}{\the\toks0}{\the\chapterno}%
}%
\writechaptertoc
%
% Use chaptername as first A-head (or only one).
\mark{\chaptername}%
\footnotenumber = 0 % Number footnotes from 1 in each chapter.
\beginit{CHAPTER}%
\noindent
\ignorespaces
}
\def\endchapter{%
\mark{\chaptername}% Use chapter name on last blank recto page
\vfil\eject % be sure everything's out before testing for recto
\ifodd\pageno
\message{Chapter ends on a verso page.}%
\blankpage
\fi
\endit{CHAPTER}%
}
%
% \blankpage creates a blank page with no headline.
% In the final book, it just advances the page number.
% For the web edition, the blank pages serve no purpose except to keep
% the indexing correct. I didn't want to rerun the index.
%
\def\blankpage{%
\iffinal
\advancepageno
\global \advance \truepage by 1
\else
\noheadlinetrue\pagebreak
\fi
}
% This hokey little macro kerns between the numerals in the chapter
% number. We want to kern more between `11' then otherwise; also, we
% want to remove the extra space before the chapter number, and after
% `11'.
%
\def\kernchapno#1#2{%
\ifx\empty#2\else \kern-3pt \fi
#1%
\ifx\empty#2\else
\if1#2%
\kern-.1em
\else
\kern-.05em
\fi
\fi
#2%
\if 1#2\kern-.1em\fi
}
% Sections.
%
\newif\ifheading % Avoid breaking after a heading.
% get section numbers for the fdl only, since it has internal references.
\let\fdlkludge=\empty
% The heading flag is turned on by headings and turned off
% at the start of a description.
%
\outer\def\section#1 \par{%
\par % be sure we're in vertical mode
\saveskip = \lastskip % will be 0 if no skip
\cmdbreak
\combineskips\abovesectionskip
\dimen0 = 2.5\baselineskip \advance\dimen0 by -\topskip
\vskip -\dimen0
\vglue \dimen0
%
{\sectionfonts \leftline{\fdlkludge #1}}%
%
\markinfo{#1}%
\writetocentry{section}{#1}%
\nobreak
% Don't go into horizontal mode within the command descriptions.
%
\vskip\belowsectionskip
\ifcommands \else \noindent \fi
\headingtrue
\everypar = {\headingfalse \global\everypar = {}}%
% only gets executed for \par in horizontal mode
\ignorespaces
}
% Subsections. We don't want a break at the glue if we were preceded by
% a \nobreak.
%
\def\subsection#1 \par{%
\par % be sure we're in vertical mode
\saveskip = \lastskip % will be 0 if no skip
\ifheading % Did we just have \section?
\nobreak
\fi
\combineskips\abovesubsectionskip
\dimen0 = 2.5\baselineskip \advance\dimen0 by -\topskip
\vskip -\dimen0
\vglue \dimen0
%
{\subsectionfonts
\leftline{\vrule width.5em height1.2ex depth.2ex \enspace #1}}%
\writetocentry{subsection}{#1}%
\nobreak
% Don't go into horizontal mode within the command descriptions.
\vskip\belowsubsectionskip
\ifcommands \else \noindent \fi
\headingtrue
\everypar = {\headingfalse \global\everypar = {}}%
% only gets executed for \par in horizontal mode
\ignorespaces
}
% \combineskips combines the current skip (#1) with the previous skip
% (which must be in \saveskip), and effectively skips by the larger of
% the two.
%
\newskip\saveskip
\def\combineskips#1{\ifdim\saveskip<#1\vskip-\saveskip \vskip#1\fi}
% List macros.
%
% We want to use different names than eplain.
%
\let\ulist = \unorderedlist
\let\endulist = \endunorderedlist
%
\let\olist = \numberedlist
\let\endolist = \endnumberedlist
\let\compact = \listcompact
% The \noindent here keeps us from getting indentation on the first line.
% It also makes the display into a `short' display, FYI.
% The \belowdisplayskip and \abovedisplayskip glue are inserted by the
% display.
%
\long\def\display#1{%
\ifvmode \noindent \fi
$$\vtop{\everypar = {}\hsize = \displaywidth
\parfillskip = 0pt plus 1fil % don't worry about widows
\noindent #1\par\global\savedepth = \prevdepth}$$%
\endgraf
\prevdepth = \savedepth
}
% \vdisplay is like \display, except it's for vertical mode material. Use it
% to avoid an unwanted initial lineskip.
%
\long\def\vdisplay#1{%
\ifvmode \noindent \fi
$$\vtop{\everypar = {}\hsize = \displaywidth
\parfillskip = 0pt plus 1fil % don't worry about widows
#1\par\global\savedepth = \prevdepth}$$%
\endgraf
\prevdepth = \savedepth
}
% Indexing.
% Derived from Knuth's manmac macros.
%
\newwrite\index
\immediate\openout\index = \jobname.idx
\newif\ifsilent
% We need ^ to be active temporarily, while we define it.
%
{ \catcode`\^ = \active
%
\gdef^{%
\ifmmode
\let \nextaction = \sp
\else
\let \nextaction = \beginindexref
\begingroup
\catcode `| = \other \catcode `^ = \other
\fi
\nextaction
}}
\def\beginindexref{\futurelet\next\checksilence}
{% And for here, we need ^ to be deactivated
\catcode `^ = \other
\gdef\checksilence{%
\if ^\next
\silenttrue \let\nextaction = \secondhat
\else
\silentfalse \let\nextaction = \checkbar
\fi
\nextaction
}
% Eat the `^' that we saw would be the next token.
%
\gdef\secondhat^{\checkbar}
} % end scope where ^ is \other
\def\checkbar{\futurelet\next\iswitch}
% Here we start reading the text of the actual index entry;
% we've determined whether it's silent or not.
%
% We handle the following cases:
% ^{alpha} and ^^{alpha}
% ^|alpha| and ^^|alpha|
% ^|\alpha| and ^^|\alpha|
%
% When this is called, \next is either `|' or `{'.
%
\def\iswitch{%
\ifx |\next
\let \nextaction = \checkbackslash
\else
\let \nextaction = \normalidx
\fi
\nextaction
}
\def\checkbackslash|{%
% within |...| we allow anything (but another |)
\deactivate \catcode `\ = \other
\futurelet\next\litidx
}
% The thing after the ^ is a |. We have further checking to do -- is
% the next character a \?
%
{ % reverse \ and /
\catcode`\/ = 0
\catcode`\\ = \other
/gdef/litidx{%
/if \/next
/expandafter/litidxA
/else
/expandafter/litidxB
/fi
}
% The thing being indexed starts with a \.
%
/gdef/litidxA \#1|{%
/ctsidxref{#1}%
/litidxswitch{/\#1}%
}
% The thing being indexed is just a word.
%
/gdef/litidxB #1|{%
/ttidxref{#1}%
/litidxswitch{#1}%
}
}% end reversal of \ and /
% The thing after the ^ is not a |.
%
\def\normalidx#1{%
\ifsilent
\aftergroup\ignorespaces
\else
#1%
\fi
\idxref{#1}%
\endgroup % group started by \iswitch.
}
\def\litidxswitch#1{%
\ifsilent
\aftergroup\ignorespaces
\else
{\tt #1}%
\fi
\endgroup % group started by \iswitch.
}
% Indexing macros for external use.
% \idxref generates an index entry for #1. If #1 contains any control
% sequences, they are treated literally.
%
\def\idxref#1{\indexwrite{#1}N\ignorespaces}
% For creating an index entry for control space.
{\catcode `\ =\other
\gdef\blankidxref{\ctsidxref{ }}
}
% I removed this macro from eplain because \csname works as well, but
% since the macros below are already written to use it ...
\def\@tokstostring#1{\@ttsA#1 \@ttsmarkA}%
\let\tokstostring=\@tokstostring
\def\@ttsA#1 #2\@ttsmarkA{%
\@ifempty{#1}\else
\@ttsB #1\@ttsmarkB
\@ifempty{#2}\else
\@spacesub\@ttsA#2\@ttsmarkA
\fi
\fi
}%
\def\@ttsB#1{%
\ifx #1\@ttsmarkB\else
\string #1%
\expandafter\@ttsB
\fi
}%
\def\@ttsmarkB{\@ttsmarkB}% should never be expanded
%
\def\@spacesub{+}%
\let\spacesub = \@spacesub
%
\def\@ifempty#1{\@@ifempty #1\@emptymarkA\@emptymarkB}%
\def\@@ifempty#1#2\@emptymarkB{\ifx #1\@emptymarkA}%
\def\@emptymarkA{\@emptymarkA}% Again, so \ifx won't complain.
% #1 is the index term, #2 is the reference as in
% Diacritical mark, see accent.
\def\idxsee#1#2{%
\begingroup
\def\spacesub{\otherspace}%
\edef\nextaction{\write\index{\tokstostring{#1}::N::*\tokstostring{#2}}}%
\nextaction
\ignorespaces
\endgroup}
% \ttidxref generates an index entry for #1 in the program font.
% If #1 contains any control sequences, they are treated literally.
%
\def\ttidxref#1{\indexwrite{#1}T\ignorespaces}
% \ctsidxref generates an index entry for a control sequence. #1
% should not have a preceding backslash, so that the proper call for
% indexing \alpha is \ctsidxref{alpha}.
%
\def\ctsidxref #1{\indexwrite{#1}C\ignorespaces}
% \indexchar is needed to generate index entries for three especially
% difficult single characters: {, }, and \. They are blank-delimited.
%
\def\indexchar{\begingroup \deactivate \indexcharA}
\def\indexcharA#1 {\indexwrite{#1}T\endgroup}
% \pix indicates that the next index entry is a principal one.
%
\newif\ifpix
\def\pix{\global\pixtrue}
% \bix and \eix indicate that the next index entry begins or ends a
% range of pages.
%
\newif\ifbix \def\bix{\bixtrue}
\newif\ifeix \def\eix{\eixtrue}
% #1 is the text of the entry, #2 is N (normal), T (typewriter) or
% C (control sequence) or `cs' for now.
%
\def\indexwrite#1#2{\begingroup
\def\spacesub{\otherspace}%
\edef\tts{\tokstostring{#1}}%
\edef\nextaction{\write\index{\tts::#2::\noexpand\number\noexpand\pageno
\ifpix P\fi\ifbix B\fi\ifeix E\fi}}%
\nextaction
\global\pixfalse \global\bixfalse \global\eixfalse
\endgroup}
{\catcode `\^ = \other \gdef\twocarets{^^}}
% For generating index entries with weird characters, we need to deactivate
% them: { } blank \ and substitute [ ] ! for { } \ . \recat does this.
% It should be enclosed in a group (which must end in `]').
\def\recat{%
\aftergroup\ignorespaces
\catcode `\! = 0 \catcode `[ = 1 \catcode `] = 2
\catcode `\ = \other \deactivate
}
% Macros for the front matter.
%
% Space at the top of the frontmatter pages.
%
\def\sinkage{\vglue 7pc \relax}
% And at the top of the backmatter pages.
%
\def\backsinkage{\vglue 2pc \relax}
% \frontchapter doesn't care if we're on an even page or an odd page.
%
\def\frontchapter#1 \par{%
\def\chaptername{#1}%
\leftline{%
\chapterfonts
\chaprule
\kern 6pt
\vtop{%
\def\linebreak{\hfil\break}%
\noindent \chaptername}%
}%
\vskip 4pc
\noheadlinetrue
% Use chaptername as first A-head (or only one)
\mark{\chaptername}%
\noheadlinetrue
\noindent \ignorespaces
}
% We are called from inside a group, so we can redefine the \toc... macros.
%
\def\shortcontents{{%
\firsttoctrue
\backfalse
\shorttocfonts
\let\tocchapterentry = \shorttocchapter
\let\tocsectionentry = \gobblethree
\let\tocsubsectionentry = \gobblethree
\halign{\hfil\strut##&\strut ##\hfil\cr
\readtocfile
\crcr}}%
\pagebreak
\global\backfalse
}
% #1 is the chapter name, #2 the chapter number, #3 the page number.
%
\def\shorttocchapter#1#2#3{%
\ifback\else#2\quad $\backslash$\quad\fi\qquad
\raise3pt\hbox{\vrule height2pt width4pt depth2pt}$\,\,$#3\cr
}
% Yes, we read the entire contents (several pages) as one alignment.
%
\def\contents{{%
\firsttoctrue
\backfalse
\tocfonts
\interlinepenalty = 100
\halign{\hfil\strut##&\strut ##\hfil\cr
\readtocfile
\crcr}}%
\pagebreak
% We want to end the contents on a recto page, even if it's blank
\ifodd\pageno\pagebreak\fi % leaves us on an even page.
\global\backfalse
}
\newif\iffirsttoc
\def\tocchapterentry#1#2#3{%
\iffirsttoc
\global\firsttocfalse
\else
\noalign{\penalty-1000 \bigskip\smallskip}%
\fi
%
\ifback\else\bf#2\quad $\backslash$\quad\fi
&\bf#1\qquad\raise3pt\hbox{\vrule height2pt width4pt depth2pt}%
$\,\,$#3\cr
\noalign{\nobreak\vskip2pt}%
}
\def\tocsectionentry#1#2#3{%
\noalign{\penalty-500 \vskip\medsmallskipamount}%
&\it #1\quad \openbox$\,\,$\rm #3\cr
}
\def\tocsubsectionentry#1#2#3{%
&\qquad #1\quad $\cdot\,$#3\cr
}
\def\openbox{\ht0 = 1.75pt \dp0 = 1.75pt \wd0 = 3.5pt
\raise 2.75pt \makeblankbox{.2pt}{.2pt}%
}
\newif\ifback
% \ifback is true when we're doing the table of contents and are about
% to do the back matter. It is also true just before we do the back matter
% chapters (really, only the index).
%
\def\backmatter{\write\tocfile{\noexpand\setback}\backtrue}
\def\setback{\noalign{\bigskip\global\backtrue}}
% Macros for the examples chapter.
%
% \doexamples is called with the name of the examples file
% Each example is ended by ::: (including the last one)
% A line starting with ~ is executed in the output (without the ~)
% but dropped from the input.
%
% Within the input, ! is an escape character, but {} are not recognized.
% This provides a limited control sequence capability, which is sufficient
% for delimited macros and therefore for cross-references (see \xrefdelim).
% !! stands for !.
%
\def\endmark{:::}
\newif\ifnotatend \newif\ifnotatendfile \newif\iftildeline
\newread\exfileA \newread\exfileB \newwrite\exfileC
\newcount\examplenumber
\def\doexamples#1{%
% Here we assume that two read-only openings of the same file are OK.
\immediate\openin\exfileA = #1
\immediate\openin\exfileB = #1
\loop
\advance\examplenumber by 1
\reader
\ifx\holder\empty \notatendfilefalse \else \notatendfiletrue \fi
\ifnotatendfile
\dooneexample
\repeat
}
% We want control sequences to be executed as the input of each example
% is formatted, but we don't want to execute them for the output of each
% example until we generate that output with an \input command.
% Therefore, we treat ! differently for \holder, which produces example
% input, and \holderA, which produces example output.
%
% We can't say \global\immediate\read, but \immediate is implied with \read.
%
\def\reader{{\deactivate
\catcode`\! = \other % To execute control sequences on \input.
\catcode`\^^M = 9 \global\read\exfileA to \holder
%
\catcode`\! = 0 % To execute control sequences right away.
\obeyspaces \global\read\exfileB to \holderA
}%
}
\def\dooneexample{{%
% We want to mention \! in one of the examples:
\edef\examplenum{\numbername\examplenumber}%
\immediate\openout\exfileC = \tempfile
\catcode`\| = \other % No literal code in these examples.
\chardef\! = `\! % !! means a literal ! character.
% Collect the input page, as it is to be printed, in a box
% At the same time, write out each line to \exfileC
% We make the box 0pt tall to avoid problems with overfull pages.
\setbox\xmpinput = \vbox to 0pt{%
%
\baselineskip = \codebaselineskip
\loop
\ifx\endmark\holder \notatendfalse \else\notatendtrue \fi
\ifnotatend
\expandafter\tildecheck\holder \empty \marker
\iftildeline\else
\leftline{\tt\frenchspacing \holderA \thinspace}%
\immediate\write\exfileC{\holder}%
\fi
\reader
\repeat
\vss % reduce height to 0pt
}% end \vtop
\immediate\closeout\exfileC
{%
\maxdepth = \maxdimen % allow long input
\vfill\eject
\catcode`\! = 0
\restoreplainTeX
{%
\let\eject = \relax \input\tempfile
% Every example ends with \bye, but \bye is disabled in the main text.
\vfill\par\penalty-10000
\global\footline = {\hfil}%
}%
\box\xmpinput
}%
}}
{
\catcode `\~ = \other % So the \ifx works.
\gdef\tildecheck#1#2\marker{%
\ifx #1~%
\immediate\write\exfileC {#2}\tildelinetrue
\else
\tildelinefalse
\fi
}
}
% This definition is more or less repeated verbatim in the first example
% in xmptext.tex.
%
\def\xmpheader #1/#2{%
{\exampletitlefonts \leftline{Example #1:\quad \bi#2}}%
\vglue .5\baselineskip
\count255 = \pageno
\xdef\examplepage{\number\count255}%
\markinfo{Example #1: #2}
\ifrewritetocfile
\write\tocfile{\string\tocsectionentry{#2}{}{\examplepage}}%
\fi
}
% Let's number examples automatically; it makes it easier to move them
% around and add new ones.
\def\xmpnum{\number\examplenumber}
\newbox\xmpinput
% \negthin lets us put `\!' in examples.
\def\negthin{\ifmmode \mskip-\thinmuskip \else \char`\\ \char`\! \fi}
\def\xmpheaddef{see \xref{xmphead}}
\def\restoreplainTeX{%
% Restore plain TeX's parameters (except for \hsize and \hoffset).
\parindent = 20pt
\parskip = 0pt plus 1pt
\parfillskip = 0pt plus 1fil
\hfuzz = 0.1pt
\hbadness = 1000
\abovedisplayskip=12pt plus 3pt minus 9pt
\abovedisplayshortskip=0pt plus 3pt
\belowdisplayskip=12pt plus 3pt minus 9pt
\belowdisplayshortskip=7pt plus 3pt minus 4pt
\everymath = {}%
\everydisplay = {}%
\centereddisplays
\let\vfootnote = \@plainvfootnote
\let\footnote = \@plainfootnote
\let\tenrm = \oldtenrm
\textfont0 = \tenrm
\rm
\ignorespaces
}%
% Macros for the concepts chapter.
%
%
% Start off the chapter.
%
\def\beginconcepts{\openout\conceptfile = \jobname.ccs }
\def\endconcepts{\closeout\conceptfile}
\newwrite\conceptfile
% \concept produces a concept heading and also generates a crossreference
% suitable for the mini-index. It even works for concepts with several words
% or containing control sequences like `\ascii'.
%
\def\concept#1 \par{%
\par
%k \cmdbreak
\penalty\conceptpenalty\vskip\aboveconceptskip
%k \vskip 0pt plus 1pt % allow a little more stretch
\noindent
% generate the index entry
\ifconceptindex \else \global\indextoks = {\idxref{#1}}\fi
\conceptindexfalse
\pix\bix\the\indextoks
%
{\bt \let\it=\bti \unskip\null #1.\hskip1em plus.2em minus.2em }%
\markinfo{#1}%
\xrdef{#1}%
\write\conceptfile{\string\doconcept{#1}{\number\pageno}}%
\beginit{CONCEPT}%
\nobreak
\ignorespaces
}
\def\endconcept{%
\par % always go to vertical mode here
\eix\the\indextoks
\endit{CONCEPT}%
\ignorespaces
}
\def\doconcept#1#2{\hbox{#1\quad #2}}
% Sometimes we want to index a concept under some other name than the
% concept name, e.g., indexing `delimiter' as `delimiters'. The
% \conceptindex macro lets us do this.
%
\newif\ifconceptindex
\newtoks\indextoks
\def\conceptindex#1{%
\conceptindextrue
\global\indextoks = {\idxref{#1}}%
\ignorespaces
}
% Commands for cross-referencing within the concepts chapter.
% Each refterm has the form {a} or {a:b}, where b is the term to
% actually reference (e.g., \refterm{\PlainTeX:\plainTeX}).
%
\def\refterm#1{%
\reftermA #1:\endmark % Parse the stuff.
\expandafter\minrefsdelim\termtoref\endmark
\relax % Cancel the \ignorespaces.
}%
\def\reftermA#1:{\reftermfirst{#1}\futurelet\next\reftermB}
\def\reftermB#1\endmark{\ifx\endmark \next \else \reftermsecond#1\fi}
\def\reftermfirst#1{#1\def\termtoref{#1}}
\def\reftermsecond#1:{\def\termtoref{#1}}%
% The defining sentence for a concept.
%
\def\defterm#1{{\it #1\/}}
% This macro prints the single page that will go on the back cover.
%
\def\printconceptpage{%
% Make sure this is considered an odd page.
\ifodd\pageno\else\blankpage\fi
\noheadlinetrue
\advance\hsize by 2pc
\vglue2pc % Plus a \topskip of 2pc.
{\sectionfonts \leftline{List of concepts}}%
\vskip\belowsectionskip
{\conceptpagefonts
\parindent=0pt
\makecolumns 94/3:
\input \jobname.ccs
\vfil
% Put the `logo' at the bottom of the page.
\rightline{\thisbook}%
}%
\eject
}
% Macros for the commands chapters.
%
% \ifcommands is true when we're within \begindescriptions ...
\newif\ifcommands
% \begindescriptions should be called to start the actual control sequences.
%
\outer\def\begindescriptions{\beginit{DESCRIPTIONS}%
% The following definitions are local to this chapter.
%
\let\example = \commandexample
\let\endexample = \endcommandexample
\interlinepenalty = 50
%
\commandstrue
\ignorespaces
}
% The \endgroup that \enddescriptions does must come after the page
% break, so the last page of descriptions will get a mini-index.
%
\def\enddescriptions{%
\vskip -\lastskip % undo the skip created by \enddesc
\endit{DESCRIPTIONS}%
\ignorespaces
}
% Begin or end the description of a control sequence or group thereof.
%
\def\begindesc{%
\par % force vertical mode
\saveskip = \lastskip % will be 0 if no skip
\ifheading % Did we just have \section or \subsection?
\nobreak
\else
\cmdbreak
\fi
\combineskips\abovedescriptionskip
\headingfalse
\beginit{DESCRIPTION}%
\beginit{COMMANDS}%
% Each command name is set as a paragraph (for reasons I don't
% remember, \leftline doesn't work because of the way the manuscript
% was typed), and so \clubpenalty will be the penalty at the
% interline glue (see p.96).
\clubpenalty = \intercmdnamepenalty
\parfillskip = 0pt plus 1fil
\ignorespaces
}
\def\enddesc{%
\nobreak % if we need a break, we'll get it from the next group opener
\vskip\belowdescriptionskip
\endit{DESCRIPTION}%
\ignorespaces
}
% Begin the explanation of a control sequence. Don't break at the
% space above the explanation, or the interline glue before the first line.
%
\def\explain{%
\par
\endit{COMMANDS}%
\nobreak \vskip\explainskip
\interlinepenalty = 50
\nobreak \noindent
\ignorespaces
}
% Here is how \example looks in the text:
% \example
% ...
% |
% \produces
% ...
% \endexample
%
% repeated an indefinite number of times.
%
% We want to set the code of an example in a box so as to prevent it from
% being broken across pages. By using \vtop we assure that the code is the
% right distance from the `Example:' line. In order to keep the `produces:'
% the right distance from the last code line, we save the depth of that code
% line and then fool TeX into thinking that the \vtop has that depth by
% assigning it to \prevdepth. If we didn't do this, the last line of the code
% would be too close to the `produces:' (as indeed it was in earlier versions
% of the book.
%
\newdimen\savedepth
{\makeactive|
\gdef\commandexample{% a.k.a. \example, inside \begindescriptions.
\cmdbreak\vskip\exampleskip
\leftline{\it Example:}%
\nobreak % At the interline glue.
\beginit{EXAMPLE}%
\parfillskip = 0pt plus 1fil
\hbox\bgroup\hskip\parindent\vtop\bgroup
\begincs
\let | = \endcode
\advance\hsize by -\parindent
\parindent = 0pt
\bgroup\obeywhitespace
}}%
\def\endcode{%
\egroup % end \obeywhitespace group
\par\global\savedepth=\prevdepth
\egroup % end inner \vbox
\egroup % end outer \hbox
\prevdepth = \savedepth
\ignorespaces
}
% \dproduces should be used when the following material is a math
% display.
%
\newif\ifexampledisplay
\def\dproduces{\global\exampledisplaytrue \produces}
\newif\ifproduces
% \produces puts its material into a vbox so it won't be broken.
% The material starts in VERTICAL MODE! It uses the plainTeX conventions
% except that \parindent is 0pt.
\def\produces{%
\producestrue
\ifodd\pageno \par \nobreak \else \cmdbreak\fi
\vskip\tinyskipamount
\noindent {\it produces\ifexamplelog\ in the log\examplelogfalse\fi :}%
\vadjust{\nobreak}% At the interline glue.
\ifexampledisplay
\centereddisplays
\else
\par\nobreak
\advance\hsize by -\parindent
\savedepth = \prevdepth
\nointerlineskip
\hbox\bgroup\hskip\normalindent
\vtop\bgroup \restoreplainTeX \parindent = 0pt
\prevdepth = \savedepth
\fi
}%
% we need another ``produces'' form for when a command puts things in
% the log. In this case, the produces text also ends with a |.
%
\newif\ifexamplelog
{\makeactive|
\gdef\logproduces{\examplelogtrue\produces
\begincs
\def |{\endcode\producesfalse}%
% Every line is set as a paragraph, so we get one \parindent for free.
% But we also did \advance\leftskip in \produces, so now we have two.
% We only want one.
\advance\leftskip by -\parindent
\bgroup\obeywhitespace
}}%
\def\nextexample{\endexample\interexampleskip\example}
\def\endcommandexample{%
\par % force vertical mode, set previous paragraph
\ifproduces \ifexampledisplay \global\exampledisplayfalse \else
\global\savedepth = \prevdepth
\egroup % Matches the \vtop in either the \produces or the \example.
\egroup % Matches the \hbox in \producesbox.
\global\producesfalse
\par
\prevdepth = \savedepth
\fi\fi
\endit{EXAMPLE}%
\ignorespaces
}
\def\see{%
\ifodd\pageno\nobreak\fi % don't put at the top of a verso page
\vskip -\lastskip % should be \belowdescriptionskip
\bigskip
\noindent
{\tenbi \spaceskip = 3.33pt plus 2pt minus 1.1pt
\parfillskip = 0pt plus 1fil
See also: %k \hskip 1em plus .5em minus .25em
}%
\ignorespaces
}%
\newif\ifxref \xreftrue
% \aux acts as a prefix to a \cts command, specifying that a
% cross-reference should not be generated.
%
\def\aux{\xreffalse}
% So does \easy, which prints a hand, pointing at the control sequence.
% (The hand font doesn't define an em.)
%
\newif\ifeasy
\let\easy = \easytrue
\def\testeasy{\ifeasy\llap{\hand\ \kern 6pt}\easyfalse\fi}
% \cts typesets the beginning of a control sequence description, and
% generates an index entry and cross-reference definition for it. The
% control sequence name must be delimited by a blank, since there may be
% parameters that follow. The control sequence name can contain special
% characters; they are deactivated. The initial \ must be omitted.
%
\def\cts{\begingroup \deactivate \ctsA}
\def\ctsA#1 {\endgroup \ctsB{#1}}
\def\ctsB#1#2{%
\ctsbasic{\\#1}{#2}%
\ifxref \ctsxrdef{#1}\else \xreftrue \fi
\pix\ctsidxref{#1}%
}
% \ctsx is like \cts, but separates the control sequence name and the
% text by more space. (`x' for `extra')
%
\def\ctsx{\begingroup \deactivate \ctsxA}
\def\ctsxA#1 {\endgroup \ctsxB{#1}}
\def\ctsxB#1#2{%
\ctsbasic{\\#1}{\quad #2}%
\ifxref \ctsxrdef{#1}\else \xreftrue \fi
\pix\ctsidxref{#1}%
}
% \ctscol is like \cts, but doesn't start a new paragraph. It's used in
% in columns of cs's and their explanations.
%
\def\ctscol#1 #2{%
{\bt \\#1}\quad #2%
\ifxref \ctsxrdef{#1}\else \xreftrue \fi
\pix\ctsidxref{#1}%
}
% \ctsbasic does the actual printing of a cs name. It's needed on its
% own for `\ '. It does not generate any index or cross-reference
% entries. #1 is the command name, #2 some (possibly empty) text to go
% next to it.
%
\def\ctsbasic#1#2{%
\par
\nobreak % At the \parskip glue the \noindent will produce.
\noindent\testeasy {{\bt #1}\space #2}%
}
% \ctsxrdef generates a control sequence cross-reference definition.
% For example, `\ctsxrdef{@star}' generates a cross-reference definition
% for `\@star'.
%
\def\ctsxrdef#1{\expandafter\xrdef\csname#1\endcsname}
% \ctsact prints an active character #1 and generates an index entry
% for it. #1 is blank-delimited. \ctsact does not generate a
% cross-reference definition.
%
\def\ctsact{\begingroup \deactivate \ctsactA}
\def\ctsactA#1 {\endgroup
\ctsbasic{#1}{}%
\pix\ttidxref{#1}}
% \ctspecial prints a control sequence #1 and generates an index
% entry for it. #1 is blank-delimited. \ctspecial does not
% automatically generate a cross-reference definition, and so it's used
% for things like \newbox and \%.
%
\def\ctspecial{\begingroup \deactivate \ctspecialA}
\def\ctspecialA#1 {\endgroup
\ctsbasic{\\#1}{}%
\pix\ctsidxref{#1}%
}
% \ctspecialx is like \ctspecial, but leaves more space after its
% argument. We want ` and ' to come from cmtt, instead of Optima, so we
% call \mapquotes before reading the argument. This only affects the \`
% and \' descriptions.
%
\def\ctspecialx{\begingroup \deactivate \mapquotes \ctspecialxA}
\def\ctspecialxA#1 {\endgroup
\ctsbasic{\\#1}{}\quad
\pix\ctsidxref{#1}%
}
% \ctsdisplay has a blank-delimited argument consisting of a control
% sequence such as alpha. It produces $\alpha$ followed by \alpha.
%
\def\ctsdisplay#1 {\basicdisplay {$\csname #1\endcsname$}{\\#1}%
\ifxref\ctsxrdef{#1}\else\xreftrue\fi \pix\ctsidxref {#1}}
% \ctsdoubledisplay has a blank-delimited argument consisting of a
% control sequence such as bigvee. It produces $\bigvee$ and
% $\big\bigvee$ followed by \bigvee.
%
\def\ctsdoubledisplay#1 {
{%
\symbolspace = 42pt
\basicdisplay{$\csname #1\endcsname\quad
\displaystyle\csname #1\endcsname$\ddstrut}%
{\\#1}%
}%
\ifxref\ctsxrdef{#1}\else\xreftrue\fi
\pix\ctsidxref{#1}%
}
\def\ddstrut{\vrule width0pt height15pt depth11pt}
% \ctsydisplay displays a control symbol. #1 is a single character,
% which may be active. #2 is the cross-reference label,
% blank-delimited.
%
\def\ctsydisplay{\begingroup \deactivate\catcode`\|=\other \ctsydisplayA}
\def\ctsydisplayA#1 #2 {\endgroup
\basicdisplay{$\csname\string#1\endcsname$}{\\#1}%
\ifxref \ctsxrdef{#2}\else \xreftrue \fi
\pix\ctsidxref{#1}%
}
% \actdisplay displays an active character. #1 is the character, and
% #2 is the cross-reference label, blank-delimited.
%
\def\actdisplay{\begingroup\catcode `\|=\other\actdisplayA}
\def\actdisplayA#1 #2 {\endgroup
\basicdisplay{$#1$}{\string#1}%
\ifxref \xrdef{#2}\else \xreftrue \fi
\pix\ttidxref{#1}%
}
% \basicdisplay does the actual typesetting of a control sequence name.
% for inside displays.
%
\def\basicdisplay#1#2{\testeasy\hbox to \symbolspace{#1\hfil}{\bt #2}}
% Printing parameter and table entry headings.
%
\def\param#1{\printparam{#1}{parameter}}
\def\tblentry#1{\printparam{#1}{table entry}}
\def\printparam#1#2{\hskip1.5em [\kern3pt \<#1> #2\kern2pt]}
% Required braces.
%
\def\rqbraces#1{\{\hskip2pt#1\hskip2pt\}}
% Printing rulers.
%
\def\1{\vrule height 0pt depth 2pt}
\def\2{\vrule height 0pt depth 4pt}
\def\3{\vrule height 0pt depth 6pt}
\def\4{\vrule height 0pt depth 8pt}
\def\ruler#1#2#3{{$\vcenter{\hrule\hbox{\4#1}}\,\,\rm#2\,{#3}$}}
\def\doruler{\par \noindent\ruler}
\def\tick#1{\hbox to .125in{\hfil#1}}
\def\8{\tick\1\tick\2\tick\1\tick\3\tick\1\tick\2\tick\1\tick\4}
% Macros for the capsule summary chapter.
%
\def\begincapsum{\beginit{CAPSULE SUMMARY}%
\let\bt = \tentt
\bigskip
}
\def\endcapsum{\endit{CAPSULE SUMMARY}}
\newbox\@primitivebox \setbox\@primitivebox = \hbox{\tt *}
\newif\ifcs
\def\capline{\begingroup \deactivate\catcode `\| = \other \caplineA}
\def\caplineA#1 {\endgroup
\begingroup
\catcode `@ = \letter % for constructing labels
\caplineB{#1}%
}
% Parameters of \caplineB:
% #1 name of control sequence
% #2 description
% #3 * or empty
% #4 xref or xref1:xref2 or empty
\def\caplineB#1#2#3#4{%
\ifempty {#4}\temptrue\else\tempfalse\fi
% \iftemp needed to avoid \if ... \else ... \fi nesting problems
\ifcs
\toks0 = {\caplineout{\\#1}{#2}{#3}}%
\iftemp
\toks1 = \expandafter{\csname #1\endcsname}%
\else
\toks1 = {#4}%
\fi
\edef\nextaction{\the\toks0 {\the\toks1}}%
\nextaction
\ctsidxref {#1}%
\else
% The \space makes one-character entries line up nicely.
\caplineout{\space #1}{#2}{#3}{#4}%
\ttidxref {#1}%
\fi
\endgroup
}
\newif\iftemp
% In a few cases we have two cross-references for a single control
% sequence.
%
\newif\ifcstwo
\def\capac{\cstwofalse\csfalse\capline}
\def\capactwo{\cstwotrue\csfalse\capline}
\def\capcs{\cstwofalse\cstrue\capline}
\def\capcstwo{\cstwotrue\cstrue\capline}
% \caplineout produces an output line (or several lines) for the capsule
% summary. #1 is the command text, #2 is the description, #3 is either * or
% empty, and #4 is the cross-reference label.
%
\def\caplineout#1#2#3#4{%
\setbox0 = \ifempty {#3}\box\voidb@x \else \copy\@primitivebox\fi
\vskip\intercapsuleskip
% If we use \vbox here, a multi-line summary at the top of a page
% will cause \topskip to disappear.
%
\vtop{\noindent \hangindent = \capsulehangindent
\spaceskip = 3.33pt plus 2pt minus 1.5pt
\rightskip = 0pt plus 4em % a little more stretch
\parfillskip = 0pt plus 1fil
\llap{\box0}{\bt #1}% Bold typewriter for the cs name.
\quad \hskip 0pt plus 1pt minus 1pt
#2\unskip\
(\ifcstwo \tworefs #4:\else \xref{#4}\fi)%
}%
\par
}
\def\tworefs#1:#2:{\xref{#1}, \xref{#2}}
% Macros for printing the index.
%
% Set up to print it.
%
\def\beginindex{%
\doublecolumns
\beginit{THE INDEX}
\markinfo{\chaptername}%
\indexfonts
\parindent = 0pt
\def\pp##1{{\it ##1}} % Principal entry.
\def\c{,\thinspace\allowbreak}%
\def\ic{,\quad}
\def\see##1{.\quad{\it See} ##1 }
\def\seealso##1{\hfil\break{\it See also} ##1 }
\let\r = \romannumeral
\raggedright
}
\def\endindex{\endit{THE INDEX}\singlecolumn}
% #1 is the level of this index entry minus 1 (i.e., 0 for a main
% entry), #2 is the index term, #3 is the kind of term
% (T for ttfont, C for control sequence, N for normal), and
% #4 is the list of pages. The page list can have \pp (principal
% entry)in it, and each page is separated by \c.
%
\def\indexentry#1#2#3#4{%
\beginit{INDEX ENTRY}%
\leftskip = #1\indexpageindent
\par
\leavevmode
\hangindent = \indexlevelindent
\ifx #3T%
{\tt #2}% Typewriter.
\else \ifx #3C%
{\tt \llap{\\}#2}% Control sequence.
\else
% in normal entries, \b and \e enclose a group. ({ and } don't work.)
{\let \b = \bgroup \let \e = \egroup #2}%
\fi\fi
#4% The list of pages.
\par
\endit{INDEX ENTRY}%
}
% Nah, let's forget printing the initial.
%
\def\indexgroup#1{%
\bigskip
}
% Code formatting.
%
%
% Turn off normally special characters.
%
\def\deactivate{%
\catcode`\\ = \other \catcode`\{ = \other \catcode`\} = \other
\catcode`\$ = \other \catcode`\& = \other \catcode`\# = \other
\catcode`\% = \other \catcode`\~ = \other \catcode`\^ = \other
\catcode`\_ = \other
}
% It is convenient to have |...| mean print the ... verbatim, except for !.
% (But | should just be a vertical bar in math mode.) This should be
% used only for inline code; returns inside |...| become spaces.
%
\catcode`\| = \active
\def|{%
\ifmmode
\vert
\else
\begingroup
\obeyspaces
\begincs
\let| = \endgroup
\fi
}
% \csdisplay is similar, but it inserts glue before and after.
% It also is ended by |, so we have to redefine that.
%
\def\csdisplay{%
\par
\nobreak % don't break above displays
\vskip\abovedisplayskip
\begingroup
\interlinepenalty = 10000
\obeywhitespace
\begincs
\def|{\endgroup\vskip\belowdisplayskip \noindent\ignorespaces}%
}
% \begincs does the setup for verbatim printing. It does not confine
% its effects to a group.
%
\def\begincs{%
\hfuzz = \codefuzz
\parfillskip = 0pt plus 1fil
\parskip = 0pt % don't stretch interparagraph space within code displays
\catcode`\! = 0
\let\! = \exclam
\let\| = \verticalbar
\let\$ = $%
\let\. = \empty % Use !. to end a control sequence to be executed.
\def\-{\discretionary{-}{}{}}% but allow explicit discretionary hyphens
\tt \deactivate
}
\chardef\exclam = `\!
\chardef\verticalbar = `\|
% In math mode we want vertical bars and exclamation points to be
% regular characters again.
%
\everymath = {\setmathchars}
\everydisplay = {\setmathchars}
\leftdisplays
\def\setmathchars{%
\catcode`\| = \other \catcode`\! = \other
\let\{ = \lbrace \let\} = \rbrace
}
% Some miscellanous macros.
%
\def\anatomy{anatomy of \TeX}
\def\ascii{{\ninerm ASCII}}
\def\asciichar#1{$\langle \rm #1\rangle$}
\def\bblfile{{\tt .bbl} file}
\def\bibfile{{\tt .bib} file}
\def\bstfile{{\tt .bst} file}
\def\didotpt{did\^ot point}
\def\dvifile{{\tt .dvi} file}
\def\em{\thinspace {\rm em}}
\def\emph#1{{\it #1}\itcorr} % Emphasize.
\def\ftp{{\tt ftp}}
\def\gffile{{\tt .gf} file}
\def\hand{{\handfont \char"2B}}
\def\ifatest{{\tt \\if} test}
\chardef\inches = "7D
\def\knuth#1{#1 of \texbook}
\let\Metafont = \MF
\def\Mperiod.{$M$\kern-1.6pt.}
\def\Mprimecomma,{$M'$\kern-3.5pt,}
\def\Mprimeperiod.{$M'$\kern-2.5pt.}
\def\mud{\thinspace {\rm mu}} % can't use \mu; it'a a Greek letter!
\def\newTeX{new \TeX}
\def\p{p.\thinspace}
\def\pkfile{{\tt .pk} file}
\def\plainTeX{plain \TeX}
\def\PlainTeX{Plain \TeX}
\def\pp{p\p}
\def\pt{\thinspace {\rm pt}}
\def\pxlfile{{\tt .pxl} file}
\def\tequiv{\unskip $\>\equiv\>$} % equivalence in text
\def\texbook{{\sl The \TeX book}\itcorr}
\let\tex@ = \TeX
\def\TeX{\tex@\null}
\def\TeXMeX{\TeX\ M\kern-.11em\lower .5ex\hbox{E}\kern-.125em X\null}%
\def\tfmfile{{\tt .tfm} file}
\def\thisbook{{\sl \TeX\ for the Impatient\/}}
\let\ths = \thinspace
\def\tminus{\unskip\allowbreak $\>-\>$\allowbreak} % minus in text
\def\tplus{\unskip\allowbreak $\>+\>$\allowbreak} % plus in text
\def\TUG{\TeX{} Users Group}
\def\Vcomma,{$V$\kern-2pt,}
\def\visiblespace{{\tentt \char'040}}
\def\Vperiod.{$V$\kern-2pt.}
\let\vs=\visiblespace
\def\xrefpg#1{page~\xrefn{#1}}
% \tighten attempts to shorten the number of lines occupied by a paragraph.
\def\tighten{\looseness=-1
\spaceskip = .9\fontdimen2\font plus \fontdimen3\font
minus 1.1\fontdimen4\font
}
% \itcorr can be used at the end of a macro that puts its argument in
% italics in order to produce an italic correction just when it's needed.
% It won't look inside a following macro call, however.
\def\itcorr{\futurelet\next\itcorrA}
\def\itcorrA{\ifx.\next\else\ifx,\next\else\/\fi\fi}
% Arrange N items in three columns.
% A right brace is needed at the end of the list to match the \bgroup.
%
\def\threecolumns{\nobreak\vskip\abovedisplayskip\dothreecolumns}
\def\dothreecolumns#1 {\bgroup
\parindent = 0pt
\makecolumns #1/3:
}
% We don't want to make < an active character because then it cannot be used
% in \ifnum tests. So, \<foo> denotes a nonterminal `foo'.
%
\def\<#1>{$\langle${\rm\it \kern-.2pt #1\kern.65pt}$\rangle$}
\let\beginit = \environment
\let\endit = \endenvironment
\def\eatpar#1\par{}
% \needspace breaks out the page if there's less than #1 left on it.
\def\needspace#1{%
\saveskip = \lastskip
\par % force vertical mode
\vfil
\penalty 1000
\vskip #1
\penalty9999
\par % exercise the page builder
\vskip -#1 plus -1fil
\vskip -\saveskip \vskip \saveskip % to restore \lastskip
}
% Expanded cross-referencing for various parts of the books.
%
% Sometimes it is clearer to refer to a cross-reference as a control
% sequence.
%
\def\ctsref{\begingroup \catcode`\@ = \letter \@ctsref}
\def\@ctsref#1{(\xref{#1})\endgroup}
\def\xrefdelim[#1]{page~\xrefn{#1}} % this form doesn't need braces
\def\xrefndelim[#1]{\xrefn{#1}} % this form doesn't need braces
% This command comes at the beginning of chapters, after the \chapter
% command and before the text. Hence the \par in the template
% and the \noindent
%
\def\chapterdef#1#2\par{%
\@writeaux{%
\string\gdef\expandafter\string
\csname#1_C\endcsname{\the\chapterno}}%
\noindent
}
\def\chapternum#1{%
\def\csn{#1_C}%
\expandafter\ifx\csname\csn\endcsname \relax
\expandafter\def\csname\csn\endcsname{`#1'}%
\ifxrefwarning
\message{Undefined chapter `#1'.}%
\fi
\fi
\csname\csn\endcsname
}
\def\chapterref#1{Section~\chapternum{#1}}
\def\headcit#1#2{``{\rm #1}'' (\xref{#2})}
\def\conceptcit#1{\headcit{#1}{#1}}
\def\seeconcept#1{(see ``{\rm #1}'', \xref{#1})}
% Special types of pictures.
%
% Glue pictures:
%
\newdimen\glueboxwidth
\newdimen\boxdepth \boxdepth = 3.5pc
\newskip\underlabel \underlabel= .1\boxdepth % space under `width n'.
\def\squeezeglue{\glueboxwidth = .725\glueboxwidth}
\def\labelledbox#1 #2 #3{\vtop{%
\hrule
\hbox{%
\vrule
\hbox to #1{\hfil \vbox to #2{\vfil#3\vskip\underlabel}\hfil}%
\vrule
}%
\hrule
}}%
% Make a picture of a box.
%
\def\picbox#1 {%
\glueboxwidth = #1pc \squeezeglue
\vtop{%
\hbox to \glueboxwidth{\strut \hfil {\it box}\hfil}%
\labelledbox % Have to have spaces after the arguments.
{\glueboxwidth}
{\boxdepth}
{\halign{\hfil##\hfil\cr width #1\cr}}%
}%
}
% And of glue.
%
\def\gluebox#1 #2 #3 #4 {\vtop{%
\glueboxwidth = #4pc \squeezeglue
\hbox to \glueboxwidth{\strut \hfil {\it glue}\hfil}%
\nointerlineskip
\kern2pt % to move the brace down a bit
\hbox{$\overbrace{\hbox{\hskip\glueboxwidth}}$}%
\kern-3pt % The \overbrace puts in 3pt below itself.
\nointerlineskip
\vbox to \boxdepth{%
\hsize = \glueboxwidth
\vskip 2pt
\advance\baselineskip by -2pt
\centerline{\strut size #1}%
\centerline{stretch #2}%
\centerline{shrink #3}%
\centerline{width #4}%
\vss
}%
\kern 1.5pt % I don't know why this is needed.
\nointerlineskip
\hbox{$\underbrace{\hbox{\hskip\glueboxwidth}}$}%
}}
\def\gluepicture#1 #2{{\ninerm
\medskip
\vtop{%
\setbox0 = \hbox{#2}% The glue and box pictures.
\glueboxwidth = \wd0
\leftline{\box0}%
\kern 6pt
\hbox to \glueboxwidth{\leftarrowfill{ width #1 }\rightarrowfill}%
}%
\medskip
}}
% Box pictures.
%
% Set up a `reference point' and the macro for a labelled height, for use
% in forming pictures of boxes.
%
\newbox\refpoint
\setbox\refpoint = \vbox to 0pt{%
\kern-2.6pt
\hbox to 0pt{\kern-2.2pt $\bullet$\hss}
\vss
}%
\def\labelledheight#1#2{%
\vtop to #1{\offinterlineskip
\setbox0=\hbox{#2}\skip0=\wd0
\hbox to \skip0{\hss\tenex\char"78\hss}\kern-4pt
{\cleaders\hbox to \skip0{\hss\tenex\char"3F\hss}\vfil}%
\vskip1pt\box0\vskip1pt
{\cleaders\hbox to \skip0{\hss\tenex\char"3F\hss}\vfil}%
\kern -6pt\boxmaxdepth 0pt\hbox to \skip0{\hss\tenex\char"79\hss}}}
% Paul's updates -- no longer needed; we have converged.
%
%\input paulmacs
% Read the cross-reference definitions.
%
\readauxfile
\catcode`\@ = \other % Make @ an `other' character again.
\catcode`\^ = \active % Make ^'s do indexing outside of math mode.