Eplain

This manual documents the Eplain macros, version 3.14, April 2024. Eplain provides functionality for plain TeX that is intended to be useful regardless of how your document is actually formatted.

Most of this manual is in the public domain, like most of the Eplain code. It was originally written by Karl Berry, starting in 1989. Steven Smith wrote the documentation for the commutative diagram macros; this chapter is under the GNU General Public License. Adam Lewenberg has made additions and corrections. Oleg Katsitadze wrote the section on LaTeX packages and the chapter on hyperlinks, and updates throughout.

The Eplain home page is https://tug.org/eplain.

Short Table of Contents

Table of Contents


1 Introduction

The Eplain macro package expands on and extends the definitions in plain TeX. Its home on the web is https://tug.org/eplain.

This manual describes the definitions that you, as either an author or a macro writer, might like to use. It doesn’t discuss the implementation; see comments in the source code (xeplain.tex) for that.

Eplain is not intended to provide typesetting capabilities, as does LaTeX (originally written by Leslie Lamport) and Texinfo (originally written by Richard Stallman). Instead, it provides definitions that are intended to be useful regardless of the high-level commands that you use when you actually prepare your manuscript.

For example, Eplain does not have a command \section to format section headings in an “appropriate” way, such as LaTeX’s \section. The philosophy of Eplain is that some people will always need or want to go beyond the macro designer’s idea of “appropriate”. Such canned macros are fine—as long as you are willing to accept the resulting output. If you don’t like the results, or if you are trying to match a different format, you have to put in extra work to override the defaults.

On the other hand, almost everyone would like capabilities such as cross-referencing by labels, so that you don’t have to put actual page numbers in the manuscript. The author of Eplain is not aware of any generally available macro packages that (1) do not force their typographic style on an author, and yet (2) provide such capabilities.

Besides such generic macros as cross-referencing, Eplain contains another set of definitions: ones that change the conventions of plain TeX’s output. For example, math displays in TeX are, by default, centered. If you want your displays to come out left-justified, you have to plow through The TeXbook to find some way to do it, and then adapt the code to your own needs. Eplain tries to take care of the messy details of such things, while still leaving the detailed appearance of the output up to you.

Finally, numerous definitions turned out to be useful as Eplain was developed. They are also documented in this manual, on the chance that people writing other macros will be able to use them.

You can send bug reports or suggestions to . The current version number of Eplain is defined as the macro \fmtversion at the end of the source file eplain.tex. When corresponding, please refer to it.

To subscribe to this mailing list (anyone can subscribe, and archives are public), visit https://lists.tug.org/tex-eplain.

David Walden reported his experience with Eplain as a new user. The article is available online at https://tug.org/pracjourn/2005-4/walden. An introductory article (written for TUGboat) is also available online at https://tug.org/eplain/misc/tb84katsi.pdf.

Finally, here are two alternatives to Eplain:

  1. If you just want to load the LaTeX color or graphics package, the LaTeX team’s miniltx.tex suffices:
    \input miniltx.tex
    \input graphicx.tex
    
  2. If you’re interested in a fully-fledged format that shares much of Eplain’s (and plain.tex’s) philosophy, check out OpTeX: https://ctan.org/pkg/optex.

2 Installation

Your TeX installation should already contain a version of Eplain (eplain.tex) in its main texmf tree; with TeX Live, it’s in .../texmf-dist/tex/eplain/eplain.tex.

Generally, you can just use that version and there is no need to do anything else. But if you want to use a newer version of Eplain for a given document, you can put the new eplain.tex in the document’s directory, and it will be found.

If you want to install a new eplain.tex in some other place, set an environment variable (commonly, TEXINPUTS) to tell TeX how to find it.

Distributions should also create and maintain the eplain.fmt file file. But if you want to do it yourself, you can:

$ touch eplain.aux
$ initex
This is TeX, ...
**&plain eplain
(eplain.tex)
*\dump
... messages ...

You must make sure that eplain.aux exists before you run initex; otherwise, warning messages about undefined labels will never be issued.

You then have to install the resulting eplain.fmt in your local texmf tree or set an environment variable (TEXFORMATS to tell TeX how to find it. You’ll need to consult your distribution’s documentation about that.


3 Invoking Eplain

The simplest way to use Eplain is simply to put:

\input eplain

at the beginning of your (plain TeX) input file. The macro file is small enough that reading it does not take long.

However, if a format (.fmt) file has been created for Eplain (see the previous section), you can eliminate even the time spent reading the macro source file. You do this by responding &eplain to TeX’s ‘**’ prompt. For example:

$ tex
This is TeX, ...
**&eplain myfile

In TeX Live and other distributions, a command-line executable named eplain is provided which reads the eplain.fmt file automatically.

If you write something which you will be distributing to others, you won’t know if the Eplain format will be loaded already. If it is, then doing \input eplain will waste time; if it isn’t, then you must load it. To solve this, Eplain defines the control sequence \eplain to be the letter t (a convention borrowed from Lisp; it doesn’t matter what the definition is, only that the definition exists). Therefore, you can do the following:

\ifx\eplain\undefined \input eplain \fi

where \undefined must never acquire a definition.

Eplain consists of several source files:

xeplain.tex

most of the macros;

arrow.tex

commutative diagram macros (see Arrow theoretic diagrams), written by Steven Smith;

btxmac.tex

bibliography-related macros (see Citations and bibliographies);

iftex.sty

sets the switch \ifpdf (among other things), which can be used to detect direct PDF output (see Checking for PDF output), originally written by Heiko Oberdiek;

path.sty

macro for allowing line breaks at punctuation characters within long pathnames, electronic mail addresses, etc., (see Paths), written by Philip Taylor;

texnames.sty

abbreviations for various TeX-related names (see Logos), edited by Nelson Beebe.

The file eplain.tex is all of these files merged together, with comments removed. The original sources can be found in Eplain source zip archive in your TeX distribution, on CTAN or on Eplain’s home page at https://tug.org/eplain.

All of these files except xeplain.tex can be input individually, if all you want are the definitions in that file.

Also, since the bibliography macros are fairly extensive, you might not want to load them, to conserve TeX’s memory. Therefore, if the control sequence \nobibtex is defined, then the bibliography definitions are skipped. You must set \nobibtex before eplain.tex is read, naturally. For example, you could start your input file like this:

\let\nobibtex = t
\input eplain

By default, \nobibtex is not defined, and so the bibliography definitions are made.

Likewise, define \noarrow if you don’t want to include the commutative diagram macros from arrow.tex, perhaps because you already have conflicting ones.

If you don’t want to read or write an aux file at all, for any kind of cross-referencing, define \noauxfile before reading eplain.tex. This also turns off all warnings about undefined labels.

Eplain conflicts with AMSTeX (to be precise, with amsppt.sty): the macros \cite and \ref are defined by both.

If you want to use AMSTeX’s \cite, the solution is to define \nobibtex before reading Eplain, as described above.

If you have amsppt.sty loaded and use \ref, Eplain writes a warning on your terminal. If you want to use the AMSTeX \ref, do \let\ref = \amsref after reading Eplain. To avoid the warning, do \let\ref = \eplainref after reading Eplain and before using \ref.

Sometimes you may need to run TeX more then once on your .tex file in order to produce and typeset indexes, resolve undefined cross-references and/or citations. The shell script texi2dvi from the Texinfo documentation system (see https://www.gnu.org/software/texinfo) can automate this process: it runs BibTeX, MakeIndex and TeX as many times as needed to complete the compilation process. You will need to set the LATEX environment variable to ‘tex’. For example, in a Bourne-compatible shell, the following command will do all the work:

$ LATEX=tex texi2dvi file.tex

Despite the name, texi2dvi can also produce .pdf output (among other formats); set LATEX=pdftex for this. See the output from texi2dvi --help for a full list of options.


4 User definitions

This chapter describes definitions that are meant to be used directly in a document. When appropriate, ways to change the default formatting are described in subsections.


4.1 Diagnostics

Plain TeX provides the \tracingall command, to turn on the maximum amount of tracing possible in TeX. The (usually voluminous) output from \tracingall goes both on the terminal and into the transcript file. It is sometimes easier to have the output go only to the transcript file, so you can peruse it at your leisure and not obscure other output to the terminal. So, Eplain provides the command \loggingall. (For some reason, this command is available in Metafont, but not in TeX.)

It is also sometimes useful to see the complete contents of boxes. \tracingboxes does this. (It doesn’t affect whether or not the contents are shown on the terminal.)

You can turn off all tracing with \tracingoff.

You can also turn logging on and off globally, so you don’t have to worry about whether or not you’re inside a group at the time of command. These variants are named \gloggingall and \gtracingall.

Finally, if you write your own help messages (see \newhelp in The TeXbook), you want a convenient way to break lines in them. This is what TeX’s \newlinechar parameter is for; however, plain TeX doesn’t set \newlinechar. Therefore, Eplain defines it to be the character ^^J.

For example, one of Eplain’s own error messages is defined as follows:

\newhelp\envhelp{Perhaps you forgot to end the previous^^J%
   environment? I'm finishing off the current group,^^J%
   hoping that will fix it.}%

4.2 Rules

The default dimensions of rules are defined in chapter 21 of the The TeXbook. To sum up what is given there, the “thickness” of rules is 0.4pt by default. Eplain defines three parameters that let you change this dimension: \hruledefaultheight, \hruledefaultdepth, and \vruledefaultwidth. By default, they are defined as The TeXbook describes.

But it would be wrong to redefine \hrule and \vrule. For one thing, some macros in plain TeX depend on the default dimensions being used; for another, rules are used quite heavily, and the performance impact of making it a macro can be noticeable. Therefore, to take advantage of the default rule parameters, you must use \ehrule and \evrule.


4.3 Citations and bibliographies

Bibliographies are part of almost every technical document. To handle them conveniently, you need two things: a program to do the tedious formatting, and a way to cite references by labels, rather than by numbers. The BibTeX program, written by Oren Patashnik, takes care of the first item; the citation commands in LaTeX, written to be used with BibTeX, take care of the second. Therefore, Eplain adopts the use of BibTeX, and virtually the same interface as LaTeX.

The general idea is that you put citation commands in the text of your document, and commands saying where the bibliography data is. When you run TeX, these commands produce output on the file with the same root name as your document (by default) and the extension .aux. BibTeX reads this file. You should put the bibliography data in a file or files with the extension .bib. BibTeX writes out a file with the same root name as your document and extension .bbl. Eplain reads this file the next time you run your document through TeX. (It takes multiple passes to get everything straight, because usually after seeing your bibliography typeset, you want to make changes in the .bib file, which means you have to run BibTeX again, which means you have to run TeX again…) An annotated example of the whole process is given below.

If your document has more than one bibliography—for example, if it is a collection of papers—you can tell Eplain to use a different root name for the .bbl file by defining the control sequence \bblfilebasename. The default definition is simply \jobname.

On the other hand, if your document’s bibliography is very simple, you may prefer to create the .bbl file yourself, by hand, instead of using BibTeX. An annotated example of this approach is also given below.

See the document BibTeXing (whose text is in the file btxdoc.tex, which should be in the Eplain distribution you got) for information on how to write your .bib files. Both the BibTeX and the Eplain distributions contain several examples, also.

The \cite command produces a citation in the text of your document. The exact printed form the citation will take is under your control (see Formatting citations). \cite takes one required argument, a comma-separated list of cross-reference labels (see Cross-references, for exactly what characters are allowed in such labels). Warning: spaces in this list are taken as part of the following label name, which is probably not what you expect. The \cite command also produces a command in the .aux file that tells BibTeX to retrieve the given reference(s) from the .bib file. \cite also takes one optional argument, which you specify within square brackets, as in LaTeX. This text is simply typeset after the citations. (See the example below.)

Eplain can create hypertext links for citations pointing to the relevant bibliography entries (see Citation hyperlinks: cite, bib).

Another command, \nocite, puts the given reference(s) into the bibliography, but produces nothing in the text.

The \bibliography command is next. It serves two purposes: producing the typeset bibliography, and telling BibTeX the root names of the .bib files. Therefore, the argument to \bibliography is a comma separated list of the .bib files (without the ‘.bib’). Again, spaces in this list are significant.

You tell BibTeX the particular style in which you want your bibliography typeset with one more command: \bibliographystyle. The argument to this is a single filename style, which tells BibTeX to look for a file style.bst.

Numerous styles have been defined by now; see https://www.ctan.org/topic/bibtex-sty. One particular case: the apalike semi-standard style requires \input apalike.tex to function properly (else text is overwritten); other APA-like (“humanities”) styles surely also require this or similar changes.

See the document Designing BibTeX styles (whose text is in the btxhak.tex) for information on how to write your own styles.

Eplain automatically reads the citations from the .aux file when your job starts.

If you don’t want to see the messages about undefined citations, you can say \xrefwarningfalse before making any citations. Eplain automatically does this if the .aux file does not exist. You can restore the default by saying \xrefwarningtrue.

Here is a TeX input file that illustrates the various commands.

\input eplain                    % Reads the .aux file.
Two citations to Knuthian works:
  \cite[note]{surreal,concrete-math}.
\beginsection{References.}\par   % Title for the bibliography.
\bibliography{knuth}             % Use knuth.bib for the labels.
\bibliographystyle{plain}        % Number the references.
\end                             % End of the document.

If we suppose that this file was named citex.tex and that the bibliography data is in knuth.bib (as the above \bibliography command says), the following commands do what’s required. (‘$ ’ represents the shell prompt.)

$ tex citex     (produces undefined citation messages)
$ bibtex citex  (read knuth.bib and citex.aux, write citex.bbl)
$ tex citex     (read citex.bbl, still have undefined citations)
$ tex citex     (one more time, to resolve the references)

The texi2dvi program can help you automate this process (see Invoking Eplain).

For simple documents you might choose to write the .bbl file yourself, instead of running BibTeX. For this scenario, the following commands should suffice:

$ tex citex     (read citex.bbl, produces undefined citation messages)
$ tex citex     (one more time, to resolve the references)

The output looks something like (because we used the plain bibliography style):

Two citations to Knuthian works: [2,1 note].

References

[1] Ronald L. Graham, Donald E. Knuth, and Oren Patashnik. Concrete Mathematics. Addison-Wesley, Reading, Massachusetts, 1989.

[2] Donald E. Knuth. Surreal Numbers. Addison-Wesley, Reading, Massachusetts, 1974.

See the BibTeX documentation for information on how to write the bibliography databases, and the bibliography styles that are available. (If you want your references printed with names, as in [Knu74], instead of numbered, the bibliography style is alpha.)


4.3.1 Formatting citations

You may wish to change Eplain’s formatting of citations; i.e., the result of your \cite commands. By default, the citation labels are printed one after another, separated by commas and enclosed in brackets, using the main text font. Some formats require other styles, such as superscripted labels. You can accommodate such formats by redefining the following macros.

\printcitestart
\printcitefinish

Eplain expands these macros at the beginning and end of the list of citations for each \cite command. By default, they produce a ‘[’ and ‘]’, respectively.

\printbetweencitations

If a \cite command has multiple citations, as in \cite{acp,texbook}, Eplain expands this macro in between each pair of citations. By default, it produces a comma followed by a space.

\printcitenote

This macro takes one argument, which is the optional note to the \cite command. If the \cite command had no note, this macro isn’t used. Otherwise, it should print the note. By default, the note is preceded with a comma and a space.

Here is an example, showing you could produce citations as superscripted labels, with the optional notes in parentheses.

\def\printcitestart{\unskip $^\bgroup}
\def\printbetweencitations{,}
\def\printcitefinish{\egroup$}
\def\printcitenote#1{\hbox{\sevenrm\space (#1)}}

4.3.2 Formatting bibliographies

You may wish to change Eplain’s formatting of the bibliography, especially with respect to the fonts that are used. Therefore, Eplain provides the following control sequences:

\biblabelwidth

This control sequence represents a \dimen register, and its value is the width of the widest label in the bibliography. Although it is unlikely you will ever want to redefine it, you might want to use it if you redefine \biblabelprint, below.

\biblabelprint

This macro takes one argument, the label to print. By default, the label is put in a box of width \biblabelwidth, and is followed by an enspace. When you want to change the spacing around the labels, this is the right macro to redefine.

\biblabelcontents

This macro also takes one argument, the label to print. By default, the label is printed using the font \bblrm (below), and enclosed in brackets. When you want to change the appearance of the label, but not the spacing around it, this is the right macro to redefine.

\biblabelprecontents
\biblabelpostcontents

Macros expanded before and after \biblabelcontents, respectively. For example, to get left-justified numeric labels (they are right-justified by default):

\def\biblabelprecontents{\relax}
\def\biblabelpostcontents{\hss}
\bblrm

The default font used for printing the bibliography.

\bblem

The font used for printing the titles and other “emphasized” material.

\bblemph

Typesets its argument using \bblem, then inserts an italic correction.

\bblsc

In some styles, authors’ names are printed in a caps-and-small-caps font. In those cases, this font is used.

\bblnewblock

This is invoked between each of the parts of a bibliography entry. The default is to leave some extra space between the parts; you could redefine it to start each part on a new line (for example). A part is simply a main element of the entry; for example, the author is a part. (It was LaTeX that introduced the (misleading, as far as I am concerned) term ‘block’ for this.)

\biblabelextraspace

Bibliography entries are typeset with a hanging indentation of \biblabelwidth plus this. The default is .5em, where the em width is taken from the \bblrm font. If you want to change this, you should do it inside \bblhook.

\bblhook

This is expanded before reading the .bbl file. By default, it does nothing. You could, for example, define it to set the bibliography fonts, or produce the heading for the references. Two spacing parameters must be changed inside \bblhook: \parskip, which produces extra space between the items; and \biblabelextraspace, which is described above. (By the way, \hookappend won’t work with \bblhook, despite the names. Just use \def.)

If you are desperate, of course you can also hand-edit the .bbl file that BibTeX produces to do anything you wish.


4.3.3 Commands from LaTeX

Because of the historical connection between BibTeX and LaTeX, in practice many bibliography styles and bibliographies use LaTeX commmands that are not part of bibliography handling, per se.

To support this, btxmac.tex (and thus Eplain) define the following. In all cases, an existing definition (e.g., from miniltx.tex, see Loading LaTeX packages) will not be overwritten. Here is the list:

\newcommand
\renewcommand
\providecommand

Defining new commands in various ways. The Eplain versions do not support the *-form of these; use miniltx for that.

\em
\emph
\sc
\textbf

Selecting fonts.

\mbox

A horizontal box.

\newblock

Starts elements of a bibliography entry.

For full information about these, see the LaTeX manual and sources.


4.4 Displays

By default, TeX centers displayed material. (Displayed material is just whatever you put between $$’s—it’s not necessarily mathematics.) Many layouts would be better served if the displayed material was left-justified. Therefore, Eplain provides the command \leftdisplays, which indents displayed material by \parindent plus \leftskip, plus \leftdisplayindent.

You can go back to centering displays with \centereddisplays. (It is usually poor typography to have both centered and left-justified displays in a single publication, though.)

\leftdisplays also changes the plain TeX commands that deal with alignments inside math displays, \displaylines, \eqalignno, and \leqalignno, to produce left-justified text. You can still override this formatting by inserting \hfill glue, as explained in The TeXbook.

Eplain defines \eqnum and \eqalignnum which can be set up to produce either left-aligned or right-aligned equation numbers. \lefteqnumbers (\righteqnumbers) will define \eqnum to expand to \eqno (\leqno), and \eqalignnum to expand to \eqalignno (\leqalignno). Default is \righteqnumbers (right-aligned equation numbers).


4.4.1 Formatting displays

If you want some other kind of formatting, you can write a definition of your own, analogous to \leftdisplays. You need only make sure that \leftdisplaysetup is called at the beginning of every display (presumably by invoking it in TeX’s \everydisplay parameter).

\leftdisplays expands the old value of \everydisplay before calling \leftdisplaysetup, so that any changes you have made to it won’t be lost. That old token list as available as the value of the token register \previouseverydisplay.


4.5 Time of day

TeX provides the day, month, and year as numeric quantities (unless your TeX implementation is woefully deficient). Eplain provides some control sequences to make them a little more friendly to humans.

\monthname produces the name of the current month, abbreviated to three letters.

\fullmonthname produces the name of the current month, unabbreviated (in English).

\timestring produces the current time, as in ‘1:14 p.m.’

\timestamp produces the current date and time, as in ‘23 Apr 64 1:14 p.m.’. (Except the spacing is slightly different.)

\today produces the current date, as in ‘23 April 1964’.


4.6 Lists

Many documents require lists of items, either numbered or simply enumerated. Plain TeX defines one macro to help with creating lists, \item, but that is insufficient in many cases. Therefore, Eplain provides two pairs of commands:

\numberedlist … \endnumberedlist
\orderedlist … \endorderedlist

These commands (they are synonyms) produce a list with the items numbered sequentially, starting from one. A nested \numberedlist labels the items with lowercase letters, starting with ‘a’. Another nested \numberedlist labels the items with roman numerals. Yet more deeply nested numbered lists label items with ‘*’.

\unorderedlist … \endunorderedlist

This produces a list with the items labelled with small black boxes (“square bullets”). A nested \unorderedlist labels items with em-dashes. Doubly (and deeper) nested unordered lists label items with ‘*’s.

The two kinds of lists can be nested within each other, as well.

In both kinds of lists, you begin an item with \li. An item may continue for several paragraphs. Each item starts a paragraph.

You can give \li an optional argument, a cross-reference label. It’s defined to be the “marker” for the current item. This is useful if the list items are numbered. You can produce the value of the label with \xrefn. See Cross-references.

Eplain can create hypertext links for the markers produced by \xrefn pointing to the relevant list item (see List hyperlinks: li).

You can also say \listcompact right after \numberedlist or \unorderedlist. The items in the list will then not have any extra space between them (see Formatting lists). You might want to do this if the items in this particular list are short.

Here is an example:

\numberedlist\listcompact
\li The first item.
\li The second item.

The second paragraph of the second item.
\endnumberedlist

4.6.1 Formatting lists

Several registers define the spacing associated with lists. It is likely that their default values won’t suit your particular layout.

\abovelistskipamount, \belowlistskipamount

The vertical glue inserted before and after every list, respectively.

\interitemskipamount

The vertical glue inserted before each item except the first. \listcompact resets this to zero, as mentioned above.

\listleftindent, \listrightindent

\listrightindent is the amount of space by which the list is indented on the right; i.e., it is added to \rightskip. \listleftindent is the amount of space, relative to \parindent, by which the list is indented on the left. Why treat the two parameters differently? Because (a) it is more useful to make the list indentation depend on the paragraph indentation; (b) footnotes aren’t formatted right if \parindent is reset to zero.

The three vertical glues are inserted by macros, and preceded by penalties: \abovelistskip does \vpenalty\abovelistpenalty and then \vskip\abovelistskip. \belowlistskip and \interitemskip are analogous.

In addition, the macro \listmarkerspace is called to separate the item label from the item text. This is set to \enspace by default.

If you want to change the labels on the items, you can redefine these macros: \numberedmarker or \unorderedmarker. The following registers might be useful if you do:

\numberedlistdepth, \unorderedlistdepth

These keep track of the depth of nesting of the two kinds of lists.

\itemnumber, \itemletter

These keep track of the number of items that have been seen in the current numbered list. They are both integer registers. The difference is that \itemnumber starts at one, and \itemletter starts at 97, i.e., lowercase ‘a’.

You can also redefine the control sequences that are used internally, if you want to do something radically different: \beginlist is invoked to begin both kinds of lists; \printitem is invoked to print the label (and space following the label) for each item; and \endlist is invoked to end both kinds of lists.


4.7 Verbatim listing

It is sometimes useful to include a file verbatim in your document; for example, part of a computer program. The \listing command is given one argument, a filename, and produces the contents of that file in your document. \listing expands \listingfont to set the current font. The default value of \listingfont is \tt.

You can take arbitrary actions before reading the file by defining the macro \setuplistinghook. This is expanded just before the file is input.

If you want to have line numbers on the output, you can say \let\setuplistinghook = \linenumberedlisting. The line numbers are stored in the count register \lineno while the file is being read. You can redefine the macro \printlistinglineno to change how they are printed.

Normally, the \listing command will add a final empty line at the end of the output, even if the file does not end in a newline. To suppress this final line, you can say \let\setuplistinghook = \nolastlinelisting. This also works with line numbers (say \def\setuplistinghook{\linenumberedlisting \nolastlinelisting}), but only if \printlistinglineno consists exclusively of boxes at the top level (i.e., any \kerns or glue should be wrapped up in a box).

You can use the form feed control character (ASCII code 12, typed as CTRL-L) in the file to force a page break in the output.

You can produce in-line verbatim text in your document with \verbatim. End the text with |endverbatim. If you need a ‘|’ in the text, double it. If the first character of the verbatim text is a space, use | . (| will work elsewhere in the argument, too, but isn’t necessary.)

For example:

\verbatim| ||\#%&!|endverbatim

produces |\#%&!.

Line breaks and spaces in the verbatim text are preserved.

You can change the verbatim escape character from the default ‘|’ with \verbatimescapechar char; for example, this changes it to ‘@’.

\verbatimescapechar \@

The backslash is not necessary in some cases, but is in others, depending on the catcode of the character. The argument to \verbatimescapechar is used as \catcode `char, so the exact rules follow that for \catcode.

To reset the category code of all special characters to 12 (“other”), \verbatim uses \uncatcodespecials (see Category codes). If you make additional characters “special”, you should extend \dospecials to include those characters, lest they be given special treatment inside verbatim environments. For example,

\catcode`\A=\active
% Try commenting out the following line.
\expandafter\def\expandafter\dospecials\expandafter{\dospecials\do\A}
\verbatimA#$%_^|endverbatim

Because \verbatim must change the category code of special characters, calling inside a macro definition of your own does not work properly. For example:

\def\mymacro{\verbatim &#%|endverbatim}% Doesn't work!

To accomplish this, you must change the category codes yourself before making the macro definition. Perhaps \uncatcodespecials will help you (see Category codes).


4.8 Contents

Producing a table of contents that is both useful and aesthetic is one of the most difficult design problems in any work. Naturally, Eplain does not pretend to solve the design problem. Collecting the raw data for a table of contents, however, is much the same across documents. Eplain uses an auxiliary file with extension .toc (and the same root name as your document) to save the information.


4.8.1 Writing the .toc file

To write an entry for the table of contents, you say \writetocentry{part}{text}, where part is the type of part this entry is, e.g., ‘chapter’, and text is the text of the title. \writetocentry puts an entry into the .toc file that looks like \tocpartentry{text}{page number} (unless part is an integer, see below). The text is written unexpanded.

A related command, \writenumberedtocentry, takes one additional argument, the first token of which is expanded at the point of the \writenumberedtocentry, but the rest of the argument is not expanded. The usual application is when the parts of the document are numbered. On the other hand, the one-level expansion allows you to use the argument for other things as well (author’s names in a proceedings, say), and not have accents or other control sequences expanded. The downside is that if you want full expansion of the third argument, you don’t get it—you must expand it yourself, before you call \writenumberedtocentry.

For example:

\writenumberedtocentry{chapter}{A $\sin$ wave}{\the\chapno}
\writetocentry{section}{A section title}

Supposing \the\chapno expanded to ‘3’ and that the \write’s occurred on pages eight and nine, respectively, the above writes the following to the .toc file:

\tocchapterentry{A $\sin$ wave}{3}{8}
\tocsectionentry{A section title}{9}

A variation on \writenumberedtocentry is \writenumberedtocline, differing only in the order of the parameters it takes and writes for the \tocpartentry control sequences. To continue the previous example:

\writenumberedtocline{chapter}{\the\chapno}{A $\sin$ wave}

writes the following to the .toc file:

\tocchapterentry{3}{A $\sin$ wave}{8}

Such ordering of the parameters allows the \tocpartentry macros to typeset the text of the entry without actually reading it as an argument. This is required for entries which need to change character catcodes, e.g., to produce verbatim text (see Verbatim listing).

Each of \writetocentry, \writenumberedtocentry and \writenumberedtocline processes a numeric part argument specially. If you pass part expanding to an integer, these macros write into the .toc file an entry that starts with \tocentry{part}. Thus, you can define a single \tocentry macro which formats all entries for a table of contents. To continue the previous examples:

\writenumberedtocentry{1}{A $\sin$ wave}{\the\chapno}
\writenumberedtocline{1}{\the\chapno}{A $\sin$ wave}
\writetocentry{2}{A section title}

writes the following to the .toc file:

\tocentry{1}{A $\sin$ wave}{3}{8}
\tocentry{1}{3}{A $\sin$ wave}{8}
\tocentry{2}{A section title}{9}

4.8.2 Reading the .toc file

You read the .toc file with the command \readtocfile. Naturally, whatever \toc… entry commands that were written to the file must be defined when \readtocfile is invoked. Eplain has minimal definitions for \tocchapterentry, \tocsectionentry, and \tocsubsectionentry, just to prevent undefined control sequence errors in common cases. They aren’t suitable for anything but preliminary proofs.

Each of \writetocentry, \writenumberedtocentry and \writenumberedtocline opens the .toc file for writing, thereby deleting the information from the previous run. You should therefore arrange that \readtocfile be called before the first call to a \writetoc… macro, or after the last call. You can’t arbitrarily mix reading and writing.

\readtocfile does not itself delete the information from the .toc file, so that you can call it several times, e.g., to create both a short and normal table of contents. (To produce this particular case, define \tocsectionentry to produce nothing while you are reading .toc file for a short table of contents (see Macro arguments).)

On the other hand, if you don’t want to rewrite the .toc file at all, perhaps because you are only running TeX on part of your manuscript, you can set \rewritetocfilefalse.


4.8.3 Changing the .toc file’s root name

By default, the .toc file has the root \jobname. If your document has more than one contents—for example, if it is a collection of papers, some of which have their own contents—you can tell Eplain to use a different root name by defining the control sequence \tocfilebasename.

Note that \writetocentry, \writenumberedtocentry and \writenumberedtocline will open the contents file for writing only at the first call, using the value of \tocfilebasename at that time. Changing the value of \tocfilebasename afterwards will not affect which file gets written, although it will affect which file gets read by \readcontentsfile. In case you need to write several contents files from a single TeX job, use \definecontentsfile (see Alternative contents files).


4.8.4 Alternative contents files

In addition to the usual table of contents, you may want to have a list of figures, list of tables, or other such contents-like list. You can do this with \definecontentsfile{abbrev}. All of the above commands are actually a special case that Eplain predefines with

\definecontentsfile{toc}

The abbrev is used both for the file extension and in the control sequence names.


4.9 Cross-references

It is often useful to refer the reader to other parts of your document; but putting literal page, section, equation, or whatever numbers in the text is certainly a bad thing.

Eplain therefore provides commands for symbolic cross-references. It uses an auxiliary file with extension .aux (and the same root name as your document) to keep track of the information. Therefore, it takes two passes to get the cross-references right—one to write them out, and one to read them in. Eplain automatically reads the .aux file at the first reference; after reading it, Eplain reopens it for writing.

You can control whether or not Eplain warns you about undefined labels. See Citations and bibliographies.

Labels in Eplain’s cross-reference commands can use characters of category code eleven (letter), twelve (other), ten (space), three (math shift), four (alignment tab), seven (superscript), or eight (subscript). For example, ‘(a1 $&^_’ is a valid label (assuming the category codes of plain TeX), but ‘%#\{’ has no valid characters.

You can also do symbolic cross-references for bibliographic citations and list items. See Citations and bibliographies, and Lists.

Eplain can create hypertext links for the cross-references (see Cross-reference hyperlinks: definexref, ref).


4.9.1 Defining generic references

Eplain provides the command \definexref for general cross-references. It takes three arguments: the name of the label (see section above for valid label names), the value of the label (which can be anything), and the “class” of the reference—whether it’s a section, or theorem, or what. For example:

\definexref{sec-intro}{3.1}{section}

Of course, the label value is usually generated by another macro using TeX count registers or some such.

\definexref doesn’t actually define label; instead, it writes out the definition to the .aux file, where Eplain will read it on the next TeX run.

The class argument is used by the \ref and \refs commands. See the next section.


4.9.2 Using generic references

To retrieve the value of the label defined via \definexref (see the previous section), Eplain provides the following macros:

\refn{label}
\xrefn{label}

\refn and \xrefn (they are synonyms) produce the bare definition of label. If label isn’t defined, issue a warning, and produce label itself instead, in typewriter. (The warning isn’t given if \xrefwarningfalse.)

\ref{label}

Given the class c for label (see the description of \definexref in the previous section), expand the control sequence \c word (if it’s defined) followed by a tie. Then call \refn on label. (Example below.)

\refs{label}

Like \ref, but append the letter ‘s’ to the \…word.

The purpose of the \…word macro is to produce the word ‘Section’ or ‘Figure’ or whatever that usually precedes the actual reference number.

Here is an example:

\def\sectionword{Section}
\definexref{sec-intro}{3.1}{section}
\definexref{sec-next}{3.2}{section}
See \refs{sec-intro} and \refn{sec-next} ...

This produces ‘See Sections 3.1 and 3.2 …’


4.10 Page references

Eplain provides two commands for handling references to page numbers, one for definition and one for use.

\xrdef{label}

Define label to be the current page number. This produces no printed output, and ignores following spaces.

\xref{label}

Produce the text ‘p. pageno’, which is the usual form for cross-references. The pageno is actually label’s definition; if label isn’t defined, the text of the label itself is printed. The ‘p. ’ prefix is defined by \xrefpageword. Its default definition is p.\thinspace.

Eplain can create hypertext links for the page references (see Page reference hyperlinks: xrdef, xref).


4.11 Equation references

Instead of referring to pages, it’s most useful if equation labels refer to equation numbers. Therefore, Eplain reserves a \count register, \eqnumber, for the current equation number, and increments it at each numbered equation.

Here are the commands to define equation labels and then refer to them:

\eqdef{label}

This defines label to be the current value of \eqnumber, and, if the current context is not inner, then produces a \eqnum command (see Displays). (The condition makes it possible to use \eqdef in an \eqalignno construction, for example.) The text of the equation number is produced using \eqprint. See Formatting equation references.

If label is empty, you still get an equation number (although naturally you can’t reliably refer to it). This is useful if you want to put numbers on all equations in your document, and you don’t want to think up unique labels.

To refer to the last equation with the empty label, you use the empty label in one of the equation reference macros (see below). This can be handy when you want to refer to an equation shortly after its definition, say, in the sentence following the displayed equation, and do not intend to refer to the equation later. But use this trick with extreme caution: if later you change the text and insert another empty definition between the original definition and the reference, the reference will start to refer to the new empty-labeled equation.

\eqdefn{label}

This is like \eqdef, except it always omits the \eqnum command. It can therefore be used in places where \eqdef can’t; for example, in a non-displayed equation. The text of the equation number is not produced, so you can also use it in the (admittedly unusual) circumstance when you want to define an equation label but not print that label.

\eqref{label}

This produces a formatted reference to label. If label is undefined (perhaps because it is a forward reference), it just produces the text of the label itself. Otherwise, it calls \eqprint.

\eqrefn{label}

This produces the cross-reference text for label. That is, it is like \eqref, except it doesn’t call \eqprint.

Equation labels can contain the same characters that are valid in general cross-references.

Eplain can create hypertext links for the equation references (see Equation reference hyperlinks: eq).


4.11.1 Formatting equation references

Both defining an equation label and referring to it should usually produce output. This output is produced with the \eqprint macro, which takes one argument, the equation number being defined or referred to. By default, this just produces ‘(number)’, where number is the equation number. To produce the equation number in a different font, or with different surrounding symbols, or whatever, you can redefine \eqprint. For example, the following definition would print all equation numbers in italics. (The extra braces define a group, to keep the font change from affecting surrounding text.)

\def\eqprint#1{{\it (#1)}}

In addition to changing the formatting of equation numbers, you might want to add more structure to the equation number; for example, you might want to include the chapter number, to get equation numbers like ‘(1.2)’. To achieve this, you redefine \eqconstruct. For example:

\def\eqconstruct#1{\the\chapternumber.#1}

(If you are keeping the chapter number in a count register named \chapternumber, naturally.)

The reason for having both \eqconstruct and \eqprint may not be immediately apparent. The difference is that \eqconstruct affects the text that cross-reference label is defined to be, while \eqprint affects only what is typeset on the page. The example just below might help.

Usually, you want equation labels to refer to equation numbers. But sometimes you might want a more complicated text. For example, you might have an equation ‘(1)’, and then have a variation several pages later which you want to refer to as ‘(1*)’.

Therefore, Eplain allows you to give an optional argument (i.e., arbitrary text in square brackets) before the cross-reference label to \eqdef. Then, when you refer to the equation, that text is produced. Here’s how to get the example just mentioned:

$$...\eqdef{a-eq}$$
...
$$...\eqdef[\eqrefn{a-eq}*]{a-eq-var}$$
In \eqref{a-eq-var}, we expand on \eqref{a-eq}, ...

We use \eqrefn in the cross-reference text, not \eqref, so that \eqprint is called only once.

As another example, consider the following requirement: we want to include chapter number in all equation references, and additionally we want to include the part number when referencing an equation from any part other than the one where the equation appears. For example, references to the third equation in chapter 2 of part 1 should be typeset as ‘(2.3)’ throughout part 1, but as ‘(I.2.3)’ in any other part. Let’s assume we have the current chapter and part numbers in count registers \chapnum and \partnum, respectively.

The idea is to have \eqconstruct store the part number of the equation (that is, the part number at the time of definition), so that later \eqprint can compare the stored number with the current part number (that is, the part number at the time of reference). The complicating factor is that internally, the result of \eqconstruct is both expanded and written out to the .aux file, and used to typeset the equation number, so the commands that store the part number should behave correctly in both situations. This is difficult to achieve with expandable commands; therefore, to avoid expansion problems, we are going to use only TeX primitives, which are non-expandable:

\newcount\eqpartnum

\def\eqconstruct#1{%
  \global\eqpartnum=\the\partnum\relax
  \number\chapnum.#1%
}

\def\eqprint#1{%
  \setbox0=\hbox{#1}%
  (\ifnum\partnum=\eqpartnum \else
     \uppercase\expandafter{\romannumeral\eqpartnum}.%
   \fi
   \box0)%
}%

In \eqconstruct, besides constructing the base equation number (e.g., ‘1.2’), we also store the part number of the equation in the count register \eqpartnum (\the\partnum is expanded when the equation number is written to the .aux file, so the equation label definition in the .aux file will contain the actual part number). In \eqprint, we need to know the equation’s part number before we typeset the base equation number, therefore we first put the argument in a box, thus causing \eqpartnum to be set.


4.11.2 Subequation references

Eplain also provides for one level of substructure for equations. That is, you might want to define a related group of equations with numbers like ‘2.1’ and ‘2.2’, and then be able to refer to the group as a whole: “… in the system of equations (2)…”.

The commands to do this are \eqsubdef and \eqsubdefn. They take one label argument like their counterparts above, and generally behave in the same way. The difference is in how they construct the equation number: instead of using just \eqnumber, they also use another counter, \subeqnumber. This counter is advanced by one at every \eqsubdef or \eqsubdefn, and reset to zero at every \eqdef or \eqdefn.

You use \eqref to refer to subequations as well as main equations.

To put the two together to construct the text that the label will produce, they use a macro \eqsubreftext. This macros takes two arguments, the “main” equation number (which, because the equation label can be defined as arbitrary text, as described in the previous section, might be anything at all) and the “sub” equation number (which is always just a number). Eplain’s default definition just puts a period between them:

\def\eqsubreftext#1#2{#1.#2}%

You can redefine \eqsubreftext to print however you like. For example, this definition makes the labels print as ‘2a’, ‘2b’, and so on.

\newcount\subref
\def\eqsubreftext#1#2{%
  \subref = #2           % The space stops a <number>.
  \advance\subref by 96  % `a' is character code 97.
  #1\char\subref
}

We must define a new count register, \subref, instead of using the scratch count register \count255, because ‘#1’ might include other macro calls which use \count255.


4.12 Indexing

Eplain provides support for generating raw material for an index, and for typesetting a sorted index. A separate program must do the actual collection and sorting of terms, because TeX itself has no support for sorting.

Eplain can create hypertext links pointing from the index to the index terms (see Index hyperlinks: idx).

Eplain’s indexing commands were designed to work with the program MakeIndex (https://ctan.org/pkg/makeindex); MakeIndex is also commonly included in prepackaged TeX distributions. It is beyond the scope of this manual to explain how to run MakeIndex, and all of its many options.

The basic strategy for indexing works like this:

  1. For a document foo.tex, Eplain’s indexing commands (e.g., \idx; see the section ‘Indexing terms’ below) write the raw index material to foo.idx.
  2. MakeIndex reads foo.idx, collects and sorts the index, and writes the result to foo.ind.
  3. Eplain reads and typesets foo.ind on a subsequent run of TeX. See the section ‘Typesetting an index’ below.

The texi2dvi program can help you automate this process (see Invoking Eplain).

If your document needs more than one index, each must have its own file. Therefore, Eplain provides the command \defineindex, which takes an argument that is a single letter, which replaces ‘i’ in the filenames and in the indexing command names described below. For example,

\defineindex{m}

defines the command \mdx to write to the file foo.mdx. Eplain simply does \defineindex{i} to define the default commands.

Note that MakeIndex does not use the above naming scheme for multiple indexes. Unless instructed otherwise, MakeIndex always writes its output to a file with extension .ind. For example, if you define an additional index with the command \defineindex{j}, you’ll need to run MakeIndex like this:

$ makeindex book.jdx -o book.jnd

For each index defined with \defineindex{n}, Eplain provides a switch \ifndx which controls whether indexing commands write index entries to the corresponding index file. However, even when index term writing is disabled, indexing commands still do all other processing of their arguments, including typesetting of proof index terms (see Proofing index terms.

For example, if you write \idxfalse near the beginning of a document foo.tex (before the first indexing command), Eplain will not open the default index file (foo.idx) and the corresponding indexing commands (\idx, \sidx, etc.) will not write index entries there. This may be useful for draft compilations of a manuscript, e.g., to avoid the overhead of index file input/output.


4.12.1 Indexing terms

Indexing commands in Eplain come in pairs: one command that only writes the index entry to the ‘.idx’ file (see above section), and one that also typesets the term being indexed. The former always starts with ‘s’ (for “silent”). In either case, the name always includes ‘Idx’, where I is the index letter, also described above. Eplain defines the index ‘i’ itself, so that’s what we’ll use in the names below.

The silent form of the commands take a subterm as a trailing optional argument. For example, \sidx{truth}[definition of] on page 75 makes an index entry that will eventually be typeset (by default) as

truth
  definition of, 75

Also, the silent commands ignore trailing spaces. The non-silent ones do not.


4.12.1.1 Indexing commands

Here are the commands.

  • \sidx{term}[subterm] makes an index entry for term, optionally with subterm subterm. \idx{term} also produces term as output. Example:
    \sidx{truth}[beauty of]
    The beauty of truth is \idx{death}.
    

    Subterms at the second and further levels can also be specified in subterm, using the \idxsubentryseparator character to separate them. This character is by default ‘!’.

  • \sidxname{First M.}{von Last}[subterm] makes an index entry for ‘von Last, First M.’. You can change the ‘, ’ by redefining \idxnameseparator. \idxname{First M.}{von Last} also produces First M. von Last as output. (These commands are useful special cases of \idx and \sidx.) Example:
    \sidxname{Richard}{Stark}
    \idxname{Donald}{Westlake} has written many kinds of novels, under
    almost as many names.
    
  • \sidxmarked\cs{term}[subterm] makes an index entry for term[subterm], but term will be put in the index as \cs{term}, but still sorted as just term. \idxmarked\cs{term} also typesets \cs{term}. This provides for the usual ways of changing the typesetting of index entries. Example:
    \def\article#1{``#1''}
    \sidxmarked\article{Miss Elsa and Aunt Sophie}
    Peter Drucker's \idxmarked\article{The Polanyis} is a remarkable 
    essay about a remarkable family.
    
  • \sidxsubmarked{term}\cs{subterm} makes an index entry for term, subterm as usual, but also puts subterm in the index as \cs{term}. \idxsubmarked{term}\cs{subterm} also typesets term \cs{subterm}, in the unlikely event that your syntax is convoluted enough to make this useful. Example:
    \def\title#1{{\sl #1}}
    \sidxsubmarked{Anderson, Laurie}\title{Strange Angels}
    The \idxsubmarked{Anderson}\title{Carmen} is a strange twist.
    

The commands above rely on MakeIndex’s feature for separating sorting of an index entry’s from its typesetting. You can use this directly by specifying an index entry as sort@typeset. For example:

\sidx{Ap-weight@$A_\pi$-weight}

will sort as Ap-weight, but print with the proper math. The @ here is MakeIndex’s default character for this purpose. To make an index entry with an @ in it, you have to escape it with a backslash; Eplain provides no macros for doing this.

After any index command, Eplain runs \hookaction{afterindexterm}. Because the index commands always add a whatsit item to the current list, you may wish to preserve a penalty or space past the new item. For example, given a conditional \if@aftersctnhead set true when you’re at a section heading, you could do:

\hookaction{afterindexterm}{\if@aftersctnhead \nobreak \fi}

4.12.1.2 Modifying index entries

All the index commands described in the previous section take an initial optional argument before the index term, which modify the index entry’s meaning in various ways. You can specify only one of the following in any given command, except that begin and end can be specified together with pagemarkup=cs (separate them with a comma without a following space, like this: [begin,pagemarkup=defn]).

These work via MakeIndex’s “encapsulation” feature. See Customizing indexing, if you’re not using the default characters for the MakeIndex operators. The other optional argument (specifying a subterm) is independent of these.

Here are the possibilities:

begin
end

These mark an index entry as the beginning or end of a range. The index entries must match exactly for MakeIndex to recognize them. Example:

\sidx[begin]{future}[Cohen, Leonard]
...
\sidx[end]{future}[Cohen, Leonard]

will typeset as something like

future,
  Cohen, Leonard, 65–94
see

This marks an index entry as pointing to another; the real index term is an additional (non-optional) argument to the command. Thus you can anticipate a term readers may wish to look up, yet which you have decided not to index. Example:

\sidx[see]{analysis}[archetypal]{archetypal criticism}

becomes

analysis,
  archetypal, see archetypal criticism
seealso

Similar to see (the previous item), but also allows for normal index entries of the referencing term. The normal index entries have to be created separately—seealso does not contribute a page number to the index entry. For example, if you have indexed a term on pages 75, 97 and 114, and then add a seealso entry for the term:

\sidx[seealso]{archetypal criticism}[elements of]{dichotomies}

the index will contain

archetypal criticism,
  elements of, 75, 97, 114, see also dichotomies

(Aside for the academically curious: The archetypal critical book I took these dichotomous examples from is Laurence Berman’s The Musical Image, which I happened to co-design and typeset.)

pagemarkup=cs

This puts \cs before the page number in the typeset index, thus allowing you to underline definitive entries, italicize examples, and the like. You do not precede the control sequence cs with a backslash. (That just leads to expansive difficulties.) Naturally it is up to you to define the control sequences you want to use. Example:

\def\defn#1{{\sl #1}}
\sidx[pagemarkeup=defn]{indexing}

becomes something like

indexing, \defn{75}

4.12.1.3 Index entries with special characters

Indexing terms with special characters can become quite cumbersome because you have to keep both TeX and MakeIndex happy at the same time. For example, while ‘!’ has no special meaning for TeX, it is a subentry separator for MakeIndex, therefore you’d have to escape occurrences of literal ‘!’ in index terms. Things get even more interesting with characters which are special in both TeX and MakeIndex.

This in turn has some implications for the non-silent forms of the indexing commands (see Indexing terms), since TeX and MakeIndex use different conventions for escaping characters. For example, this will not typeset the exclamation point correctly within the text, while it will come out right inside the index, after MakeIndex strips the quoting character (‘"’):

\idx{"!}

This would have to be rewritten using the silent command:

!\sidx{"!}

In general, it is a good idea to eschew the non-silent commands whenever index term contains anything unusual.

To understand this keep in mind that indexing commands read the terms verbatim so that the terms can embed almost any character, and that’s what gets written into the .idx file. The non-silent forms then typeset the term by rescanning the verbatim copy, hence for the non-silent commands the term, besides being a valid MakeIndex input, must also represent a valid TeX input. The silent commands don’t have this restriction—their terms only need to become valid TeX input after MakeIndex processes the .idx file and writes the .ind file. This is what makes the non-silent commands less powerful and more troublesome when dealing with special characters.

Here’s an example showing that terms for the silent commands can contain almost any character:

\sidx[see]{comments}[with %@with \verbatim %"|endverbatim]
  {commenting with \verbatim %"|endverbatim}

We didn’t have to escape ‘%’ in the sort string for MakeIndex, while we had to put it inside the verbatim environment (see Verbatim listing) in the part which MakeIndex will pass back to TeX. Also, we had to escape the ‘|’ character because it is special for MakeIndex. If you have trouble understanding the reasons for the different types of escaping used, it is best to examine the .idx and .ind files resulting from processing the above input.

As was mentioned, index terms can embed “almost any character”, so now we’ll describe the exceptions.

The following characters are reset to their usual meanings because they are not useful verbatim: multiple consecutive spaces are converted into a single space; ASCII tab characters are treated as spaces; ASCII return is treated as end-of-line (this means, among other things, that long terms can be broken across several lines).

You have to be careful with the begin- and end-group characters (‘{’ and ‘}’ by default). If they are matched, you don’t have to do anything special. For example:

\sidx {braces {, }@braces
  \verbatim {"|endverbatim, \verbatim }"|endverbatim}

However, if they are not matched you have two problems on hand. The first one is TeX—you have to instruct TeX to use something else as begin- and/or end-group characters. Eplain provides an easy way to do this: just define \idxargopen and/or \idxargclose to the begin- and end-group characters you are going to use with indexing macros, and use braces inside index terms without any restrictions. Here’s an example:

\def\idxargopen{`\<}
\def\idxargclose{`\>}
\sidx <left brace "{@left brace \verbatim "{"|endverbatim>

In this example we’ve also dealt with the second problem—braces are MakeIndex’s grouping characters as well (by default), so we have escaped unmatched braces with ‘"’.

And the final note: if you need a subentry containing brackets (‘[’ and ‘]’), avoid the optional argument of \sidx and friends, and use instead MakeIndex’s subentry separator to create the subentry with the brackets in it:

\sidx{entry!subentry with a bracket [}

4.12.1.4 Proofing index terms

As you are reading through a manuscript, it is helpful to see what terms have been indexed, so you can add others, catch miscellaneous errors, etc. (Speaking from bitter experience, I can say it is extremely error-prone to leave all indexing to the end of the writing, since it involves adding many TeX commands to the source files.)

So Eplain puts index terms in the margin of each page, if you set \indexproofingtrue. It is false by default. The terms are typeset by the macro \indexproofterm, which takes a single argument, the term to be typeset. Eplain’s definition of \indexproofterm just puts it into an \hbox, first doing \indexprooffont, which Eplain defines to select the font cmtt8. With this definition long terms run off the page, but since this is just for proofreading anyway, it seems acceptable.

On the other hand, we certainly don’t want the index term to run into the text of the page, so Eplain uses the right-hand side of the page rather than the left-hand page (assuming a language read left to right here). So \ifodd\pageno, Eplain kerns by \outsidemargin, otherwise by \insidemargin. If those macros are undefined, \indexsetmargins defines them to be one inch plus \hoffset.

To get the proofing index entries on the proper page, Eplain defines a new insertion class \@indexproof. To unbox any index proofing material, Eplain redefines \makeheadline to call \indexproofunbox before the original \makeheadline. Thus, if you have your own output routine, that redefines or doesn’t use \makeheadline, it’s up to you to call \indexproofunbox at the appropriate time.


4.12.2 Typesetting an index

The command \readindexfile{i} reads and typesets the .ind file that MakeIndex outputs (from the .idx file which the indexing commands in the previous sections write). Eplain defines a number of commands that support the default MakeIndex output.

More precisely, \readindexfile reads \indexfilebasename.index-letternd, where the index-letter is the argument. \indexfilebasename is \jobname by default, but if you have different indexes in different parts of a book, you may wish to change it, just as with bibliographies (see Citations and bibliographies).

MakeIndex was designed to work with LaTeX; therefore, by default the .ind file starts with \begin{theindex} and ends with \end{theindex}. If no \begin has been defined, Eplain defines one to ignore its argument and set up for typesetting the index (see below), and also defines a \end to ignore its argument. (In a group, naturally, since there is a primitive \end).

Eplain calls \indexfonts, sets \parindent = 0pt, and does \doublecolumns (see Multiple columns) at the \begin{theindex}. \indexfonts does nothing by default; it’s just there for you to override. (Indexes are usually typeset in smaller type than the main text.)

It ends the setup with \hookrun{beginindex}, so you can override anything you like in that hook (see Hooks). For example:

\hookaction{beginindex}{\triplecolumns}

MakeIndex turns each main index entry into an \item, subentries into \subitem, and subsubentries into \subsubitem. By default, the first line of main entries are not indented, and subentries are indented 1em per level. Main entries are preceded by a \vskip of \aboveitemskipamount, 0pt plus2pt by default. Page breaks are encouraged before main entries (\penalty -100), but prohibited afterwards—Eplain has no provision for “continued” index entries.

All levels do the following:

\hangindent = 1em
\raggedright
\hyphenpenalty = 10000

Each entry ends with \hookrun{indexitem}, so you can change any of this. For example, to increase the allowable rag:

\hookaction{indexitem}{\advance\rightskip by 2em}

Finally, MakeIndex outputs \indexspace between each group of entries in the .ind file. Eplain makes this equivalent to \bigbreak.


4.12.3 Customizing indexing

By default, MakeIndex outputs ‘, ’ after each term in the index. To change this, you can add the following to your MakeIndex style (.ist) file:

delim_0 "\\afterindexterm "
delim_1 "\\afterindexterm "
delim_2 "\\afterindexterm "

Eplain makes \afterindexterm equivalent to \quad.

You can also change the keywords Eplain recognizes (see Modifying index entries):

\idxrangebeginword

‘begin’

\idxrangeendword

‘end’

\idxseecmdword

‘see’

\idxseealsocmdword

‘seealso’

You can also change the magic characters Eplain puts into the .idx file, in case you’ve changed them in the .ist file:

\idxsubentryseparator

!

\idxencapoperator

|

\idxbeginrangemark

(

\idxendrangemark

)

There is no macro for the actual (‘@’ by default) character, because it’s impossible to make it expand properly.

You can change the (imaginary) page number that “see also” entries sort as by redefining \idxmaxpagenum. This is 99999 by default, which is one digit too many for old versions of MakeIndex.

The words output by Eplain for “see” and “see also” index entries are defined by \indexseeword and \indexseealsowords respectively. You can change the typeface used for these words by redefining \seevariant. And finally, the macros \indexsee and \indexseealso actually produce the “see …” entries, so you can redefine them if you want something entirely different. If you do redefine them, make them take two parameters, the term being referenced and the \idxmaxpagenum (the latter should normally be ignored). See the example below.

Unfortunately, it is impossible to reliably control the commas produced by MakeIndex in front of “see …” entries in the .ind file, either at MakeIndex level or at Eplain level. However, the sed script contained in trimsee distributed with Eplain in the util directory can be used to filter out these commas from the output of MakeIndex. For example, suppose you want the following style for your “see …” entries:

analysis,
  archetypal (see archetypal criticism)
archetypal criticism,
  elements of, 75, 97, 114 (see also dichotomies)

You would need to redefine these macros in your TeX file:

\def\indexsee#1#2{({\seevariant \indexseeword\/ }#1)}
\def\indexseealso#1#2{({\seevariant \indexseealsowords\/ }#1)}

and then filter out the commas in front of the “see …” entries by running the following command to produce the .ind file (assuming the name of the .idx file is myfile.idx and the trimsee script is placed in the current directory):

$ cat myfile.idx | makeindex | ./trimsee >myfile.ind

By default, trimsee uses default page list separators and default “see …” command names. If you set up MakeIndex to use different page list separator or change the names of \indexsee and \indexseealso commands, it is possible to adjust the trimsee script through its command line options, which are the following:

-i is

Use is as a regular expression matching separator before “see …” commands in the input (default: ‘, \+’).

-o os

Use os as a separator to replace is before “see …” commands (default: ‘ ’).

-s see

Use see as a regular expression matching “see …” commands (default: ‘\\indexsee’).

-h
--help

Print a usage message.

-v
--version

Print version.

trimsee reads input from the standard input, and directs its output to the standard output.


4.13 Justification

Eplain defines three commands to conveniently justify multiple lines of text: \flushright, \flushleft, and \center.

They all work in the same way; let’s take \center as the example. To start centering lines, you say \center inside a group; to stop, you end the group. Between the two commands, each end-of-line in the input file also starts a new line in the output file.

The entire block of text is broken into paragraphs at blank lines, so all the TeX paragraph-shaping parameters apply in the usual way. This is convenient, but it implies something else that isn’t so convenient: changes to any linespacing parameters, such as \baselineskip, will have no effect on the paragraph in which they are changed. TeX does not handle linespacing changes within a paragraph (because it doesn’t know where the line breaks are until the end of the paragraph).

The space between paragraphs is by default one blank line’s worth. You can adjust this space by assigning to \blanklineskipamount; this (vertical) glue is inserted after each blank line.

Here is an example:

{\center First line.

   Second line, with a blank line before.
}

This produces:

First line.
Second line, with a blank line before.

You may wish to use the justification macros inside of your own macros. Just be sure to put them in a group. For example, here is how a title macro might be defined:

\def\title{\begingroup\titlefont\center}
\def\endtitle{\endgroup}

In addition, Eplain defines \raggedleft, analogous to plain TeX’s \raggedright. This macro is also typically used inside a group, but unlike the environments above, TeX does normal line breaking; that is, ends-of-lines in the input file aren’t treated specially. Just like plain’s \raggedright, it also resets \spaceskip and \xspaceskip so that interword spacing is uniform. It also sets \parfillskip to zero so that last lines of paragraphs are also “ragged left”. Finally, \leftskip’s new value is taken from a new glue register, \raggedleft; its default value is 0pt plus 2em, the same as \raggedright’s \rightskip.

Here’s an example:

{\raggedleft This text will be set ragged left,
although the left margin won't be too ragged by default.
You may well want to increase the value of
{\tt \char`\\raggedleftskip} before calling the macro.
It's necessary to end the paragraph before ending the group
or the setting won't have any effect, so: {\tt \char`\\par}
}

Despite \raggedleft resetting \parfillskip to zero, TeX’s line breaking may still prefer to make the last line of a paragraph considerably shorter than the rest, to minimize overall badness. Increasing \raggedleftskip may help somewhat, but using \emergencystretch, retaining interword stretchability by assigning \leftskip directly, or even forcing line breaks may be necessary.


4.14 Tables

Eplain provides a single command, \makecolumns, to make generating one particular kind of table easier. More ambitious LaTeX styles and macro packages tackle more difficult applications. The autorows feature of the Memoir package provides similar functionality to this.

Many tables are homogenous, i.e., all the entries are semantically the same. The arrangement into columns is to save space on the page, not to encode different meanings. In this kind of the table, it is useful to have the column breaks chosen automatically, so that you can add or delete entries without worrying about the column breaks.

\makecolumns takes two arguments: the number of entries in the table, and the number of columns to break them into. As you can see from the example below, the first argument is delimited by a slash, and the second by a colon and a space (or end-of-line). The entries for the table then follow, one per line (not including the line with the \makecolumns command itself).

\parindent defines the space to the left of the table. \hsize defines the width of the table. So you can adjust the position of the table on the page by assignments to these parameters, probably inside a group.

You can also control the penalty at a page break before the \makecolumns by setting the parameter \abovecolumnspenalty. Usually, the table is preceded by some explanatory text. You wouldn’t want a page break to occur after the text and before the table, so Eplain sets it to 10000. But if the table produced by \makecolumns is standing on its own, \abovecolumnspenalty should be decreased.

If you happen to give \makecolumns a smaller number of entries than you really have, some text beyond the (intended) end of the table will be incorporated into the table, probably producing an error message, or at least some strange looking entries. And if you give \makecolumns a larger number of entries than you really have, some of the entries will be typeset as straight text, probably also looking somewhat out of place.

Here is an example:

% Arrange 6 entries into 2 columns:
\makecolumns 6/2: % This line doesn't have an entry.
one
two
three
four
five
six
Text after the table.

This produces ‘one’, ‘two’, and ‘three’ in the first column, and ‘four’, ‘five’, and ‘six’ in the second.


4.15 Margins

TeX’s primitives describe the type area in terms of an offset from the upper left corner, and the width and height of the type. Some people prefer to think in terms of the margins at the top, bottom, left, and right of the page, and most composition systems other than TeX conceive of the page laid out in this way. Therefore, Eplain provides commands to directly assign and increment the margins.

\topmargin = dimen
\bottommargin = dimen
\leftmargin = dimen
\rightmargin = dimen

These commands set the specified margin to the dimen given. The = and the spaces around it are optional. The control sequences here are not TeX registers, despite appearances; therefore, commands like \showthe\topmargin will not do what you expect.

\advancetopmargin by dimen
\advancebottommargin by dimen
\advanceleftmargin by dimen
\advancerightmargin by dimen

These commands change the specified margin by the dimen given.

Regardless of whether you use the assignment or the advance commands, Eplain always changes the type area in response, not the other margins. For example, when TeX starts, the left and right margins are both one inch. If you then say \leftmargin = 2in, the right margin will remain at one inch, and the width of the lines (i.e., \hsize) will decrease by one inch.

When you use any of these commands, Eplain computes the old value of the particular margin, by how much you want to change it, and then resets the values of TeX’s primitive parameters to correspond. Unfortunately, Eplain cannot compute the right or bottom margin without help: you must tell it the full width and height of the final output page. It defines two new parameters for this:

\paperheight

The height of the output page; default is 11truein.

\paperwidth

The width of the output page; default is 8.5truein.

If your output page has different dimensions than this, you must reassign to these parameters, as in

\paperheight = 11truein
\paperwidth = 17truein

4.16 Multiple columns

Eplain provides for double, triple, and quadruple column output: say \doublecolumns, \triplecolumns, or \quadcolumns, and from that point on, the manuscript will be set in columns. To go back to one column, say \singlecolumn.

You may need to invoke \singlecolumn to balance the columns on the last page of output.

To do a “column eject”, i.e., move to the top of the next column, do \columnfill. This does not actually force an eject, however: it merely inserts an unbreakable space of (essentially) size \@normalvsize minus \pagetotal (where \@normalvsize is the usual height of the page; to implement multicolumns, Eplain multiplies \vsize itself by the number of columns). In most circumstances, a column break will be forced after this space (during the column splitting operation when the whole page is output).

The columns are separated by the value of the dimen parameter \gutter. Default value is two picas. If you want to add vertical material between the columns, use \gutterbox. For example, to put a vertical line between columns, define \gutterbox as

\def\gutterbox{\vbox to \dimen0{\vfil\hbox{\vrule height\dimen0}\vfil}}%

There are known bugs in the multiple-column code such that \topmark and possibly other marks can have an incorrect value on the last page of multiple-column material when using \singlecolumn to balance the columns. Unfortunately this is quite difficult to fix, and at present (volunteers welcome), it’s going to remain. A suboptimal workaround is to insert \columnfill at the appropriate place.

The dimension counter \dimen0 contains the height of the column.

All the \…columns macros insert the value of the glue parameter \abovecolumnskip before the multicolumn text, and the value of the glue parameter \belowcolumnskip after it. The default value for both of these parameters is \bigskipamount, i.e., one linespace in plain TeX.

The macros take into account only the insertion classes defined by plain TeX; namely, footnotes and \topinserts. If you have additional insertion classes, you will need to change the implementation.

Also, Eplain makes insertions the full page width. There is no provision for column-width insertions.


4.17 Footnotes

The most common reference mark for footnotes is a raised number, incremented on each footnote. The \numberedfootnote macro provides this. It takes one argument, the footnote text.

If your document uses only numbered footnotes, you could make typing \numberedfootnote more convenient with a command such as:

\let\footnote = \numberedfootnote

After doing this, you can type your footnotes as \footnote{footnote text}, instead of as \numberedfootnote{footnote text}.

Eplain keeps the current footnote number in the count register \footnotenumber. So, to reset the footnote number to zero, as you might want to do at, for example, the beginning of a chapter, you could say \footnotenumber=0.

Plain TeX separates the footnote marker from the footnote text by an en space (it uses the \textindent macro). In Eplain, you can change this space by setting the dimension register \footnotemarkseparation. The default is still an en.

You can produce a space between footenotes by setting the glue register \interfootnoteskip. The default is zero.

\parskip is also set to zero by default before the beginning of each footnote (but not for the text of the footnote).

You can also control footnote formatting in a more general way: Eplain expands the token register \everyfootnote before a footnote is typeset, but after the default values for all the parameters have been established. For example, if you want your footnotes to be printed in seven-point type, indented by one inch, you could say:

\everyfootnote = {\sevenrm \leftskip = 1in}

By default, an \hrule is typeset above each group of footnotes on a page. You can control the dimensions of this rule by setting the dimension registers \footnoterulewidth and \footnoteruleheight. The space between the rule and the first footnote on the page is determined by the dimension register \belowfootnoterulespace. If you don’t want any rule at all, set \footenoteruleheight=0pt, and, most likely, \belowfootnoterulespace=0pt. The defaults for these parameters typeset the rule in the same way as plain TeX: the rule is 0.4 points high, 2 true inches wide, with 2.6 points below it.

The space above the rule and below the text on the page is controlled by the glue register \skip\footins. The default is a plain TeX \bigskip.

Eplain can create hypertext links for the footnote marks (see Footnote hyperlinks: foot, footback).


4.18 Fractions

Exercise 11.6 of The TeXbook describes a macro \frac for setting fractions, but \frac never made it into plain TeX. So Eplain includes it.

\frac typesets the numerator and denominator in \scriptfont0, slightly raised and lowered. The numerator and denominator are separated by a slash. The denominator must be enclosed in braces if it’s more than one token long, but the numerator need not be. (This is a consequence of \frac taking delimited arguments; see page 203 of The TeXbook for an explanation of delimited macro arguments.)

For example, \frac 23/{64} turns ‘23/64’ into .


4.19 Paths

When you typeset long pathnames, electronic mail addresses, or other such “computer” names, you would like TeX to break lines at punctuation characters within the name, rather than trying to find hyphenation points within the words. For example, it would be better to break the email address [email protected] at the ‘@’ or a ‘.’, rather than at the hyphenation points in ‘letters’ and ‘alpha’.

If you use the \path macro to typeset the names, TeX will find these good breakpoints. The argument to \path is delimited by any character other than ‘\’ which does not appear in the name itself. ‘|’ is often a good choice, as in:

You can control the exact set of characters at which breakpoints will be allowed by calling \discretionaries. This takes the same sort of delimited argument; any character in the argument will henceforth be a valid breakpoint within \path. The default set is essentially all the punctuation characters:

\discretionaries |~!@$%^&*()_+`-=#{}[]:";'<>,.?\/|

If for some reason you absolutely must use \ as the delimiter character for \path, you can set \specialpathdelimiterstrue. (Other delimiter characters can still be used.) TeX then processes the \path argument about four times more slowly.

The \path macro comes from path.sty, written by Nelson Beebe and Philip Taylor, and available at https://ctan.org/pkg/path.


4.20 Logos

Eplain redefines the \TeX macro of plain TeX to end with \null, so that the proper spacing is produced when \TeX is used at the end of a sentence. The other …TeX macros listed here do this, also.

Eplain defines \AMSLaTeX, \AMSTeX, \BibTeX \eTeX, \ExTeX, \LAMSTeX, \LaTeX, \MF, \SLiTeX, \XeLaTeX, and \XeTeX to produce their respective logos. (Sorry, the logos are not shown here.) Some spelling variants of these are also supported.

Most of these macros come from texnames.sty, compiled by Nelson Beebe and available at https://mirror.ctan.org/info/biblio/texnames.sty (part of the biblio package, https://ctan.org/pkg/biblio).


4.21 Boxes

The solid rectangle that Eplain uses as a marker in unordered lists (see Lists) is available by itself: just say \blackbox.

You can create black boxes of arbitrary size with \hrule or \vrule.

You can also get unfilled rectangles with \makeblankbox. This takes two explicit arguments: the height and depth of the rules that define the top and bottom of the rectangle. (The two arguments are added to get the width of the left and right borders, so that the thickness of the border is the same on all four sides.) It also uses, as implicit arguments, the dimensions of \box0 to define the dimensions of the rectangle it produces. (The contents of \box0 are ignored.)

Here is an example. This small raised open box is suitable for putting next to numbers in, e.g., a table of contents.

\def\openbox{%
  \ht0 = 1.75pt \dp0 = 1.75pt \wd0 = 3.5pt
  \raise 2.75pt \makeblankbox{.2pt}{.2pt}
}

Finally, you can put a box around arbitrary text with \boxit. This takes one argument, which must itself be a (TeX) box, and puts a printed box around it, separated by \boxitspace white space (3 points by default) on all four sides. For example:

\boxit{\hbox{This text is boxed.}}

The reason that the argument must be a box is that when the text is more than one line long, TeX cannot figure out the line length for itself. Eplain does set \parindent to zero inside \boxit, since it is very unlikely you would want indentation there. (If you do, you can always reset it yourself.)

\boxit uses \ehrule and \evrule so that you can easily adjust the thicknesses of the box rules. See Rules.


4.22 Checking for PDF output

You might sometimes want to test whether the target format is .pdf or .dvi. The \ifpdf conditional can be used for this:

\ifpdf
   This text is produced when the engine outputs PDF.
\else
   This text is produced when the engine outputs DVI (or similar).
\fi

At this writing, \ifpdf will be true when running pdfTeX or LuaTeX with PDF output. It will be false when running XeTeX, or (of course) original TeX, etc.

Eplain defines \ifpdf by incorporating iftex.sty, a package now maintained by the LaTeX Project Team. iftex.sty, and therefore Eplain, defines numerous related conditionals to test for different engines; see its package documentation for details: https://ctan.org/pkg/ifpdf.


4.23 Loading LaTeX packages

Eplain provides a limited support for loading LaTeX packages (.sty files—not .cls). This will mostly work for packages which were designed with plain TeX compatibility in mind, which means that most LaTeX packages cannot be loaded. The packages which are known to work are listed below (see Packages known to work). If you discover a working package which is not in the list, please report it to the Eplain mailing list (see Introduction).

To set up a pseudo-LaTeX environment for the packages, Eplain uses miniltx.tex (https://ctan.org/pkg/miniltx) from the LaTeX graphics collection, written by David Carlisle and Sebastian Rahtz. Eplain extends miniltx.tex to provide (primarily) support for package options; in many cases, you can use miniltx.tex directly without loading Eplain at all.


4.23.1 The \usepackage command

\usepackage loads a LaTeX package. Its syntax is similar to that of LaTeX’s \usepackage command:

\usepackage[options]{packages}[version]

where options is a comma-separated list of package options, packages is a comma-separated list of packages to load (without the .sty suffix), and version is a package version number given as a date in the format ‘YYYY/MM/DD’. If an older version of the package is found, a warning is issued. If several packages are loaded within a single \usepackage command, the options will be applied to each of the packages. As usual, parameters in square brackets are optional and can be omitted (together with the square brackets).

For example:

\usepackage[foo,bar]{pack1,pack2}[2005/08/29]

will load packages ‘pack1’ and ‘pack2’, each with the options ‘foo’ and ‘bar’, and will check that each of the packages are dated 2005/08/29 or newer.


4.23.2 Environment for loading packages

Some packages request that certain commands are executed after all packages have been loaded. In LaTeX, this means that the commands are executed at the beginning of the document, after the so-called preamble. Neither plain TeX nor Eplain have a concept of preamble; therefore, Eplain requires that all packages be loaded inside a \beginpackages...\endpackages block. For example:

\beginpackages
  \usepackage[foo,bar]{pack1}
  \usepackage{pack2}
\endpackages

This requirement enables Eplain to execute the “delayed” commands at the end of the \beginpackages...\endpackages block.

For the same reason, it is advisable to specify only one such block per document, just like there is only one preamble in LaTeX.

Both the miniltx.tex file used by Eplain and some LaTeX packages redefine TeX’s primitive \input to be a macro. Under plain TeX, users probably expect the primitive \input. Therefore, at the beginning of the \beginpackages...\endpackages block Eplain saves the meaning of \input as \eplaininput and restores the original \input at the end of the block. This usually means that the primitive \input is restored, unless you (or some other macro package you’ve loaded directly) have redefined it before calling \beginpackages. In case you need to access the package-provided \input, Eplain saves it as \packageinput.

Along the same lines, Eplain restores the catcode of ‘@’ at \endpackages to whatever it was before (using \resetatcatcode, as defined by miniltx.tex). This is needed because miniltx.tex, read by \beginpackages, does not restore the catcode of ‘@’, but leaves it as 11 (letter).

Sometimes you may encounter packages which make conflicting redefinitions of \input. Common symptoms are TeX spewing incomprehensible error messages or hanging in a loop at a call to \input. This sometimes can be cured by restoring \input to \eplaininput before loading each package. For example:

\beginpackages
  \usepackage{pack1}
  \let\input\eplaininput
  \usepackage{pack2}
\endpackages

4.23.3 Packages known to work

The following table lists packages that had been tested and are known to work with Eplain, and locations where you can find manuals for these packages. Some of the short descriptions of the packages were taken from the documentation for those packages.

autopict (‘2001/06/04 v1.1j Picture mode autoload file’)

https://tug.org/eplain/misc/ltpictur.pdf

This is the LaTeX “picture mode”, started by \begin{picture} and ended by \end{picture} (in LaTeX, this package is not explicitly loaded since it is part of the LaTeX kernel). It provides commands to draw simple figures inside your document without resorting to any external tools.

color (‘1999/02/16 v1.0i Standard LaTeX Color (DPC)’)
graphics (‘2001/07/07 v1.0n Standard LaTeX Graphics (DPC,SPQR)’)
graphicx (‘1999/02/16 v1.0f Enhanced LaTeX Graphics (DPC,SPQR)’)

https://ctan.org/pkg/graphics

These packages are from the LaTeX graphics collection. (The independent xcolor package does not work with Eplain.) They provide commands for changing text/page colors, text rotation and scaling, and much more.

Warning 1: If you encounter problems loading one of these packages under pdfTeX (when pdfTeX reads supp-mis.tex), the cause may be an outdated supp-mis.tex (part of ConTeXt, a typesetting system for TeX) installed on your system. The problem was fixed in supp-mis.tex version 2004.10.26. You can obtain up-to-date versions of supp-mis.tex and the accompanying supp-pdf.tex from https://mirror.ctan.org/macros/pdftex/graphics. To convince TeX to use the new files, you have the following options:

  1. put the new files in the same directory with your document;
  2. overwrite the outdated files installed by your TeX distribution;
  3. install the new supp-mis.tex and supp-pdf.tex files in the relevant subdirectory of your local texmf tree (for info on TeX directory structure, see https://tug.org/tds/);
  4. upgrade your ConTeXt installation.

Note that option 1 is the safest but provides the fix only for your current document. Options 2 and 3 will usually suffice for Eplain but may break ConTeXt. Option 4 is the most general but is more complicated than the first three. Be sure to backup any files you overwrite. Also keep in mind that upgrading your TeX distribution may overwrite files you install in the system texmf tree.
End of warning 1.

Warning 2: If you encounter problems using the \pagecolor command from the color.sty package under pdfTeX, the cause may be an outdated pdfTeX color and graphics driver pdftex.def. The problem was fixed in pdftex.def version 0.03p. You can obtain an up-to-date version from https://ctan.org/pkg/graphics-def.
End of warning 2.

The \fcolorbox macro provided by the color package requires the macro \fbox to work, but miniltx does not provide that. Here is a definition for it that uses Eplain’s \boxit (see Boxes), thanks to Dan Luecking and Helmut Jarausch:

\makeatletter
\def\fbox#1{{%
  \hruledefaultheight=\fboxrule
  \hruledefaultdepth=0pt
  \vruledefaultwidth=\fboxrule
  \let\boxitspace\fboxsep % use miniltx register
  \boxit{\color@begingroup\hbox{#1}\color@endgroup}%
}}
\makeatother

The graphics/graphicx packages have the option draft which instructs \includegraphics not to include the graphics but instead typeset a box with the dimensions of the graphics and the name of the graphics file in typewriter type at the center of the box. These packages expect the LaTeX-provided command \ttfamily to switch to typewriter type. This command is not defined by miniltx.tex, therefore Eplain defines it and makes it equivalent to plain TeX’s \tt.

See Hyperlinks (xhyper.tex), for the demonstration of text rotation and graphics inclusion using the graphicx package, and using the color package to colorize hypertext links.

Klaus Höppner has written a nice introduction to the LaTeX graphics packages and different graphics formats. You can download it from

epstopdf (‘2009/07/16 v2.2 Conversion with epstopdf on the fly (HO)’)

https://ctan.org/pkg/epstopdf-pkg

This package does on-the-fly conversion of Encapsulated PostScript (EPS) graphics into Portable Document Format (PDF) graphics for inclusion with the \includegraphics command from the graphics/graphicx packages, so that you do not have to explicitly call the epstopdf script.

psfrag (‘1998/04/11 v3.04 PSfrag (MCG)’)

https://ctan.org/pkg/psfrag

PSfrag allows the user to precisely overlay Encapsulated PostScript (EPS) files with arbitrary (La)TeX constructions. In order to accomplish this, the user places a simple text “tag” in the graphics file, as a “position marker” of sorts. Then, using simple (La)TeX commands, the user instructs PSfrag to remove that tag from the figure, and replace it with a properly sized, aligned, and rotated (La)TeX equation.

soul (‘2003/11/17 v2.4 letterspacing/underlining (mf)’)

https://ctan.org/pkg/soul

This package provides hyphenatable letterspacing (spacing out), underlining, and some derivatives. The package is optimized for LaTeX, but works with plain TeX—you don’t actually need to load it with the \usepackage command, just say \input soul.sty. If you intend to use the highlighting macros of soul, don’t forget to load the color package.

url (‘2005/06/27 ver 3.2 Verb mode for urls, etc.’)

https://ctan.org/pkg/url

This package provides a form of \verbatim that allows line breaks at certain characters or combinations of characters, accepts reconfiguration, and can usually be used in the argument to another command. It is intended for email addresses, hypertext links, directories/paths, etc., which normally have no spaces.

Eplain can create hypertext links with the \url command (see URL hyperlinks: url).

Be sure to get a version dated at least 2005/06/27, as older versions have problems in plain TeX.


4.23.4 Packages known not to work

The following packages are known not to work with Eplain:

hyperref

https://ctan.org/pkg/hyperref

This package depends heavily on LaTeX, so that it is essentially unusable outside of LaTeX. Eplain provides its own macros for creating hyperlinks; see Hyperlinks.

microtype (‘2013/05/23 v2.51 Micro-typographical refinements (RS)’)

https://ctan.org/pkg/microtype

pict2e (‘2005/07/15 v0.2r Improved picture commands (HjG,RN)’)

https://ctan.org/pkg/pict2e

xcolor (‘2005/06/06 v2.03 LaTeX color extensions (UK)’)

https://ctan.org/pkg/xcolor


6 Arrow theoretic diagrams

This chapter describes definitions for producing commutative diagrams.

Steven Smith wrote this documentation (and the macros).


6.1 Slanted lines and vectors

The macros \drawline and \drawvector provide the capability found in LaTeX’s picture mode to draw slanted lines and vectors of certain directions. Both of these macros take three arguments: two integer arguments to specify the direction of the line or vector, and one argument to specify its length. For example, ‘\drawvector(-4,1){60pt}’ produces the vector which lies in the 2d quadrant, has a slope of minus 1/4, and a width of 60 pt.

Note that if an \hbox is placed around \drawline or \drawvector, then the width of the \hbox will be the positive dimension specified in the third argument, except when a vertical line or vector is specified, e.g., \drawline(0,1){1in}, which has zero width. If the specified direction lies in the 1st or 2d quadrant (e.g., (1,1) or (-2,3)), then the \hbox will have positive height and zero depth. Conversely, if the specified direction lies in the 3d or 4th quadrant (e.g., (-1,-1) or (2,-3)), then the \hbox will have positive depth and zero height.

There are a finite number of directions that can be specified. For \drawline, the absolute value of each integer defining the direction must be less than or equal to six, i.e., (7,-1) is incorrect, but (6,-1) is acceptable. For \drawvector, the absolute value of each integer must be less than or equal to four. Furthermore, the two integers cannot have common divisors; therefore, if a line with slope 2 is desired, say (2,1) instead of (4,2). Also, specify (1,0) instead of, say, (3,0) for horizontal lines and likewise for vertical lines.

Finally, these macros depend upon the LaTeX font line10. If your site doesn’t have this font, ask your system administrator to get it. Future enhancements will include macros to draw dotted lines and dotted vectors of various directions.


6.2 Commutative diagrams

The primitive commands \drawline and \drawvector can be used to typeset arrow theoretic diagrams. This section describes (1) macros to facilitate typesetting arrows and morphisms, and (2) macros to facilitate the construction of commutative diagrams. All macros described in this section must be used in math mode.


6.2.1 Arrows and morphisms

The macros \mapright and \mapleft produce right and left pointing arrows, respectively. Use superscript (^) to place a morphism above the arrow, e.g., ‘\mapright^\alpha’; use subscript (_) to place a morphism below the arrow, e.g., ‘\mapright_{\tilde l}’. Superscripts and subscripts may be used simultaneously, e.g., ‘\mapright^\pi_{\rm epimor.}’.

Similarly, the macros \mapup and \mapdown produce up and down pointing arrows, respectively. Use \rt to place a morphism to the right of the arrow, e.g., ‘\mapup\rt{\rm id}’; use \lft to place a morphism to the left of the arrow, e.g., ‘\mapup\lft\omega’. \lft and \rt may be used simultaneously, e.g., ‘\mapdown\lft\pi\rt{\rm monomor.}’.

Slanted arrows are produced by the macro \arrow, which takes a direction argument (e.g., ‘\arrow(3,-4)’). Use \rt and \lft to place morphisms to the right and left, respectively, of the arrow. A slanted line (no arrowhead) is produced with the macro \sline, whose syntax is identical to that of \arrow.

The length of these macros is predefined by the default TeX dimensions \harrowlength, for horizontal arrows (or lines), \varrowlength, for vertical arrows (or lines), and \sarrowlength, for slanted arrows (or lines). To change any of these dimensions, say, e.g., ‘\harrowlength=40pt’. As with all other TeX dimensions, the change may be as global or as local as you like. Furthermore, the placement of morphisms on the arrows is controlled by the dimensions \hmorphposn, \vmorphposn, and \morphdist. The first two dimensions control the horizontal and vertical position of the morphism from its default position; the latter dimension controls the distance of the morphism from the arrow. If you have more than one morphism per arrow (i.e., a ^/_ or \lft/\rt construction), use the parameters \hmorphposnup, \hmorphposndn, \vmorphposnup, \vmorphposndn, \hmorphposnrt, \hmorphposnlft, \vmorphposnrt, and \vmorphposnlft. The default values of all these dimensions are provided in the section on parameters that follows below.

There is a family of macros to produce horizontal lines, arrows, and adjoint arrows. The following macros produce horizontal maps and have the same syntax as \mapright:

\mapright

$X\mapright Y$ = (a right arrow).

\mapleft

$X\mapleft Y$

\hline

$X\hline Y$

\bimapright

$X\bimapright Y$

\bimapleft

$X\bimapleft Y$

\adjmapright

$X\adjmapright Y$

\adjmapleft

$X\adjmapleft Y$

\bihline

$X\bihline Y$

There is also a family of macros to produce vertical lines, arrows, and adjoint arrows. The following macros produce vertical maps and have the same syntax as \mapdown:

\mapdown

(a down arrow)

\mapup

(an up arrow)

\vline

(vertical line)

\bimapdown

(two down arrows)

\bimapup

(two up arrows)

\adjmapdown

(two adjoint arrows; down then up)

\adjmapup

(two adjoint arrows; up then down)

\bivline

(two vertical lines)

Finally, there is a family of macros to produce slanted lines, arrows, and adjoint arrows. The following macros produce slanted maps and have the same syntax as \arrow:

\arrow

(a slanted arrow)

\sline

(a slanted line)

\biarrow

(two straight arrows)

\adjarrow

(two adjoint arrows)

\bisline

(two straight lines)

The width between double arrows is controlled by the parameter \channelwidth. The parameters \hchannel and \vchannel, if nonzero, override \channelwidth by controlling the horizontal and vertical shifting from the first arrow to the second.

There are no adornments on these arrows to distinguish inclusions from epimorphisms from monomorphisms. Many texts, such as Lang’s book Algebra, use as a tasteful alternative the symbol ‘inc’ (in roman) next to an arrow to denote inclusion.

Future enhancements will include a mechanism to draw curved arrows found in, e.g., the Snake Lemma, by employing a version of the \path macros of Appendix D of The TeXbook.


6.2.2 Construction of commutative diagrams

There are two approaches to the construction of commutative diagrams described here. The first approach, and the simplest, treats commutative diagrams like fancy matrices, as Knuth does in Exercise 18.46 of The TeXbook. This case is covered by the macro \commdiag, which is an altered version of the Plain TeX macro \matrix. An example suffices to demonstrate this macro. The following commutative diagram (illustrating the covering homotopy property; Bott and Tu, Differential Forms in Algebraic Topology) is produced with the code

$$\commdiag{Y&\mapright^f&E\cr \mapdown&\arrow(3,2)\lft{f_t}&\mapdown\cr
Y\times I&\mapright^{\bar f_t}&X}$$

Of course, the parameters may be changed to produce a different effect. The following commutative diagram (illustrating the universal mapping property; Warner, Foundations of Differentiable Manifolds and Lie Groups) is produced with the code

$$\varrowlength=20pt
\commdiag{V\otimes W\cr \mapup\lft\phi&\arrow(3,-1)\rt{\tilde l}\cr
V\times W&\mapright^l&U\cr}$$

A diagram containing isosceles triangles is achieved by placing the apex of the triangle in the center column, as shown in the example (illustrating all constant minimal realizations of a linear system; Brockett, Finite Dimensional Linear Systems) which is produced with the code

$$\sarrowlength=.42\harrowlength
\commdiag{&R^m\cr &\arrow(-1,-1)\lft{\bf B}\quad \arrow(1,-1)\rt{\bf G}\cr
R^n&\mapright^{\bf P}&R^n\cr
\mapdown\lft{e^{{\bf A}t}}&&\mapdown\rt{e^{{\bf F}t}}\cr
R^n&\mapright^{\bf P}&R^n\cr
&\arrow(1,-1)\lft{\bf C}\quad \arrow(-1,-1)\rt{\bf H}\cr
&R^q\cr}$$

Other commutative diagram examples appear in the file commdiags.tex, which is distributed with this package.

In these examples the arrow lengths and line slopes were carefully chosen to blend with each other. In the first example, the default settings for the arrow lengths are used, but a direction for the arrow must be chosen. The ratio of the default horizontal and vertical arrow lengths is approximately the golden mean the arrow direction closest to this mean is (3,2). In the second example, a slope of is desired and the default horizontal arrow length is 60 pt; therefore, choose a vertical arrow length of 20 pt. You may affect the interline glue settings of \commdiag by redefining the macro \commdiagbaselines. (cf. Exercise 18.46 of The TeXbook and the section on parameters below.)

The width, height, and depth of all morphisms are hidden so that the morphisms’ size do not affect arrow positions. This can cause a large morphism at the top or bottom of a diagram to impinge upon the text surrounding the diagram. To overcome this problem, use TeX’s \noalign primitive to insert a \vskip immediately above or below the offending line, e.g., ‘$$\commdiag{\noalign{\vskip6pt}X&\mapright^\int&Y\cr ...}’.

The macro \commdiag is too simple to be used for more complicated diagrams, which may have intersecting or overlapping arrows. A second approach, borrowed from Francis Borceux’s Diagram macros for LaTeX, treats the commutative diagram like a grid of identically shaped boxes. To compose the commutative diagram, first draw an equally spaced grid, e.g., on a piece of scratch paper. Then draw each element (vertices and arrows) of the commutative diagram on this grid, centered at each grid point. Finally, use the macro \gridcommdiag to implement your design as a TeX alignment. For example, the cubic diagram that appears in Francis Borceux’s documentation can be implemented on a 7 by 7 grid, and is achieved with the code

$$\harrowlength=48pt \varrowlength=48pt \sarrowlength=20pt
\def\cross#1#2{\setbox0=\hbox{$#1$}%
  \hbox to\wd0{\hss\hbox{$#2$}\hss}\llap{\unhbox0}}
\gridcommdiag{&&B&&\mapright^b&&D\cr
&\arrow(1,1)\lft a&&&&\arrow(1,1)\lft d\cr
A&&\cross{\hmorphposn=12pt\mapright^c}{\vmorphposn=-12pt\mapdown\lft f}
&&C&&\mapdown\rt h\cr\cr
\mapdown\lft e&&F&&\cross{\hmorphposn=-12pt\mapright_j}
{\vmorphposn=12pt\mapdown\rt g}&&H\cr
&\arrow(1,1)\lft i&&&&\arrow(1,1)\rt l\cr
E&&\mapright_k&&G\cr}$$

The dimensions \hgrid and \vgrid control the horizontal and vertical spacing of the grid used by \gridcommdiag. The default setting for both of these dimensions is 15 pt. Note that in the example of the cube the arrow lengths must be adjusted so that the arrows overlap into neighboring boxes by the desired amount. Hence, the \gridcommdiag method, albeit more powerful, is less automatic than the simpler \commdiag method. Furthermore, the ad hoc macro \cross is introduced to allow the effect of overlapping arrows. Finally, note that the positions of four of the morphisms are adjusted by setting \hmorphposn and \vmorphposn.

One is not restricted to a square grid. For example, the proof of Zassenhaus’s Butterfly Lemma can be illustrated by the diagram (appearing in Lang’s book Algebra) This diagram may be implemented on a 9 by 12 grid with an aspect ratio of 1/2, and is set with the code

$$\hgrid=16pt \vgrid=8pt \sarrowlength=32pt
\def\cross#1#2{\setbox0=\hbox{$#1$}%
  \hbox to\wd0{\hss\hbox{$#2$}\hss}\llap{\unhbox0}}
\def\l#1{\llap{$#1$\hskip.5em}}
\def\r#1{\rlap{\hskip.5em$#1$}}
\gridcommdiag{&&U&&&&V\cr &&\bullet&&&&\bullet\cr
&&\sarrowlength=16pt\sline(0,1)&&&&\sarrowlength=16pt\sline(0,1)\cr
&&\l{u(U\cap V)}\bullet&&&&\bullet\r{(U\cap V)v}\cr
&&&\sline(2,-1)&&\sline(2,1)\cr
&&\cross{=}{\sline(0,1)}&&\bullet&&\cross{=}{\sline(0,1)}\cr\cr
&&\l{^{\textstyle u(U\cap v)}}\bullet&&\cross{=}{\sline(0,1)}&&
 \bullet\r{^{\textstyle(u\cap V)v}}\cr
&\sline(2,1)&&\sline(2,-1)&&\sline(2,1)&&\sline(2,-1)\cr
\l{u}\bullet&&&&\bullet&&&&\bullet\r{v}\cr
&\sline(2,-1)&&\sline(2,1)&&\sline(2,-1)&&\sline(2,1)\cr
&&\bullet&&&&\bullet\cr &&u\cap V&&&&U\cap v\cr}$$

Again, the construction of this diagram requires careful choices for the arrow lengths and is facilitated by the introduction of the ad hoc macros \cross, \r, and \l. Note also that superscripts were used to adjust the position of the vertices Many diagrams may be typeset with the predefined macros that appear here; however, ingenuity is often required to handle special cases.


6.2.3 Commutative diagram parameters

The following is a list describing the parameters used in the commutative diagram macros. These dimensions may be changed globally or locally.

\harrowlength

(Default: 60 pt) The length of right or left arrows.

\varrowlength

(Default: 0.618\harrowlength) The length of up or down arrows.

\sarrowlength

(Default: 60 pt) The horizontal length of slanted arrows.

\hmorphposn

(Default: 0 pt) The horizontal position of the morphism with respect to its default position. There are also the dimensions \hmorphposnup, \hmorphposndn, \hmorphposnrt, and \hmorphposnlft for ^/_ or \lft/\rt constructions.

\vmorphposn

(Default: 0 pt) The vertical position of the morphism with respect to its default position. There are also the dimensions \vmorphposnup, \vmorphposndn, \vmorphposnrt, and \vmorphposnlft for ^/_ or \lft/\rt constructions.

\morphdist

(Default: 4 pt) The distance of morphisms from slanted lines or arrows.

\channelwidth

(Default: 3 pt) The distance between double lines or arrows.

\hchannel, \vchannel

(Defaults: 0 pt) Overrides \channelwidth. The horizontal and vertical shifts between double lines or arrows.

\commdiagbaselines

(Default: \baselineskip=15pt \lineskip=3pt \lineskiplimit=3pt ) The parameters used by \commdiag for setting interline glue.

\hgrid

(Default: 15 pt) The horizontal spacing of the grid used by \gridcommdiag.

\vgrid

(Default: 15 pt) The vertical spacing of the grid used by \gridcommdiag.


7 Programming definitions

The definitions in this section are only likely to be useful when you are writing nontrivial macros, not when writing a document.


7.1 Category codes

Plain TeX defines \active (as the number 13) for use in changing category codes. Although the author of The TeXbook has “intentionally kept the category codes numeric”, two other categories are commonly used: letters (category code 11) and others (12). Therefore, Eplain defines \letter and \other.

Sometimes it is cleaner to make a character active without actually writing a \catcode command. The \makeactive command takes a character as an argument to make active (and ignores following spaces). For example, here are two commands which both make \ active:

\makeactive\\   \makeactive92

Sometimes you might want to temporarily change the category code of the ‘@’ character to \letter, so that you can use or define macros which are normally inaccessible to the user. For such situations, Eplain provides the \makeatletter command. It sets the category code of ‘@’ to \letter (11) and defines \resetatcatcode to restore the category code to whatever it was before the call to \makeatletter. For example:

\makeatletter
\def\@hidden@macro{This macro cannot normally be
                   called / redefined by the user}
\resetatcatcode

There is also \makeatother which works similarly but sets the category code of ‘@’ to \other (12).

Usually, when you give a definition to an active character, you have to do so inside a group where you temporarily make the character active, and then give it a global definition (cf. the definition of \obeyspaces in The TeXbook). This is inconvenient if you are writing a long macro, or if the character already has a global definition you do not wish to transcend. Eplain provides \letreturn, which defines the usual end-of-line character to be the argument. For example:

\def\mymacro{... \letreturn\myreturn ... }
\mymacro hello
there

The end-of-line between ‘hello’ and ‘there’ causes \myreturn to be expanded.

The TeXbook describes \uncatcodespecials, which makes all characters which are normally “special” into “other” characters, but the definition never made it into plain TeX. Eplain therefore defines it. For notes on the usage, see Verbatim listing.

Finally, \percentchar expands into a literal ‘%’ character. This is useful when you \write TeX output to a file, and want to avoid spurious spaces. For example, Eplain writes a \percentchar after the definition of cross-references. The macros \lbracechar and \rbracechar expand similarly.


7.2 Allocation macros

Plain TeX provides macros that allocate registers of each primitive type in TeX, to prevent different sets of macros from using the same register for two different things. The macros are all named starting with ‘new’, e.g., \newcount allocates a new “count” (integer) register. Such allocations are usually needed only at the top level of some macro definition file; therefore, plain TeX makes the allocation registers \outer, to help find errors. (The error this helps to find is a missing right brace in some macro definition.)

Sometimes, however, it is useful to allocate a register as part of some macro. An outer control sequence cannot be used as part of a macro definition (or in a few other contexts: the parameter text of a definition, an argument to a definition, the preamble of an alignment, or in conditional text that is being skipped). Therefore, Eplain defines “inner” versions of all the allocation macros, named with the prefix ‘inner’: \innernewbox, \innernewcount, \innernewdimen, \innernewfam, \innernewhelp, \innernewif, \innernewinsert, \innernewlanguage, \innernewread,
\innernewskip, \innernewtoks, \innernewwrite.

You can also define non-outer versions of other macros in the same way that Eplain defines the above. The basic macro is called \innerdef:

\innerdef \innername {outername}

The first argument (\innername) to \innerdef is the control sequence that you want to define. Any previous definition of \innername is replaced. The second argument (outername) is the characters in the name of the outer control sequence. (You can’t use the actual control sequence name, since it’s outer!)

If the outer control sequence is named \cs, and you want to define innercs as the inner one, you can use \innerinnerdef, which is just an abbreviation for a call to \innerdef. For example, these two calls are equivalent:

\innerdef\innerproclaim{proclaim}
\innerinnerdef{proclaim}

7.2.1 Scratch registers

It seems worth reiterating here the conventions for scratch registers defined by Knuth for plain TeX, which Eplain inherits and does not change.

  • Registers numbered 0 to 9, and 255, are free for any use. Thus their values must be assumed to be clobbered whenever another macro might get control. Eplain macros do use the scratch registers.
  • First exception: the \count registers 0..9 are used internally by TeX for page numbering and thus are not available for any other use.
  • Second exception: the \box255 register is likewise internally by TeX, to ship out pages. So it’s not available either.
  • By convention, all assignments to the scratch registers 1, 3, 5, 7, and 9 should be \global, and assignments to the others should be non-\global.

For more details on all aspects of register usage, see The TeXbook or any other plain TeX reference.


7.3 Iteration

You can iterate through a comma-separated list of items with \for. Here is an example:

\for\name:=karl,kathy\do{%
   \message{\name}%
}%

This writes ‘karl’ and ‘kathy’ to the terminal. Spaces before or after the commas in the list, or after the :=, are not ignored. To strip leading spaces off the items, use \For:

\For\name:=
   karl,
   kathy\do{%
      \message{\name}%
   }%

Note that trailing spaces are still not ignored.

Both \for and \For expand the first token of the item list fully, so this is equivalent to the above:

\def\namelist{karl,kathy}%
\for\name:=\namelist\do ...

However, this won’t work, either with \for or with \For:

\def\namelist{karl,kathy}%
\For\name:= \namelist\do ...

because \for and \For expand the first token after := which is space, not \namelist.

Eplain provides another kind of loops, which is an extension of plain TeX’s \loop. If you say:

\loop
  loop-text
\if condition
  if-text
\repeat

then loop-text will be repeated as long as condition is satisfied (\if can be any of the TeX’s conditional commands, without the matching \fi). Eplain extends this with the optional else clause:

\loop
  loop-text
\if condition
  if-text
\else
  else-text
\repeat

Here, loop-text will be repeated as long as condition is not satisfied. This extension is from Victor Eijkhout’s TeX by Topic (page 104).


7.4 Macro arguments

It is occasionally useful to redefine a macro that takes arguments to do nothing. Eplain defines \gobble, \gobbletwo, and \gobblethree to swallow one, two, and three arguments, respectively.

For example, if you want to produce a “short” table of contents—one that includes only chapters, say—the easiest thing to do is read the entire .toc file (see Contents), and just ignore the commands that produce section or subsection entries. To be specific:

\let\tocchapterentry = \shorttocchapter
\let\tocsectionentry = \gobbletwo
\let\tocsubsectionentry = \gobbletwo
\readtocfile

(Of course, this assumes you only have chapters, sections, and subsections in your document.)

In addition, Eplain defines \eattoken to swallow the single following token, using \let. Thus, \gobble followed by ‘{…}’ ignores the entire brace-enclosed text. \eattoken followed by the same ignores only the opening left brace.

Eplain defines a macro \identity which takes one argument and expands to that argument. This may be useful if you want to provide a function for the user to redefine, but don’t need to do anything by default. (For example, the default definition of \eqconstruct (see Formatting equation references) is \identity.)

You may also want to read an optional argument. The established convention is that optional arguments are put in square brackets, so that is the syntax Eplain recognizes. Eplain ignores space tokens before and after optional arguments, via \futurenonspacelet.

You test for an optional argument by using \@getoptionalarg. It takes one argument, a control sequence to expand after reading the argument, if present. If an optional argument is present, the control sequence \@optionalarg expands to it; otherwise, \@optionalarg is \empty. You must therefore have the category code of @ set to 11 (letter). Here is an example:

\catcode`@=\letter
\def\cmd{\@getoptionalarg\finishcmd}
\def\finishcmd{%
  \ifx\@optionalarg\empty
    % No optional argument present.
  \else
    % One was present.
  \fi
}

It’s possible to define macros that appear to accept optional arguments intermixed with mandatory arguments in any imaginable way. For example:

\makeatletter
% \mo{m}[o]
\def\mo#1{\def\mo@arg{#1}\@getoptionalarg\fin@mo}
\def\fin@mo{\vskip1pc
  ARG:    \mo@arg       \par
  OPTARG: \@optionalarg \par
}
% \mom{m}[o]{m}
\def\mom#1{\def\mom@arg{#1}\@getoptionalarg\fin@mom}
\def\fin@mom#1{\vskip1pc
  ARG1:   \mom@arg      \par
  OPTARG: \@optionalarg \par
  ARG2:   #1\par
}
% \omo[o]{m}[o]
\def\omo{\@getoptionalarg\fin@omo}
\def\fin@omo#1{\let\omo@optarg\@optionalarg
               \def\omo@arg{#1}\@getoptionalarg\@fin@omo}
\def\@fin@omo{\vskip1pc
  OPTARG1: \omo@optarg   \par
  ARG:     \omo@arg      \par
  OPTARG2: \@optionalarg \par
}
\makeatother

If an optional argument contains another optional argument, the inner one will need to be enclosed in braces, so TeX does not mistake the end of the first for the end of the second.


7.5 Converting to characters

Eplain defines \xrlabel to produce control sequence names for cross-reference labels, et al. This macro expands to its argument with an ‘_’ appended. (It does this because the usual use of \xrlabel is to generate a control sequence name, and we naturally want to avoid conflicts between control sequence names.)

Because \xrlabel is fully expandable, to make a control sequence name out of the result you need only do

\csname \xrlabel{label}\endcsname

The \csname primitive makes a control sequence name out of any sequence of character tokens, regardless of category code. Labels can therefore include any characters except for ‘\’, ‘{’, ‘}’, and ‘#’, all of which are used in macro definitions themselves.

\sanitize takes a control sequence as an argument and converts the expansion of the control sequence into a list of character tokens. This is the behavior you want when writing information like chapter titles to an output file. For example, here is part of the definition of \writenumberedtocentry; #2 is the title that the user has given.

...
\def\temp{#2}%
...
  \write\tocfile{%
    ...
    \sanitize\temp
    ...
  }%

7.6 Expansion

This section describes some miscellanous macros for expansion, etc.


7.6.1 \csn and \ece

\csn{name} simply abbreviates \csname name \endcsname, thus saving some typing. The extra level of expansion does take some time, though, so I don’t recommend it for an inner loop.

\ece{token}{name} abbreviates

\expandafter token \csname name \endcsname

For example,

\def\fontabbrevdef#1#2{\ece\def{@#1font}{#2}}
\fontabbrevdef{normal}{ptmr}

defines a control sequence \@normalfont to expand to ptmr.


7.6.2 \edefappend

\edefappend is a way of adding on to an existing definition. It takes two arguments: the first is the control sequence name, the second the new tokens to append to the definition. The second argument is fully expanded (in the \edef that redefines the control sequence).

For example:

\def\foo{abc}
\def\bar{xyz}
\edefappend\foo{\bar karl}

results in \foo being defined as ‘abcxyzkarl’.


7.6.3 Hooks

A hook is simply a name for a group of actions which is executed in certain places—presumably when it is most useful to allow customization or modification. TeX already provides many builtin hooks; for example, the \every … token lists are all examples of hooks.

Eplain provides several macros for adding actions to hooks. They all take two arguments: the name of the hook and the new actions.

hookaction name actions
hookappend name actions
hookprepend name actions

Each of these adds actions to the hook name. (Any previously-defined actions are retained.) name is not a control sequence, but rather the characters of the name.

hookactiononce name \cs

\hookactiononce adds cs to name, like the macros above, but first it adds

\global\let \cs \relax

to the definition of \cs. (This implies \cs must be a true expandable macro, not a control sequence \let to a primitive or some other such thing.) Thus, \cs is expanded the next time the hook name is run, but it will disappear after that.

The \global is useful because \hookactiononce is most useful when the grouping structure of the TeX code could be anything. Neither this nor the other hook macros do global assignments to the hook variable itself, so TeX’s usual grouping rules apply.

The companion macro to defining hook actions is \hookrun, for running them. This takes a single argument, the name of the hook. If no actions for the hook are defined, no error ensues.

Here is a skeleton of general \begin and \end macros that run hooks, and a couple of calls to define actions. The use of \hookprepend for the begin action and \hookappend for the end action ensures that the actions are executed in proper sequence with other actions (as long as the other actions use \hookprepend and \hookappend also).

\def\begin#1{ ... \hookrun{begin} ... }
\def\end#1{ ... \hookrun{end} ... }
\hookprepend{begin}\start_underline
\hookappend{end}\finish_underline

7.6.4 Properties

A property is a name/value pair associated with another symbol, traditionally called an atom. Both atom and property names are control sequence names.

Eplain provides two macros for dealing with property lists: \setproperty and \getproperty.

\setproperty atom propname value

\setproperty defines the property property on the atom atom to be value. atom and propname can be anything acceptable to \csname. value can be anything.

\getproperty atom propname

\getproperty expands to the value stored for propname on atom. If propname is undefined, it expands to nothing (i.e., \empty).

The idea of properties originated in Lisp (I believe). There, the implementation truly does associate properties with atoms. In TeX, where we have no builtin support for properties, the association is only conceptual.

The following example typesets ‘xyz’.

\setproperty{a}{pr}{xyz}
\getproperty{a}{pr}

7.6.5 \expandonce

\expandonce is defined as \expandafter\noexpand. Thus, \expandonce token expands token once, instead of to TeX primitives. This is most useful in an \edef.

For example, the following defines \temp to be \foo, not ‘abc’.

\def\foo{abc}
\def\bar{\foo}
\edef\temp{\expandonce\bar}

7.6.6 \ifundefined

\ifundefined{cs} t \else f \fi expands the t text if the control sequence \cs is undefined or has been \let to \relax, and the f text otherwise.

Since \ifundefined is not a primitive conditional, it cannot be used in places where TeX might skip tokens “at high speed”, e.g., within another conditional—TeX can’t match up the \if’s and \fi’s.

This macro was taken directly from The TeXbook, page 308.


7.6.7 \ifempty

\ifempty{arg} t \else f \fi expands the t text if arg is the empty string, and the f text otherwise. This macro is useful when you need to test for empty arguments to your macros, for example:

\def\foo#1{\ifempty{#1} t \else f \fi}

Since \ifempty is not a primitive conditional, it cannot be used in places where TeX might skip tokens “at high speed”, e.g., within another conditional—TeX can’t match up the \if’s and \fi’s.

Note that the following code

\def\empty{}
\ifempty\empty\message{empty}\else\message{not empty}\fi

will produce the message ‘not empty’.


7.6.8 \ifinteger and \isinteger

\ifinteger{arg} t \else f \fi expands the t text if arg is an integer, and the f text otherwise. This macro can detect positive and negative integers.

Since \ifinteger is not a primitive conditional, it cannot be used in places where TeX might skip tokens “at high speed”, e.g., within another conditional—TeX can’t match up the \if’s and \fi’s. For such situations Eplain provides \isinteger, which can be used as follows:

\if\isinteger{arg} t \else f \fi

Although \ifinteger and \isinteger work well with regular input, they are not bullet-proof. For example, the following code

\ifinteger{12_ab}integer\else not integer\fi

will expand to ‘ab_integer’ (and thus would not even compile outside math mode).

These macros come from the TeX Frequently Asked Questions (https://texfaq.org).


7.6.9 \futurenonspacelet

The \futurelet primitive allows you to look at the next token from the input. Sometimes, though, you want to look ahead while ignoring any spaces. This is what \futurenonspacelet does. It is otherwise the same as \futurelet: you give it two control sequences as arguments, and it assigns the next nonspace token to the first, and then expands the second. For example:

\futurenonspacelet\temp\finishup
\def\finishup{\ifx\temp ...}

7.7 Obeying spaces

\obeywhitespace makes both end-of-lines and space characters in the input be respected in the output. Unlike plain TeX’s \obeyspaces, even spaces at the beginnings of lines turn into blank space.

By default, the size of the space that is produced by a space character is the natural space of the current font, i.e., what \ produces.

Ordinarily, a blank line in the input produces as much blank vertical space as a line of text would occupy. You can adjust this by assigning to the parameter \blanklineskipamount: if you set this negative, the space produced by a blank line will be smaller; if positive, larger.

Tabs are not affected by this routine. In particular, if tabs occur at the beginning of a line, they will disappear. (If you are trying to make TeX do the “right thing” with tabs, don’t. Use a utility program like expand instead.)


7.8 Writing out numbers

\numbername produces the written-out form of its argument, i.e., ‘zero’ through ‘ten’ for the numbers 0–10, and numerals for all others.


7.9 Mode-specific penalties

TeX’s built-in \penalty command simply appends to the current list, no matter what kind of list it is. You might intend a particular penalty to always be a “vertical” penalty, however, i.e., appended to a vertical list. Therefore, Eplain provides \vpenalty and \hpenalty which first leave the other mode and then do \penalty.

More precisely, \vpenalty inserts \par if the current mode is horizontal, and \hpenalty inserts \leavevmode if the current mode is vertical. (Thus, \vpenalty cannot be used in math mode.)


7.10 Auxiliary files

It is common to write some information out to a file to be used on a subsequent run. But when it is time to read the file again, you only want to do so if the file actually exists. \testfileexistence is given an argument which is appended to \jobname, and sets the conditional \iffileexists appropriately. For example:

\testfileexistence{toc}%
\iffileexists
   \input \jobname.toc
\fi

\testfileexistence takes an optional parameter; when given, it will override \jobname for the root part of the file name. For example, if you want to test for the file answers.aux, you can do this with the following:

\testfileexistence[answers]{aux}%
\iffileexists
   \input answers.aux
\fi

7.11 User-defined environments

Plain TeX does not provide “named” block structures, only the anonymous \begingroup and \endgroup pair. The disadvantage of this is that when there are several such groups and one is mismatched, it can be difficult to find the error. Eplain provides a named block structure so that if you forget an \environment or an \endenvironment, you will (probably) get an error message about it.

For example:

\def\itpar{
  \environment{@italicpar}
  \it\par
}
\def\enditpar{
  \par
  \endenvironment{@italicpar}%
}

which could then be used to set italicized paragraphs:

\itpar
If I reprehend anything in this world, it is the use of my oracular
tongue, and a nice derangement of epitaphs! 
\enditpar

The above sort of environment allows nesting. But environments shouldn’t always be allowed to nest. Put the control sequence \checkenv at the beginning of a macro that is going to define an environment that should not be nested.


7.12 Page list and page range parsers

The macros which Eplain uses to parse the page lists and ranges in the index, \idxparselist and \idxparserange (see Page destinations for index terms), are sometimes useful when defining page number encapsulators. They take one argument, text to parse. When a page list (range) is not present, they set \idxpagei to be \empty; when a list (range) is detected, they set \idxpagei and \idxpageii to the first and the second page numbers, respectively.

Eplain’s defaults for the page list and page range delimiters are the same as those in MakeIndex, a comma followed by a space (‘, ’) and two dashes (‘--’), respectively. If you customize MakeIndex to use different delimiters, you must not forget to let Eplain know about them with the commands

\setidxpagelistdelimiter{list-delim}
\setidxpagerangedelimiter{page-delim}

These commands save the list-delim and page-delim delimiters in \idxpagelistdelimiter and \idxpagerangedelimiter, respectively.

For example, you may want to define a page number markup command which italicizes and properly underlines page ranges by underlining only the page numbers and not the delimiter:

\def\ituline#1{%
  {\it
  \idxparserange{#1}%
  \ifx\idxpagei\empty
    % The argument is a single page number.
    \underbar{#1}%
  \else
    % The argument is a page range.
    \underbar{\idxpagei}\idxpagerangedelimiter\underbar{\idxpageii}%
  \fi}%
}

Note that the \ituline macro is not aware of page lists. This is not needed if you use hyperlinks in the index, because \hlidx and \hlidxpage will break up the page lists before calling the user’s page encapsulator (see Page destinations for index terms), so \ituline will never see the lists. If, however, you need to design a macro which also takes care of the lists, you can extend \ituline with an additional call to \idxparselist.


8 Demo files

This chapter contains listings of source files, along with the output they produce (where appropriate), which illustrate various aspects of Eplain. The files can be found in the demo subdirectory of Eplain distribution. These demos, both the sources and the compiled PDF and PS files, are also available from https://tug.org/eplain/demo.


8.2 Highlighting TeX comments in listings (lscommnt.tex)

lscommnt
% (This file is public domain.)
% Demonstrate how Eplain can be used to include a TeX source file
% verbatim, typesetting comments in colored italic typewriter type.

% Load Eplain and LaTeX's color.sty package.
\input eplain
\beginpackages \usepackage{color} \endpackages
\nopagenumbers % Disable page numbers.
\font\commentfont = cmitt10 % Font for the comments (italic \tt).
% We'll define some `protected' macros with `@' in their names.
\makeatletter
% Define an equivalent of Eplain's \letreturn, to be able to assign
% various actions to the (active) percent character.
\begingroup \makeactive\%
  \gdef\letpercent{\let%}
\endgroup
% The listing hook to be called in \setuplistinghook, see below.  It
% makes `%' active and assigns it a `start comment' action.
\def\hlightcommentslisting{\makeactive\% \letpercent\start@comment}%
% This is what `%' is aliased to before a comment is started.
\def\start@comment{%
  \leavevmode % Needed in the very first line of the input to process
              % the new par (possibly inserting line number) before we
              % kick in with the color and stuff.
  \begingroup % Isolate color and font changes and the redefinitions.
    \commentfont
    \color[cmyk]{0.28,1,1,0.35}%
    \percentchar            % Produce the actual `%' and
    \letpercent\percentchar % make all following `%'s do the same.
    \letreturn\end@comment  % Call \end@comment at end-of-line.
}
% \end@comment (alias for ^^M inside a comment) will end the comment
% started by \start@comment.  We make ^^M active temporarily so that
% the active version of ^^M gets "frozen" into \end@comment.
\begingroup \makeactive\^^M % Avoid ^^M's from here on.
  \gdef\end@comment{\endgroup ^^M}%
\endgroup
\resetatcatcode % Make `@' again inaccessible for use in macro names.

% Define \setuplistinghook to setup comments highlighting, line
% numbering and omitting the last (empty) line of input.
\def\setuplistinghook{\hlightcommentslisting \linenumberedlisting
                      \nolastlinelisting}
% Isn't this fun?  This file typesets itself, with the extra bonus of
% the pretty-printed comments and numbered source lines!
\listing{lscommnt}
\bye

Macro index

Jump to:   @  
A   B   C   D   E   F   G   H   I   J   L   M   N   O   P   Q   R   S   T   U   V   W   X   Z  
Index EntrySection

@
@getoptionalargMacro arguments
@hllabelDestination types for hypertex
@hllabelLink types for hypertex
@hllabelDestination types for pdftex and dvipdfm
@hllabelLink types for pdftex and dvipdfm
@indexproof insertion classProofing index terms

A
abovecolumnskipMultiple columns
abovecolumnspenaltyTables
abovelistpenaltyFormatting lists
abovelistskipFormatting lists
abovelistskipamountFormatting lists
adjarrowArrows and morphisms
adjmapdownArrows and morphisms
adjmapleftArrows and morphisms
adjmaprightArrows and morphisms
adjmapupArrows and morphisms
advancebottommarginMargins
advanceleftmarginMargins
advancerightmarginMargins
advancetopmarginMargins
afterindextermCustomizing indexing
afterindexterm hookIndexing commands
AMSLaTeXLogos
AMSTeXLogos
arrowArrows and morphisms
arrowArrows and morphisms

B
bblemFormatting bibliographies
bblemphFormatting bibliographies
bblfilebasenameCitations
bblhookFormatting bibliographies
bblnewblockFormatting bibliographies
bblrmFormatting bibliographies
bblscFormatting bibliographies
bcolor (hyperlink option)Link options for pdftex and dvipdfm
bdash (hyperlink option)Link options for pdftex and dvipdfm
bdash (hyperlink option)Link options for pdftex and dvipdfm
begin for index entriesModifying index entries
begin{picture}Packages known to work
begin{theindex}Typesetting an index
beginindex hookTypesetting an index
beginlistFormatting lists
beginpackagesEnvironment for loading packages
belowcolumnskipMultiple columns
belowfootnoterulespaceFootnotes
belowlistskipFormatting lists
belowlistskipamountFormatting lists
biarrowArrows and morphisms
biblabelcontentsFormatting bibliographies
biblabelextraspaceFormatting bibliographies
biblabelpostcontentsFormatting bibliographies
biblabelprecontentsFormatting bibliographies
biblabelprintFormatting bibliographies
biblabelwidthFormatting bibliographies
bibliographyCitations
bibliography (hyperlinks)Citation hyperlinks
bibliographystyleCitations
BibTeXLogos
bihlineArrows and morphisms
bimapdownArrows and morphisms
bimapleftArrows and morphisms
bimaprightArrows and morphisms
bimapupArrows and morphisms
bislineArrows and morphisms
bivlineArrows and morphisms
blackboxBoxes
blanklineskipamount in justified textJustification
blanklineskipamount in obeyed textObeying spaces
bottom (destination option)Destination types for pdftex and dvipdfm
bottom (destination option)Destination options for pdftex and dvipdfm
bottommarginMargins
boxitBoxes
boxitspaceBoxes
bstyle (hyperlink option)Link options for pdftex and dvipdfm
bwidth (hyperlink option)Link options for pdftex and dvipdfm

C
catcodeCategory codes
centerJustification
centereddisplaysDisplays
channelwidthArrows and morphisms
channelwidthCommutative diagram parameters
citeCitations
cite (hyperlinks)Citation hyperlinks
cmd (destination option)Destination types for hypertex
cmd (destination option)Destination options for hypertex
cmd (destination option)Destination types for pdftex and dvipdfm
cmd (destination option)Destination options for pdftex and dvipdfm
cmd (hyperlink option)Link types for hypertex
cmd (hyperlink option)Link options for hypertex
cmd (hyperlink option)Link types for pdftex and dvipdfm
cmd (hyperlink option)Link options for pdftex and dvipdfm
color (hyperlink option)Options supported by all drivers
colormodel (hyperlink option)Options supported by all drivers
columnfillMultiple columns
commdiagConstruction of commutative diagrams
commdiagbaselinesConstruction of commutative diagrams
commdiagbaselinesCommutative diagram parameters
csn\csn and \ece

D
definecolorHyperlinks (xhyper.tex)
definecontentsfileAlternative contents files
defineindexIndexing
definexrefDefining generic references
definexrefHyperlinks (xhyper.tex)
definexref (hyperlinks)Cross-reference hyperlinks
depth (destination option)Destination types for pdftex and dvipdfm
depth (destination option)Destination options for pdftex and dvipdfm
depth (hyperlink option)Link options for pdftex and dvipdfm
discretionariesPaths
displaylinesDisplays
DOCVIEW pdfmarkMaking PDF outlines
dospecialsVerbatim listing
doublecolumnsMultiple columns
drawlineSlanted lines and vectors
drawvectorSlanted lines and vectors
dvipdfm (hyperlink driver)Hyperlink drivers pdftex and dvipdfm

E
eattokenMacro arguments
ece\csn and \ece
edefappend\edefappend
ehruleRules
emCommands from LaTeX
emphCommands from LaTeX
enablehyperlinksIntroduction to hyperlinks
enablehyperlinksChoosing destination placement
enablehyperlinksHyperlink driver nolinks
end for index entriesModifying index entries
end{picture}Packages known to work
end{theindex}Typesetting an index
endlistFormatting lists
endnumberedlistLists
endorderedlistLists
endpackagesEnvironment for loading packages
endunorderedlistLists
eplainInvoking Eplain
eplaininputEnvironment for loading packages
eqalignnoDisplays
eqalignnoDisplays
eqalignnumDisplays
eqconstructFormatting equation references
eqdefEquation references
eqdef (hyperlinks)Equation reference hyperlinks
eqdefnEquation references
eqdefn (hyperlinks)Equation reference hyperlinks
eqnoDisplays
eqnumDisplays
eqnumEquation references
eqnumEquation references
eqnumberEquation references
eqprintFormatting equation references
eqrefEquation references
eqrefEquation reference hyperlinks
eqrefnEquation references
eqrefnEquation reference hyperlinks
eqsubdefSubequation references
eqsubdef (hyperlinks)Equation reference hyperlinks
eqsubdefnSubequation references
eqsubdefn (hyperlinks)Equation reference hyperlinks
eqsubreftextSubequation references
eTeXLogos
everyfootnoteFootnotes
evruleRules
expandonce\expandonce
ext (hyperlink option)Link types for hypertex
ext (hyperlink option)Link options for hypertex
ExTeXLogos

F
file (hyperlink option)Link types for hypertex
file (hyperlink option)Link options for hypertex
file (hyperlink option)Link types for pdftex and dvipdfm
file (hyperlink option)Link types for pdftex and dvipdfm
file (hyperlink option)Link options for pdftex and dvipdfm
fileexists (conditional)Auxiliary files
filename (hyperlink type)Link types for hypertex
filename (hyperlink type)Link types for pdftex and dvipdfm
filepage (hyperlink type)Link types for pdftex and dvipdfm
fit (destination type)Destination types for pdftex and dvipdfm
fitb (destination type)Destination types for pdftex and dvipdfm
fitbh (destination type)Destination types for pdftex and dvipdfm
fitbv (destination type)Destination types for pdftex and dvipdfm
fith (destination type)Destination types for pdftex and dvipdfm
fitr (destination type)Destination types for pdftex and dvipdfm
fitv (destination type)Destination types for pdftex and dvipdfm
flushleftJustification
flushrightJustification
fmtversionIntroduction
footnote (hyperlinks)Footnote hyperlinks
footnotemarkseparationFootnotes
footnoteruleheightFootnotes
footnoterulewidthFootnotes
forIteration
ForIteration
fracFractions
fullmonthnameTime of day
futurenonspacelet\futurenonspacelet

G
getpropertyProperties
gloggingallDiagnostics
gobbleMacro arguments
gobbletwoMacro arguments
gridcommdiagConstruction of commutative diagrams
gtracingallDiagnostics
gutterMultiple columns
gutterboxMultiple columns

H
hangindent for index entriesTypesetting an index
harrowlengthArrows and morphisms
harrowlengthCommutative diagram parameters
hchannelCommutative diagram parameters
height (destination option)Destination types for pdftex and dvipdfm
height (destination option)Destination options for pdftex and dvipdfm
height (hyperlink option)Link options for pdftex and dvipdfm
hgridConstruction of commutative diagrams
hgridCommutative diagram parameters
hldestExplicit hyperlinks
hldestDestination types for hypertex
hldestDestination types for pdftex and dvipdfm
hldestSetting hyperlink types and options
hldestoffHyperlink driver nolinks
hldestoffTurning low-level commands on/off
hldestonTurning low-level commands on/off
hldestoptsSetting default types and options
hldestoptsSetting group options
hldestoptsHyperlinks (xhyper.tex)
hldesttypeSetting default types and options
hldesttypeSetting group types
hldesttypeHyperlinks (xhyper.tex)
hlendExplicit hyperlinks
hlendHyperlinks (xhyper.tex)
hlfootbacklabelFootnote hyperlinks
hlfootlabelFootnote hyperlinks
hlfootlabelnumberFootnote hyperlinks
hlhashLink types for hypertex
hlidxExact destinations for index terms
hlidxlabelExact destinations for index terms
hlidxlabelnumberExact destinations for index terms
hlidxpagePage destinations for index terms
hlidxpagelabelPage destinations for index terms
hlight (hyperlink option)Link options for pdftex and dvipdfm
hlightcommentslistingHighlighting TeX comments in listings (lscommnt.tex)
hlineArrows and morphisms
hloffHyperlink driver nolinks
hloffTurning low-level commands on/off
hlonTurning low-level commands on/off
hloptsSetting default types and options
hloptsSetting group options
hloptsHyperlinks (xhyper.tex)
hlstartExplicit hyperlinks
hlstartLink types for hypertex
hlstartLink types for pdftex and dvipdfm
hlstartSetting hyperlink types and options
hlstartHyperlinks (xhyper.tex)
hltypeSetting default types and options
hltypeSetting group types
hmorphposnArrows and morphisms
hmorphposnCommutative diagram parameters
hmorphposndnArrows and morphisms
hmorphposndnCommutative diagram parameters
hmorphposnlftArrows and morphisms
hmorphposnlftCommutative diagram parameters
hmorphposnrtArrows and morphisms
hmorphposnrtCommutative diagram parameters
hmorphposnupArrows and morphisms
hmorphposnupCommutative diagram parameters
hoffsetProofing index terms
hookactionHooks
hookactiononceHooks
hookappendHooks
hookprependHooks
hookrunHooks
hrefGeneral hyperlinks
hruledefaultdepthRules
hruledefaultheightRules
hsizeMargins
hypertex (hyperlink driver)Hyperlink driver hypertex
hyphenpenalty for index entriesTypesetting an index

I
identityMacro arguments
idxIndexing commands
idx (hyperlinks)Index hyperlinks
idxargcloseIndex entries with special characters
idxargopenIndex entries with special characters
idxbeginrangemarkCustomizing indexing
idxencapoperatorCustomizing indexing
idxendrangemarkCustomizing indexing
idxexactChoosing destination placement
idxmarkedIndexing commands
idxmarked (hyperlinks)Index hyperlinks
idxnameIndexing commands
idxname (hyperlinks)Index hyperlinks
idxnameseparatorIndexing commands
idxnoneChoosing destination placement
idxpageChoosing destination placement
idxpageiPage list and page range parsers
idxpageiiPage list and page range parsers
idxpagelistdelimiterPage list and page range parsers
idxpagenumCustomizing indexing
idxpagerangedelimiterPage list and page range parsers
idxpagerangedelimiterPage list and page range parsers
idxparselistPage list and page range parsers
idxparserangePage list and page range parsers
idxrangebeginwordCustomizing indexing
idxrangeendwordCustomizing indexing
idxseealsocmdwordCustomizing indexing
idxseecmdwordCustomizing indexing
idxsubentryseparatorCustomizing indexing
idxsubmarkedIndexing commands
idxsubmarked (hyperlinks)Index hyperlinks
ifempty\ifempty
iffileexistsAuxiliary files
ifidxIndexing
ifindexproofingProofing index terms
ifinteger\ifinteger and \isinteger
ifpdfChecking for PDF output
ifpdfIntroduction to hyperlinks
ifpdfMaking PDF outlines
ifrewritetocfileReading the .toc file
ifundefined\ifundefined
includegraphicsHyperlinks (xhyper.tex)
indexfilebasenameTypesetting an index
indexfontsTypesetting an index
indexitem hookTypesetting an index
indexprooffontProofing index terms
indexproofingfalseProofing index terms
indexproofingtrueProofing index terms
indexprooftermProofing index terms
indexproofunboxProofing index terms
indexseeCustomizing indexing
indexseeHyperlinks in see and see also entries
indexseealsoCustomizing indexing
indexseealsoHyperlinks in see and see also entries
indexseealsowordsCustomizing indexing
indexseewordCustomizing indexing
indexsetmarginsProofing index terms
indexspaceTypesetting an index
innerdefAllocation macros
innerinnerdefAllocation macros
innernewboxAllocation macros
innernewcountAllocation macros
innernewdimenAllocation macros
innernewfamAllocation macros
innernewhelpAllocation macros
innernewifAllocation macros
innernewinsertAllocation macros
innernewlanguageAllocation macros
innernewreadAllocation macros
innernewskipAllocation macros
innernewtoksAllocation macros
innernewwriteAllocation macros
inputEnvironment for loading packages
insidemarginProofing index terms
interfootnoteskipFootnotes
interitemskipFormatting lists
interitemskipamountFormatting lists
isinteger\ifinteger and \isinteger
item in indexesTypesetting an index
itemletterFormatting lists
itemnumberFormatting lists
itulinePage list and page range parsers

J
jobnameCitations
jobnameTypesetting an index
jobnameAuxiliary files

L
LAMSTeXLogos
LaTeXLogos
lbracecharCategory codes
left (destination option)Destination types for pdftex and dvipdfm
left (destination option)Destination types for pdftex and dvipdfm
left (destination option)Destination types for pdftex and dvipdfm
left (destination option)Destination types for pdftex and dvipdfm
left (destination option)Destination options for pdftex and dvipdfm
leftdisplayindentDisplays
leftdisplaysDisplays
leftdisplaysetupFormatting displays
lefteqnumbersDisplays
leftmarginMargins
leftskipJustification
leqalignnoDisplays
leqalignnoDisplays
leqnoDisplays
letreturnCategory codes
letterCategory codes
lftArrows and morphisms
liLists
li (hyperlinks)List hyperlinks
linenumberedlistingVerbatim listing
linenumberedlistingHighlighting TeX comments in listings (lscommnt.tex)
listcompactLists
listingVerbatim listing
listingHighlighting TeX comments in listings (lscommnt.tex)
listingfontVerbatim listing
listleftindentFormatting lists
listmarkerspaceFormatting lists
listrightindentFormatting lists
loggingallDiagnostics
loopIteration

M
makeactiveCategory codes
makeatletterCategory codes
makeatotherCategory codes
makeblankboxBoxes
makecolumnsTables
makeheadlineProofing index terms
mapdownArrows and morphisms
mapdownArrows and morphisms
mapleftArrows and morphisms
mapleftArrows and morphisms
maprightArrows and morphisms
maprightArrows and morphisms
mapupArrows and morphisms
mapupArrows and morphisms
matrixConstruction of commutative diagrams
mboxCommands from LaTeX
MFLogos
monthnameTime of day
morphdistArrows and morphisms
morphdistCommutative diagram parameters

N
name (hyperlink type)Link types for hypertex
name (hyperlink type)Link types for pdftex and dvipdfm
new…Allocation macros
newblockCommands from LaTeX
newcommandCommands from LaTeX
newwin (hyperlink option)Link types for pdftex and dvipdfm
newwin (hyperlink option)Link types for pdftex and dvipdfm
newwin (hyperlink option)Link options for pdftex and dvipdfm
noarrowInvoking Eplain
noauxfileInvoking Eplain
nobibtexInvoking Eplain
nociteCitations
nolastlinelistingVerbatim listing
nolastlinelistingHighlighting TeX comments in listings (lscommnt.tex)
nolinks (hyperlink driver)Hyperlink driver nolinks
normalbaselineskipOptions supported by all drivers
num (hyperlink type)Link types for pdftex and dvipdfm
numberedfootnoteFootnotes
numberedfootnote (hyperlinks)Footnote hyperlinks
numberedlistLists
numberedlistdepthFormatting lists
numberedmarkerFormatting lists
numbernameWriting out numbers

O
obeywhitespaceObeying spaces
orderedlistLists
otherCategory codes
outerAllocation macros
outsidemarginProofing index terms

P
page (hyperlink type)Link types for pdftex and dvipdfm
pagefit (hyperlink option)Link types for pdftex and dvipdfm
pagefit (hyperlink option)Link types for pdftex and dvipdfm
pagefit (hyperlink option)Link types for pdftex and dvipdfm
pagefit (hyperlink option)Link options for pdftex and dvipdfm
pagenoProofing index terms
pagetotalMultiple columns
paperheightMargins
paperwidthMargins
parfillskip, reset by \ragged...Justification
parindent in indexesTypesetting an index
pathPaths
pdfescapestring pdfTeX primitiveMaking PDF outlines
pdfmark (PDF language primitive)Making PDF outlines
pdfoutline (pdftex primitive)Making PDF outlines
pdftex (hyperlink driver)Hyperlink drivers pdftex and dvipdfm
percentcharCategory codes
phantomeqlabelEquation reference hyperlinks
phantomeqnumberEquation reference hyperlinks
previouseverydisplayFormatting displays
printbetweencitationsFormatting citations
printcitefinishFormatting citations
printcitenoteFormatting citations
printcitestartFormatting citations
printitemFormatting lists
printlistinglinenoVerbatim listing
printlistinglinenoVerbatim listing
providecommandCommands from LaTeX

Q
quadcolumnsMultiple columns

R
raggedleftJustification
raggedleftskipJustification
raggedrightJustification
raggedright for index entriesTypesetting an index
raise (hyperlink option)Options supported by all drivers
raise (hyperlink option)Setting group options
raw (destination type)Destination types for hypertex
raw (destination type)Destination types for pdftex and dvipdfm
raw (hyperlink type)Link types for hypertex
raw (hyperlink type)Link types for pdftex and dvipdfm
rbracecharCategory codes
readindexfileTypesetting an index
readindexfile (hyperlinks)Index hyperlinks
readtocfileReading the .toc file
refUsing generic references
refHyperlinks (xhyper.tex)
ref (hyperlinks)Cross-reference hyperlinks
refnUsing generic references
refn (hyperlinks)Cross-reference hyperlinks
refsUsing generic references
refs (hyperlinks)Cross-reference hyperlinks
refspaceCross-reference hyperlinks
refspacePage reference hyperlinks
reftieCross-reference hyperlinks
reftieCross-reference hyperlinks
reftieEquation reference hyperlinks
renewcommandCommands from LaTeX
repeatIteration
resetatcatcodeEnvironment for loading packages
resetatcatcodeCategory codes
rewritetocfile (conditional)Reading the .toc file
right (destination option)Destination types for pdftex and dvipdfm
right (destination option)Destination options for pdftex and dvipdfm
righteqnumbersDisplays
rightmarginMargins
rotateboxHyperlinks (xhyper.tex)
rtArrows and morphisms

S
sanitizeConverting to characters
sarrowlengthArrows and morphisms
sarrowlengthCommutative diagram parameters
scCommands from LaTeX
see for index entriesModifying index entries
see for index entriesCustomizing indexing
seealso for index entriesModifying index entries
seevariantCustomizing indexing
setidxpagelistdelimiterPage list and page range parsers
setidxpagerangedelimiterPage list and page range parsers
setpropertyProperties
setuplistinghookVerbatim listing
setuplistinghookHighlighting TeX comments in listings (lscommnt.tex)
sidxIndexing commands
sidxmarkedIndexing commands
sidxnameIndexing commands
sidxsubmarkedIndexing commands
singlecolumnMultiple columns
slineArrows and morphisms
slineArrows and morphisms
SLiTeXLogos
spaceskip, reset by \ragged...Justification
specialIntroduction to hyperlinks
special ps: for dvipsMaking PDF outlines
specialpathdelimiters (conditional)Paths
subeqnumberSubequation references
subitem in indexesTypesetting an index
subsubitem in indexesTypesetting an index

T
testfileexistenceAuxiliary files
TeXLogos
textbfCommands from LaTeX
timestampTime of day
timestringTime of day
toc…entryWriting the .toc file
toc…entryWriting the .toc file
tocfilebasenameChanging the .toc file's root name
todayTime of day
top (destination option)Destination types for pdftex and dvipdfm
top (destination option)Destination types for pdftex and dvipdfm
top (destination option)Destination types for pdftex and dvipdfm
top (destination option)Destination types for pdftex and dvipdfm
top (destination option)Destination options for pdftex and dvipdfm
topmarginMargins
tracingallDiagnostics
tracingboxesDiagnostics
tracingoffDiagnostics
triplecolumnsMultiple columns
ttPackages known to work
ttfamilyPackages known to work

U
uncatcodespecialsVerbatim listing
uncatcodespecialsCategory codes
unorderedlistLists
unorderedlistdepthFormatting lists
unorderedmarkerFormatting lists
urlHyperlinks (xhyper.tex)
url (hyperlink type)Link types for hypertex
url (hyperlink type)Link types for pdftex and dvipdfm
url (hyperlinks)URL hyperlinks
usepackageThe \usepackage command

V
varrowlengthArrows and morphisms
varrowlengthCommutative diagram parameters
vchannelCommutative diagram parameters
verbatimVerbatim listing
verbatimescapecharVerbatim listing
vgridConstruction of commutative diagrams
vgridCommutative diagram parameters
vlineArrows and morphisms
vmorphposnArrows and morphisms
vmorphposnCommutative diagram parameters
vmorphposndnArrows and morphisms
vmorphposndnCommutative diagram parameters
vmorphposnlftArrows and morphisms
vmorphposnlftCommutative diagram parameters
vmorphposnrtArrows and morphisms
vmorphposnrtCommutative diagram parameters
vmorphposnupArrows and morphisms
vmorphposnupCommutative diagram parameters
vpenaltyMode-specific penalties
vruledefaultwidthRules

W
width (destination option)Destination types for pdftex and dvipdfm
width (destination option)Destination options for pdftex and dvipdfm
width (hyperlink option)Link options for pdftex and dvipdfm
writenumberedtocentryWriting the .toc file
writenumberedtoclineWriting the .toc file
writetocentryWriting the .toc file

X
XeLaTeXLogos
XeTeXLogos
xrdefPage references
xrdef (hyperlinks)Page reference hyperlinks
xrefPage references
xref (hyperlinks)Page reference hyperlinks
xrefnUsing generic references
xrefn (hyperlinks)Cross-reference hyperlinks
xrefpagewordPage references
xrefpagewordPage reference hyperlinks
xrefwarning conditionalUsing generic references
xrefwarningfalseCitations
xrlabelConverting to characters
xspaceskip, reset by \ragged...Justification
xyz (destination type)Destination types for hypertex
xyz (destination type)Destination types for pdftex and dvipdfm

Z
zoom (destination option)Destination types for pdftex and dvipdfm
zoom (destination option)Destination options for pdftex and dvipdfm


Concept index

Jump to:   .   *  
A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Z  
Index EntrySection

.
.aux fileCitations
.aux fileCross-references
.bbl fileCitations
.bib fileCitations
.bst filesCitations
.cls filesLoading LaTeX packages
.eps filesPackages known to work
.eps filesPackages known to work
.fmt fileInstallation
.fmt fileInvoking Eplain
.idx filesIndexing
.idx filesIndex hyperlinks
.ind filesIndexing
.ind filesIndex hyperlinks
.pdf filesChecking for PDF output
.pdf filesPackages known to work
.pdf filesIntroduction to hyperlinks
.ps filesIntroduction to hyperlinks
.sty filesLoading LaTeX packages
.toc fileContents

*
*-form of LaTeX commandsCommands from LaTeX

A
active charactersCategory codes
after index termsCustomizing indexing
alignmentsTables
all groups, specifyingSetting group types
allocation macrosAllocation macros
alphanumeric referencesCitations
AMSLaTeXLogos
amsppt.styInvoking Eplain
AMSTeXLogos
AMSTeX conflictsInvoking Eplain
arguments, ignoringMacro arguments
arrowsArrows and morphisms
atomProperties
autopict.styPackages known to work
auxiliary files, existence ofAuxiliary files
avoiding boxed linksURL hyperlinks
avoiding boxed linksSetting default types and options

B
backslash characterCategory codes
balancing of columns with \singlecolumnMultiple columns
Berry, KarlIntroduction
beveled hyperlink borderLink options for pdftex and dvipdfm
bibliographiesCitations
bibliography fontsFormatting bibliographies
bibliography items, extra space betweenFormatting bibliographies
bibliography, formatting theFormatting bibliographies
bibliography, hyperlinksCitation hyperlinks
bibtexInvoking Eplain
BibTeXCitations
BibTeXLogos
black boxesBoxes
bookmarks, making PDFMaking PDF outlines
Borceux, FrancisConstruction of commutative diagrams
border color, hyperlinkLink options for pdftex and dvipdfm
border style, hyperlinkLink options for pdftex and dvipdfm
border style, hyperlinkLink options for pdftex and dvipdfm
border width, hyperlinkLink options for pdftex and dvipdfm
Bott, RaoulConstruction of commutative diagrams
boxed links, avoidingURL hyperlinks
boxed links, avoidingSetting default types and options
boxes, openBoxes
braces, inside index entriesIndex entries with special characters
brackets, inside index entriesIndex entries with special characters
Brockett, Roger W.Construction of commutative diagrams
Butterfly LemmaConstruction of commutative diagrams

C
Carlisle, DavidLoading LaTeX packages
catcode of ‘@Environment for loading packages
category codesCategory codes
centeringJustification
characters, converting toConverting to characters
characters, specialVerbatim listing
citationsCitations
citations, formattingFormatting citations
citations, hyperlinksCitation hyperlinks
citations, undefinedCitations
cmtt8Proofing index terms
colorPackages known to work
color, demoHyperlinks (xhyper.tex)
color, hyperlink borderLink options for pdftex and dvipdfm
color, hyperlinksURL hyperlinks
color, hyperlinksOptions supported by all drivers
color, hyperlinksSetting default types and options
color, problems with pdfTeXPackages known to work
color.styPackages known to work
color.styURL hyperlinks
color.styHyperlink driver nolinks
color.stySetting default types and options
color.styHyperlinks (xhyper.tex)
colored linksURL hyperlinks
colored linksOptions supported by all drivers
colored linksSetting default types and options
column balancing with \singlecolumnMultiple columns
column ejectMultiple columns
commas after index termsCustomizing indexing
commas in cross-referencing index entriesCustomizing indexing
comments, highlighting in listingsHighlighting TeX comments in listings (lscommnt.tex)
commutative diagramsCommutative diagrams
contentsContents
contents, and verbatim textWriting the .toc file
contents, hyperlinksContents hyperlinks
contents, shortReading the .toc file
ConTeXtPackages known to work
continued index entriesTypesetting an index
covering homotopy propertyConstruction of commutative diagrams
cross-referencesCross-references
cross-references, defining generalDefining generic references
cross-references, defining generalUsing generic references
cross-references, demoHyperlinks (xhyper.tex)
cross-references, hyperlinksCross-reference hyperlinks
cross-referencing index entriesModifying index entries
cross-referencing index entriesCustomizing indexing
CTRL-L, and verbatim listingVerbatim listing
cubeConstruction of commutative diagrams
customizing indexingCustomizing indexing

D
dashed hyperlink borderLink options for pdftex and dvipdfm
dashed hyperlink borderLink options for pdftex and dvipdfm
dateTime of day
default hyperlink optionsSetting hyperlink types and options
default hyperlink optionsSetting group types
default hyperlink typeSetting hyperlink types and options
default hyperlink typeSetting group types
defining general referencesDefining generic references
defining general referencesUsing generic references
definitions, globalCategory codes
demo filesDemo files
destgroupImplicit hyperlinks
destgroup ‘bib’Citation hyperlinks
destgroup ‘definexref’Cross-reference hyperlinks
destgroup ‘eq’Equation reference hyperlinks
destgroup ‘foot’Footnote hyperlinks
destgroup ‘footback’Footnote hyperlinks
destgroup ‘idx’Index hyperlinks
destgroup ‘li’List hyperlinks
destgroup ‘xrdef’Page reference hyperlinks
destgroup optionsSetting hyperlink types and options
destgroup optionsSetting group options
destgroup options, demoHyperlinks (xhyper.tex)
destgroup typeSetting hyperlink types and options
destgroup typeSetting group types
destgroup type, demoHyperlinks (xhyper.tex)
destination groupImplicit hyperlinks
destination optionsIntroduction to hyperlinks
destination options, commonOptions supported by all drivers
destination options, dvipdfmDestination options for pdftex and dvipdfm
destination options, hypertexDestination options for hypertex
destination options, pdftexDestination options for pdftex and dvipdfm
destination typeIntroduction to hyperlinks
destination types, dvipdfmDestination types for pdftex and dvipdfm
destination types, hypertexDestination types for hypertex
destination types, pdftexDestination types for pdftex and dvipdfm
destinations, default optionsSetting hyperlink types and options
destinations, default optionsSetting group types
destinations, default typeSetting hyperlink types and options
destinations, default typeSetting group types
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, dimensionsDestination options for pdftex and dvipdfm
destinations, disablingHyperlink driver nolinks
destinations, disablingTurning hyperlinks on/off
destinations, group optionsSetting hyperlink types and options
destinations, group optionsSetting group options
destinations, group options, demoHyperlinks (xhyper.tex)
destinations, group typeSetting hyperlink types and options
destinations, group typeSetting group types
destinations, group type, demoHyperlinks (xhyper.tex)
destinations, in another fileLink types for hypertex
destinations, in another fileLink types for pdftex and dvipdfm
destinations, in another fileLink types for pdftex and dvipdfm
destinations, large operatorsOptions supported by all drivers
destinations, large operatorsSetting group options
destinations, magnificationDestination options for pdftex and dvipdfm
destinations, namedLink types for hypertex
destinations, namedLink types for pdftex and dvipdfm
destinations, numberedLink types for pdftex and dvipdfm
destinations, pageLink types for pdftex and dvipdfm
destinations, raisingOptions supported by all drivers
destinations, urlLink types for hypertex
destinations, urlLink types for pdftex and dvipdfm
detecting numbers\ifinteger and \isinteger
diagnosticsDiagnostics
Diagram, macros for LaTeXConstruction of commutative diagrams
dimensions, hyperlinkLink options for pdftex and dvipdfm
dimensions, hyperlinkLink options for pdftex and dvipdfm
dimensions, hyperlinkLink options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
dimensions, hyperlink destinationDestination options for pdftex and dvipdfm
disabling hyperlinksHyperlink driver nolinks
disabling hyperlinksTurning hyperlinks on/off
disabling indexesIndexing
displayed math and hyperlinksOptions supported by all drivers
displayed math and hyperlinksSetting group options
displays, left-justifyingDisplays
do…while loopsIteration
double column outputMultiple columns
double columns in indexesTypesetting an index
draft, option for graphics.styPackages known to work
driver dvipdfmHyperlink drivers pdftex and dvipdfm
driver hypertexHyperlink driver hypertex
driver nolinksHyperlink driver nolinks
driver pdftexHyperlink drivers pdftex and dvipdfm
drivers, hyperlinkIntroduction to hyperlinks
dvipdfmIntroduction to hyperlinks
dvipdfmHyperlink driver hypertex
dvipdfmHyperlink driver hypertex
dvipdfm, destination optionsDestination options for pdftex and dvipdfm
dvipdfm, destination typesDestination types for pdftex and dvipdfm
dvipdfm, hyperlink driverHyperlink drivers pdftex and dvipdfm
dvipdfm, link optionsLink options for pdftex and dvipdfm
dvipdfm, link typesLink types for pdftex and dvipdfm
dvipsHyperlink driver hypertex
dvipsHyperlink driver hypertex
dvips, making PDF outlines forMaking PDF outlines

E
Eijkhout, VictorIteration
eject in multicolumnsMultiple columns
electronic mail addresses, breakingPaths
electronic mail addresses, breakingPackages known to work
empty argument, checking for\ifempty
empty equation labelsEquation references
empty equation labels, referring toEquation references
empty string, checking for\ifempty
Encapsulated PostScriptPackages known to work
Encapsulated PostScriptPackages known to work
engines, testing forChecking for PDF output
environments, user-definedUser-defined environments
Eplain, installingInstallation
Eplain, invokingInvoking Eplain
Eplain, purpose ofIntroduction
Eplain, upgradingInstallation
eplain.auxInstallation
eplain.fmtInstallation
EPSPackages known to work
EPSPackages known to work
epstopdfPackages known to work
epstopdf.styPackages known to work
equation labels, characters valid inEquation references
equation numbers, formatting ofFormatting equation references
equation numbers, left-alignmentDisplays
equations, giving numbers to allEquation references
equations, groups ofSubequation references
equations, hyperlinksEquation reference hyperlinks
equations, numberingEquation references
equations, references toEquation references
error messagesDiagnostics
error on \inputEnvironment for loading packages
escape character, changing verbatimVerbatim listing
eTeXLogos
exact index hyperlinksExact destinations for index terms
expansion, one-level\expandonce
explicit hyperlinksExplicit hyperlinks
explicit hyperlinks, demoHyperlinks (xhyper.tex)
ExTeXLogos

F
file, hyperlink toLink types for hypertex
file, hyperlink toLink types for pdftex and dvipdfm
file, hyperlink toLink types for pdftex and dvipdfm
file:’ linksGeneral hyperlinks
filenames, breakingPaths
filenames, breakingPackages known to work
files, verbatim listing ofVerbatim listing
files, verbatim listing of, demoHighlighting TeX comments in listings (lscommnt.tex)
filtering index entries with hyperlinksExact destinations for index terms
footnotes, hyperlinksFootnote hyperlinks
footnotes, numberedFootnotes
for loopsIteration
form feed character, and verbatim listingVerbatim listing
format fileInstallation
formatting index entriesTypesetting an index
fractionsFractions

G
GhostscriptHyperlink driver hypertex
GhostscriptHyperlink driver hypertex
gobbling argumentsMacro arguments
golden meanConstruction of commutative diagrams
golden meanConstruction of commutative diagrams
Graham, Ronald L.Citations
graphics collection, LaTeXLoading LaTeX packages
graphics collection, LaTeXPackages known to work
graphics collection, LaTeXHyperlink driver nolinks
graphics collection, LaTeX, demoHyperlinks (xhyper.tex)
graphics, omitting typesetting ofPackages known to work
graphics, problems with pdfTeXPackages known to work
graphics.styPackages known to work
graphicx.styPackages known to work
graphicx.styHyperlinks (xhyper.tex)
gridConstruction of commutative diagrams
group ‘’ (empty)Setting group types
group ‘*’Setting group types
group ‘bib’Citation hyperlinks
group ‘cite’Citation hyperlinks
group ‘definexref’Cross-reference hyperlinks
group ‘eq’Equation reference hyperlinks
group ‘eq’Equation reference hyperlinks
group ‘eq’Setting group options
group ‘foot’Footnote hyperlinks
group ‘footback’Footnote hyperlinks
group ‘hrefext’General hyperlinks
group ‘hrefint’General hyperlinks
group ‘idx’Index hyperlinks
group ‘li’List hyperlinks
group ‘ref’Cross-reference hyperlinks
group ‘url’URL hyperlinks
group ‘xrdef’Page reference hyperlinks
group ‘xref’Page reference hyperlinks
group option listSetting group options
group options, hyperlinkSetting hyperlink types and options
group options, hyperlinkSetting group options
group options, hyperlink, demoHyperlinks (xhyper.tex)
group type, hyperlinkSetting hyperlink types and options
group type, hyperlinkSetting group types
group type, hyperlink, demoHyperlinks (xhyper.tex)
group, destinationImplicit hyperlinks
group, disabling hyperlinksTurning hyperlinks on/off for a group
group, linkImplicit hyperlinks
group, preserving option listSetting group options
groups, specifying allSetting group types

H
hanging on \inputEnvironment for loading packages
help messagesDiagnostics
highlight modes, hyperlinkLink options for pdftex and dvipdfm
highlightingPackages known to work
highlighting, in listingsHighlighting TeX comments in listings (lscommnt.tex)
hooksHooks
Höppner, KlausPackages known to work
hyperlink border colorLink options for pdftex and dvipdfm
hyperlink colorURL hyperlinks
hyperlink colorOptions supported by all drivers
hyperlink colorSetting default types and options
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, dimensionsDestination options for pdftex and dvipdfm
hyperlink destination, magnificationDestination options for pdftex and dvipdfm
hyperlink destination, namedLink types for hypertex
hyperlink destination, namedLink types for pdftex and dvipdfm
hyperlink destination, numberedLink types for pdftex and dvipdfm
hyperlink destination, pageLink types for pdftex and dvipdfm
hyperlink destination, raisingOptions supported by all drivers
hyperlink dimensionsLink options for pdftex and dvipdfm
hyperlink dimensionsLink options for pdftex and dvipdfm
hyperlink dimensionsLink options for pdftex and dvipdfm
hyperlink driver dvipdfmHyperlink drivers pdftex and dvipdfm
hyperlink driver hypertexHyperlink driver hypertex
hyperlink driver nolinksHyperlink driver nolinks
hyperlink driver pdftexHyperlink drivers pdftex and dvipdfm
hyperlink driversIntroduction to hyperlinks
hyperlink group, disabling hyperlinksTurning hyperlinks on/off for a group
hyperlink group, preserving option listSetting group options
hyperlink options, commonOptions supported by all drivers
hyperlinks, bibliographyCitation hyperlinks
hyperlinks, border styleLink options for pdftex and dvipdfm
hyperlinks, border styleLink options for pdftex and dvipdfm
hyperlinks, border widthLink options for pdftex and dvipdfm
hyperlinks, citationsCitation hyperlinks
hyperlinks, cross-referencesCross-reference hyperlinks
hyperlinks, default optionsSetting hyperlink types and options
hyperlinks, default optionsSetting group types
hyperlinks, default typeSetting hyperlink types and options
hyperlinks, default typeSetting group types
hyperlinks, demoHyperlinks (xhyper.tex)
hyperlinks, disablingHyperlink driver nolinks
hyperlinks, disablingTurning hyperlinks on/off
hyperlinks, equationsEquation reference hyperlinks
hyperlinks, explicitExplicit hyperlinks
hyperlinks, explicit, demoHyperlinks (xhyper.tex)
hyperlinks, filtering index entriesExact destinations for index terms
hyperlinks, footnotesFootnote hyperlinks
hyperlinks, group option listSetting group options
hyperlinks, group optionsSetting hyperlink types and options
hyperlinks, group optionsSetting group options
hyperlinks, group options, demoHyperlinks (xhyper.tex)
hyperlinks, group typeSetting hyperlink types and options
hyperlinks, group typeSetting group types
hyperlinks, highlight modeLink options for pdftex and dvipdfm
hyperlinks, implicitImplicit hyperlinks
hyperlinks, implicit, demoHyperlinks (xhyper.tex)
hyperlinks, indexIndex hyperlinks
hyperlinks, index destination placementChoosing destination placement
hyperlinks, index, exactExact destinations for index terms
hyperlinks, large operatorsOptions supported by all drivers
hyperlinks, large operatorsSetting group options
hyperlinks, listsList hyperlinks
hyperlinks, opening in a new windowLink options for pdftex and dvipdfm
hyperlinks, page referencesPage reference hyperlinks
hyperlinks, preserving page-breakingHyperlink driver nolinks
hyperlinks, preserving spacingHyperlink driver nolinks
hyperlinks, see and see also index entriesHyperlinks in see and see also entries
hyperlinks, table of contentsContents hyperlinks
hyperlinks, to another fileLink types for hypertex
hyperlinks, to another fileLink types for pdftex and dvipdfm
hyperlinks, to another fileLink types for pdftex and dvipdfm
hyperlinks, urlGeneral hyperlinks
hyperlinks, urlURL hyperlinks
hyperlinks, urlLink types for hypertex
hyperlinks, urlLink types for pdftex and dvipdfm
hyperref.styPackages known not to work
hypertex, destination optionsDestination options for hypertex
hypertex, destination typesDestination types for hypertex
hypertex, hyperlink driverHyperlink driver hypertex
hypertex, link optionsLink options for hypertex
hypertex, link typesLink types for hypertex
hypertext linksHyperlinks

I
identifying numbers\ifinteger and \isinteger
idxuniqExact destinations for index terms
iftex.styChecking for PDF output
ignoring argumentsMacro arguments
implicit hyperlinksImplicit hyperlinks
implicit hyperlinks, demoHyperlinks (xhyper.tex)
inaccessible macrosCategory codes
index entries and rangesModifying index entries
index entries containing bracesIndex entries with special characters
index entries containing bracketsIndex entries with special characters
index entries with special charactersIndex entries with special characters
index entries, and cross-referencingModifying index entries
index entries, and cross-referencingCustomizing indexing
index entries, proofingProofing index terms
index entries, with verbatim textIndex entries with special characters
index entries’ page numbers, modifyingModifying index entries
index entry continuationsTypesetting an index
index entry formattingTypesetting an index
index entry general sortingIndexing commands
index fontsTypesetting an index
index groupingsTypesetting an index
index hyperlinkIndex hyperlinks
index typesettingTypesetting an index
index, and verbatim textIndex entries with special characters
index, choosing destination placementChoosing destination placement
index, destination placementChoosing destination placement
index, exact hyperlinksExact destinations for index terms
index, hyperlinks in see and see also entriesHyperlinks in see and see also entries
index, parsing page numbersPage destinations for index terms
index, placement of destinationsChoosing destination placement
index, selecting destination placementChoosing destination placement
index, underlining page numbersPage list and page range parsers
indexes, disablingIndexing
indexes, multipleIndexing
indexingIndexing
indexing and trailing spacesIndexing terms
indexing commandsIndexing commands
indexing termsIndexing terms
insertion classesMultiple columns
inset hyperlink borderLink options for pdftex and dvipdfm
installationInstallation
integers, detecting\ifinteger and \isinteger
italic correctionFormatting bibliographies
item labels, changingFormatting lists
iterationIteration

J
justificationJustification

K
Knuth, Donald ErvinCitations
Knuth, Donald ErvinCategory codes

L
labels on items, changingFormatting lists
labels, characters valid inCross-references
labels, empty equationEquation references
labels, empty equation, referring toEquation references
Lamport, LeslieIntroduction
LAMSTeXLogos
Lang, SergeArrows and morphisms
Lang, SergeConstruction of commutative diagrams
large operators and hyperlinksOptions supported by all drivers
large operators and hyperlinksSetting group options
LaTeXIntroduction
LaTeXCitations
LaTeXLogos
LaTeXSlanted lines and vectors
LaTeX commands, in btxmac.texCommands from LaTeX
LaTeX graphics collectionLoading LaTeX packages
LaTeX graphics collectionPackages known to work
LaTeX graphics collectionHyperlink driver nolinks
LaTeX graphics collection, demoHyperlinks (xhyper.tex)
LaTeX packagesLoading LaTeX packages
LaTeX packagesPackages known to work
LaTeX packagesPackages known not to work
LaTeX packages, restoring \inputEnvironment for loading packages
left-alignment of equation numbersDisplays
left-justificationJustification
left-justification of displaysDisplays
letterspacingPackages known to work
linear systems theoryConstruction of commutative diagrams
linesSlanted lines and vectors
link groupImplicit hyperlinks
link optionsIntroduction to hyperlinks
link options, commonOptions supported by all drivers
link options, dvipdfmLink options for pdftex and dvipdfm
link options, hypertexLink options for hypertex
link options, pdftexLink options for pdftex and dvipdfm
link typeIntroduction to hyperlinks
link types, dvipdfmLink types for pdftex and dvipdfm
link types, hypertexLink types for hypertex
link types, pdftexLink types for pdftex and dvipdfm
link, group optionsSetting hyperlink types and options
link, group optionsSetting group options
link, group options, demoHyperlinks (xhyper.tex)
link, group typeSetting hyperlink types and options
link, group typeSetting group types
linkgroupImplicit hyperlinks
linkgroup ‘cite’Citation hyperlinks
linkgroup ‘eq’Equation reference hyperlinks
linkgroup ‘eq’Setting group options
linkgroup ‘foot’Footnote hyperlinks
linkgroup ‘footback’Footnote hyperlinks
linkgroup ‘hrefext’General hyperlinks
linkgroup ‘hrefint’General hyperlinks
linkgroup ‘idx’Index hyperlinks
linkgroup ‘ref’Cross-reference hyperlinks
linkgroup ‘url’URL hyperlinks
linkgroup ‘xref’Page reference hyperlinks
linkgroup optionsSetting hyperlink types and options
linkgroup optionsSetting group options
linkgroup options, demoHyperlinks (xhyper.tex)
linkgroup typeSetting hyperlink types and options
linkgroup typeSetting group types
links, hypertextHyperlinks
list of figuresAlternative contents files
list of tablesAlternative contents files
listing filesVerbatim listing
listing files, demoHighlighting TeX comments in listings (lscommnt.tex)
listsLists
lists, formattingFormatting lists
lists, hyperlinksList hyperlinks
loading packages, environment forEnvironment for loading packages
logosLogos
lookahead without spaces\futurenonspacelet
loopsIteration
lscommnt.texHighlighting TeX comments in listings (lscommnt.tex)

M
magnification, hyperlink destinationDestination options for pdftex and dvipdfm
makeindexInvoking Eplain
makeindexIndexing
makeindexIndex hyperlinks
margins, changingMargins
margins, index terms inProofing index terms
mathematics displays, formattingDisplays
mathematics displays, hyperlinksOptions supported by all drivers
mathematics displays, hyperlinksSetting group options
MetafontLogos
microtype.styPackages known not to work
miniltx.texLoading LaTeX packages
minimal realizationsConstruction of commutative diagrams
modifying index entries’ page numbersModifying index entries
morphismsArrows and morphisms
multiple column outputMultiple columns
multiple indexesIndexing

N
named destinationLink types for hypertex
named destinationLink types for pdftex and dvipdfm
names, of TeX variantsLogos
new window, opening hyperlink inLink options for pdftex and dvipdfm
newlinecharDiagnostics
newlines, obeyingObeying spaces
nolinks, hyperlink driverHyperlink driver nolinks
numbered destinationLink types for pdftex and dvipdfm
numbered listsLists
numbered referencesCitations
numbers, detecting\ifinteger and \isinteger
numbers, written form ofWriting out numbers

O
omitting hyperlinksHyperlink driver nolinks
omitting hyperlinksTurning hyperlinks on/off
omitting typesetting of graphicsPackages known to work
open boxesBoxes
OpTeXIntroduction
option list, groupSetting group options
option list, preserving for groupSetting group options
options, destination, commonOptions supported by all drivers
options, destination, dvipdfmDestination options for pdftex and dvipdfm
options, destination, hypertexDestination options for hypertex
options, destination, pdftexDestination options for pdftex and dvipdfm
options, link and destinationIntroduction to hyperlinks
options, link, commonOptions supported by all drivers
options, link, dvipdfmLink options for pdftex and dvipdfm
options, link, hypertexLink options for hypertex
options, link, pdftexLink options for pdftex and dvipdfm
ordered listLists
outlines, making PDFMaking PDF outlines
output routine and index proofingProofing index terms
overstrikingPackages known to work

P
packages, LaTeXLoading LaTeX packages
packages, LaTeXPackages known to work
packages, LaTeXPackages known not to work
page destinationLink types for pdftex and dvipdfm
page list, parsingPage destinations for index terms
page range, parsingPage destinations for index terms
page reference hyperlinkPage reference hyperlinks
page-breaking, preserving with hyperlinksHyperlink driver nolinks
parsing page numbersPage destinations for index terms
Patashnik, OrenCitations
pathnames, breakingPaths
pathnames, breakingPackages known to work
PDFPackages known to work
PDF outlines (a.k.a. bookmarks)Making PDF outlines
PDF outputChecking for PDF output
pdftexInvoking Eplain
pdftexIntroduction to hyperlinks
pdftex, destination optionsDestination options for pdftex and dvipdfm
pdftex, destination typesDestination types for pdftex and dvipdfm
pdftex, hyperlink driverHyperlink drivers pdftex and dvipdfm
pdftex, link optionsLink options for pdftex and dvipdfm
pdftex, link typesLink types for pdftex and dvipdfm
pdftex, making PDF outlines forMaking PDF outlines
pdfTeX, problems using color and graphicsPackages known to work
pdfTeX, problems with supp-mis.texPackages known to work
pict2e.styPackages known not to work
picture modePackages known to work
picture modeSlanted lines and vectors
Portable Document FormatPackages known to work
PostScript pointDestination types for pdftex and dvipdfm
PostScript pointDestination options for pdftex and dvipdfm
PostScript pointLink options for pdftex and dvipdfm
proofing index termsProofing index terms
propertiesProperties
ps2pdfHyperlink driver hypertex
ps2pdfHyperlink driver hypertex
psfrag.styPackages known to work

Q
quadruple column outputMultiple columns

R
Rahtz, SebastianLoading LaTeX packages
raising hyperlink destinationsOptions supported by all drivers
raising hyperlink destinationsSetting group options
ranges and index entryModifying index entries
recognizing numbers\ifinteger and \isinteger
rectanglesBoxes
references, alphanumericCitations
references, defining generalDefining generic references
references, defining generalUsing generic references
references, numberedCitations
register allocationAllocation macros
registers, scratchScratch registers
restoring \input, LaTeX packagesEnvironment for loading packages
return characterCategory codes
right-justificationJustification
rmsIntroduction
rotationPackages known to work
rotation, demoHyperlinks (xhyper.tex)
rule thicknessRules
run:’ linksGeneral hyperlinks

S
scalingPackages known to work
scaling, demoHyperlinks (xhyper.tex)
scratch registersScratch registers
sedCustomizing indexing
see also index entries and hyperlinksHyperlinks in see and see also entries
see also index entries and sortingCustomizing indexing
see, and index entriesModifying index entries
see, and index entriesCustomizing indexing
see, and index entries, hyperlinksHyperlinks in see and see also entries
short contentsReading the .toc file
silent indexingIndexing terms
skipping tokens\ifundefined
skipping tokens\ifempty
SLiTeXLogos
Snake LemmaArrows and morphisms
solid hyperlink borderLink options for pdftex and dvipdfm
sorting an indexIndexing
sorting of index entriesIndexing commands
soul.styPackages known to work
space above index entriesTypesetting an index
spaces, ignoring\futurenonspacelet
spaces, obeyingObeying spaces
spaces, trailing and indexing commandsIndexing terms
spacing outPackages known to work
spacing, preserving with hyperlinksHyperlink driver nolinks
special charactersVerbatim listing
special characters, in index entriesIndex entries with special characters
special characters, in table of contentsWriting the .toc file
Stallman, RichardIntroduction
striking outPackages known to work
style, hyperlink borderLink options for pdftex and dvipdfm
subequations, referring toSubequation references
subterm in indexingIndexing terms
supp-mis.tex, problems with pdfTeXPackages known to work
supp-pdf.texPackages known to work

T
table of contentsContents
table of contents, and verbatim textWriting the .toc file
table of contents, hyperlinksContents hyperlinks
table of contents, shortReading the .toc file
table of contents, shortMacro arguments
tablesTables
tabsObeying spaces
TeX by TopicIteration
TeX Frequently Asked Questions\ifinteger and \isinteger
TEXFORMATSInstallation
texi2dviInvoking Eplain
texi2dviCitations
texi2dviIndexing
TexinfoIntroduction
TEXINPUTSInstallation
texnames.styLogos
time of dayTime of day
toc files, writing severalChanging the .toc file's root name
tracingDiagnostics
trailing spaces and indexing commandsIndexing terms
trimseeCustomizing indexing
triple column outputMultiple columns
Tu, Loring W.Construction of commutative diagrams
TUGboatIntroduction
type, link and destinationIntroduction to hyperlinks
types, destination, dvipdfmDestination types for pdftex and dvipdfm
types, destination, hypertexDestination types for hypertex
types, destination, pdftexDestination types for pdftex and dvipdfm
types, link, dvipdfmLink types for pdftex and dvipdfm
types, link, hypertexLink types for hypertex
types, link, pdftexLink types for pdftex and dvipdfm
typesetting an indexTypesetting an index

U
undefined control sequence, checking for\ifundefined
undefined labels, warnings aboutInstallation
underline hyperlink borderLink options for pdftex and dvipdfm
underliningPackages known to work
underlining page numbers in indexPage list and page range parsers
universal mapping propertyConstruction of commutative diagrams
unordered listsLists
upgradingInstallation
url for path.styPaths
url hyperlinkGeneral hyperlinks
url hyperlinkURL hyperlinks
url hyperlinkLink types for hypertex
url hyperlinkLink types for pdftex and dvipdfm
url.styPackages known to work
url.styURL hyperlinks
url.styHyperlinks (xhyper.tex)
user-inaccessible macrosCategory codes

V
vectorsSlanted lines and vectors
verbatim listingVerbatim listing
verbatim listing, demoHighlighting TeX comments in listings (lscommnt.tex)
verbatim text, in indexIndex entries with special characters
verbatim text, in table of contentsWriting the .toc file
version numberIntroduction

W
Walden, DavidIntroduction
Warner, Frank W.Construction of commutative diagrams
whatsits made by hyperlinksHyperlink driver nolinks
whatsits made by index entriesIndexing commands
while loopsIteration
whitespaceObeying spaces
width, hyperlink borderLink options for pdftex and dvipdfm
writing several toc filesChanging the .toc file's root name

X
xcolor.styPackages known not to work
xdviHyperlink driver hypertex
XeLaTeXLogos
xeplain.texIntroduction
XeTeXLogos
xhyper.texHyperlinks (xhyper.tex)

Z
Zassenhaus, HansConstruction of commutative diagrams
zooming, hyperlink destinationDestination options for pdftex and dvipdfm