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- % \begin{meta-comment}
- %
- % $Id$
- %
- % Allow @-commands
- %
- % (c) 1995 Mark Wooding
- %
- %----- Revision history -----------------------------------------------------
- %
- % $Log$
- % Revision 1.1 2000-07-13 09:10:20 michael
- % + Initial import
- %
- % Revision 1.1 1998/09/21 10:18:06 michael
- % Initial implementation
- %
- % Revision 1.3 1996/11/19 20:46:55 mdw
- % Entered into RCS
- %
- %
- % \end{meta-comment}
- %
- % \begin{meta-comment} <general public licence>
- %%
- %% at package -- support for `@' commands'
- %% Copyright (c) 1996 Mark Wooding
- %%
- %% This program is free software; you can redistribute it and/or modify
- %% it under the terms of the GNU General Public License as published by
- %% the Free Software Foundation; either version 2 of the License, or
- %% (at your option) any later version.
- %%
- %% This program is distributed in the hope that it will be useful,
- %% but WITHOUT ANY WARRANTY; without even the implied warranty of
- %% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- %% GNU General Public License for more details.
- %%
- %% You should have received a copy of the GNU General Public License
- %% along with this program; if not, write to the Free Software
- %% Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- %%
- % \end{meta-comment}
- %
- % \begin{meta-comment} <Package preamble>
- %<+package>\NeedsTeXFormat{LaTeX2e}
- %<+package>\ProvidesPackage{at}
- %<+package> [1996/05/02 1.3 @-command support (MDW)]
- % \end{meta-comment}
- %
- % \CheckSum{355}
- %% \CharacterTable
- %% {Upper-case \A\B\C\D\E\F\G\H\I\J\K\L\M\N\O\P\Q\R\S\T\U\V\W\X\Y\Z
- %% Lower-case \a\b\c\d\e\f\g\h\i\j\k\l\m\n\o\p\q\r\s\t\u\v\w\x\y\z
- %% Digits \0\1\2\3\4\5\6\7\8\9
- %% Exclamation \! Double quote \" Hash (number) \#
- %% Dollar \$ Percent \% Ampersand \&
- %% Acute accent \' Left paren \( Right paren \)
- %% Asterisk \* Plus \+ Comma \,
- %% Minus \- Point \. Solidus \/
- %% Colon \: Semicolon \; Less than \<
- %% Equals \= Greater than \> Question mark \?
- %% Commercial at \@ Left bracket \[ Backslash \\
- %% Right bracket \] Circumflex \^ Underscore \_
- %% Grave accent \` Left brace \{ Vertical bar \|
- %% Right brace \} Tilde \~}
- %%
- %
- % \begin{meta-comment} <driver>
- %
- %<*driver>
- \input{mdwtools}
- \describespackage{at}
- \aton
- \atlet p=\package
- \atdef at{\package{at}}
- \atdef={\mbox{-}}
- \atdef-{@@@=}
- \atlet.=\syntax
- \mdwdoc
- %</driver>
- %
- % \end{meta-comment}
- %
- % \section{User guide}
- %
- % The @at\ package is an attempt to remove a lot of tedious typing that
- % ends up in \LaTeX\ documents, by expanding the number of short command
- % names available. The new command names begin with the `|@|' character,
- % rather than the conventional `|\|', so you can tell them apart.
- %
- % The package provides some general commands for defining @-commands, and
- % then uses them to define some fairly simple ones which will be useful to
- % most people.
- %
- % The rules for @-command names aren't terribly complex:
- % \begin{itemize}
- % \item If the first character of the name is a letter, then the command name
- % consists of all characters up to, but not including, the first
- % nonletter. Spaces following the command name are ignored.
- % \item If the first character of the name is a backslash, then the @-command
- % name consists of the control sequence introduced by the backslash.
- % \item Otherwise, the command name consists only of that first character.
- % Spaces following the name are not ignored, unless that character
- % was itself a space character.
- % \end{itemize}
- %
- % Usually, digits are not considered to be letters. However, the
- % \package{at} package will consider digits to be letters if you give it the
- % \textsf{digits} option in the |\usepackage| command. (Note that this
- % only affects the \package{at} package; it won't change the characters
- % allowed in normal command names.)
- %
- % \DescribeMacro{\atallowdigits}
- % \DescribeMacro{\atdisallowdigits}
- % You can enable and disable digits being considered as letters dynamically.
- % The |\atallowdigits| command allows digits to be used as letters;
- % |\atdisallowdigits| prevents this. Both declarations follow \LaTeX's
- % usual scoping rules. Both of these commands have corresponding
- % environments with the same names (without the leading `|\|', obviously).
- %
- % \subsection{Defining @-commands}
- %
- % \DescribeMacro{\newatcommand}
- % \DescribeMacro{\renewatcommand}
- % The |\newatcommand| command will define a new @-command using a syntax
- % similar to |\newcommand|. For example, you could define
- % \begin{listing}
- %\newatcommand c[1]{\chapter{#1}}
- % \end{listing}
- % to make @.{"@c{"<name>"}"} equivalent to @.{"\\chapter{"<name>"}"}.
- %
- % A |\renewatcommand| is also provided to redefine existing commands, should
- % the need arise.
- %
- % \DescribeMacro{\atdef}
- % For \TeX\ hackers, the |\atdef| command defines @-commands using a syntax
- % similar to \TeX's built-in |\def|.
- %
- % As an example, the following command makes @.{"@/"<text>"/"} write its
- % argument \<text> in italics:
- % \begin{listing}
- %\atdef/#1/{\textit{#1}}
- % \end{listing}
- % The real implementation of the |@/|\dots|/| command is a bit more
- % complex, and is given in the next section.
- %
- % You can use all of \TeX's features for defining the syntax of your
- % command. (See chapter~20 of @/The \TeX book/ for more details.)
- %
- % \DescribeMacro{\atlet}
- % Since |\atdef| is provided to behave similarly to |\def|, @at\ provides
- % |\atlet| which works similarly to |\let|. For example you can say
- % \begin{listing}
- %\atlet!=\index
- % \end{listing}
- % to allow the short |@!| to behave exactly like |\index|.
- %
- % Note that all commands defined using these commands are robust even if you
- % use fragile commands in their definitions. Unless you start doing very
- % strange things, @-commands never need |\protect|ing.
- %
- % \subsection{Predefined @-commands}
- %
- % A small number of hopefully useful commands are provided by default.
- % These are described in the table below:
- %
- % \bigskip \begin{center} \begin{tabular}{lp{3in}} \hline
- % \bf Command & \bf Meaning \\ \hline
- % @.{"@@"} & Typesets an `@@' character. \\
- % @.{"@/"<text>"/"} & In text (LR or paragraph) mode, typesets its
- % argument emphasised. In maths mode, it
- % always chooses italics. \\
- % @.{"@*"<text>"*"} & Typesets its argument \<text> in bold. \\
- % @.{"@i{"<text>"}"} & Equivalent to `@.{"\\index{"<text>"}"}'. \\
- % @.{"@I{"<text>"}"} & As for |@i|, but also writes its argument
- % to the document. \\ \hline
- % \end{tabular} \end{center} \bigskip
- %
- % Package writers should not rely on any predefined @-commands -- they're
- % provided for users, and users should be able to redefine them without
- % fear of messing anything up. (This includes the `standard' commands
- % provided by the @at\ package, by the way. They're provided in the vague
- % hope that they might be useful, and as examples.)
- %
- % \implementation
- %
- % \section{Implementation}
- %
- % \begin{macrocode}
- %<*package>
- % \end{macrocode}
- %
- % \subsection{Options handling}
- %
- % We need a switch to say whether digits should be allowed. Since this
- % is a user thing, I'll avoid |\newif| and just define the thing by hand.
- %
- % \begin{macrocode}
- \def\atallowdigits{\let\ifat@digits\iftrue}
- \def\atdisallowdigits{\let\ifat@digits\iffalse}
- % \end{macrocode}
- %
- % Now define the options.
- %
- % \begin{macrocode}
- \DeclareOption{digits}{\atallowdigits}
- \DeclareOption{nodigits}{\atdisallowdigits}
- \ExecuteOptions{nodigits}
- \ProcessOptions
- % \end{macrocode}
- %
- % \subsection{How the commands work}
- %
- % Obviously we make the `@@' character active. It inspects the next
- % character (or argument, actually -- it can be enclosed in braces for
- % longer commands, although this is a bit futile), and builds the command
- % name from that.
- %
- % The |\at| command is equivalent to the active `@@' character always.
- %
- %
- % \subsection{Converting command names}
- %
- % We need to be able to read an @-command name, and convert it to a normal
- % \TeX\ control sequence. First, we declare some control sequences for
- % braces, which we need later.
- %
- % \begin{macrocode}
- \begingroup
- \catcode`\<1
- \catcode`\>2
- \catcode`\{12
- \catcode`\}12
- \gdef\at@lb<{>
- \gdef\at@rb<}>
- \gdef\at@spc< >
- \endgroup
- % \end{macrocode}
- %
- % I'll set up some helper routines now, to help me read the command
- % names. The way this works is that we |\futurelet| the token into
- % |\@let@token|. These routines will then sort out what to do next.
- %
- % \begin{macro}{\at@test}
- %
- % Given an |\if|\dots\ test, does its first or second argument.
- %
- % \begin{macrocode}
- \def\at@test#1\then{%
- #1\expandafter\@firstoftwo\else\expandafter\@secondoftwo\fi%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@ifcat}
- %
- % Checks the category code of the current character. If it matches the
- % argument, it does its second argument, otherwise it does the third.
- %
- % \begin{macrocode}
- \def\at@ifcat#1{\at@test\ifcat#1\noexpand\@let@token\then}
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@ifletter}
- %
- % This routine tests the token to see if it's a letter, and if so adds
- % it to the token list and does the first argument; otherwise it does the
- % second argument. It accepts digits as letters if the switch is turned
- % on.
- %
- % There's some fun later, so I'll describe this slowly. First, we compare
- % the category code to a letter, and if we have a match, we know we're done;
- % we need to pick up the letter as an argument. If the catcode is `other',
- % we must compare with numbers to see if it's in range.
- %
- % \begin{macrocode}
- \def\at@ifletter#1#2{%
- \at@ifcat x%
- {\at@ifletter@ii{#1}}%
- {\at@ifcat 0%
- {\at@ifletter@i{#1}{#2}}%
- {#2}%
- }%
- }
- % \end{macrocode}
- %
- % Right. It's `other' (so it's safe to handle as a macro argument) and we
- % need to know if it's a digit. This is a little tricky: I use |\if| to
- % compare two characters. The first character is~`1' or~`0' depending on the
- % `digit' switch; the second is~`1' or~`x' depending on whether it's actually
- % a digit. They'll only match if everything's worked out OK.
- %
- % \begin{macrocode}
- \def\at@ifletter@i#1#2#3{%
- \at@test\if%
- \ifat@digits1\else0\fi%
- \ifnum`#3<`0x\else\ifnum`#3>`9x\else1\fi\fi%
- \then%
- {\at@ifletter@ii{#1}{#3}}%
- {#2#3}%
- }
- % \end{macrocode}
- %
- % Right; we have the character, so add it to the list and carry on.
- %
- % \begin{macrocode}
- \def\at@ifletter@ii#1#2{\toks@\expandafter{\the\toks@#2}#1}
- % \end{macrocode}
- %
- % \end{macro}
- %
- % Now we define the command name reading routines. We have @/almost/ the
- % same behaviour as \TeX, although we can't support `|%|' characters for
- % reasons to do with \TeX's tokenising algorithm.
- %
- % \begin{macro}{\at@read@name}
- %
- % The routine which actually reads the command name works as follows:
- % \begin{enumerate}
- % \item Have a peek at the next character. If it's a left or right brace,
- % then use the appropriate character.
- % \item If the character is not a letter, just use the character (or whole
- % control sequence.
- % \item Finally, if it's a letter, keep reading letters until we find one
- % that wasn't.
- % \end{enumerate}
- %
- % First, we do some setting up and read the first character
- %
- % \begin{macrocode}
- \def\at@read@name#1{%
- \let\at@next=#1%
- \toks@{}%
- \futurelet\@let@token\at@rn@i%
- }
- % \end{macrocode}
- %
- % Next, sort out what to do, based on the category code.
- %
- % \begin{macrocode}
- \def\at@rn@i{%
- \def\@tempa{\afterassignment\at@rn@iv\let\@let@token= }%
- \at@ifletter%
- {\futurelet\@let@token\at@rn@iii}%
- {\at@ifcat\bgroup%
- {\toks@\expandafter{\at@lb}\@tempa}%
- {\at@ifcat\egroup%
- {\toks@\expandafter{\at@rb}\@tempa}%
- {\at@ifcat\at@spc%
- {\toks@{ }\@tempa}%
- {\at@rn@ii}%
- }%
- }%
- }%
- }
- % \end{macrocode}
- %
- % Most types of tokens can be fiddled using |\string|.
- %
- % \begin{macrocode}
- \def\at@rn@ii#1{%
- \toks@\expandafter{\string#1}%
- \at@rn@iv%
- }
- % \end{macrocode}
- %
- % We've found a letter, so we should check for another one.
- %
- % \begin{macrocode}
- \def\at@rn@iii{%
- \at@ifletter%
- {\futurelet\@let@token\at@rn@iii}%
- {\@ifnextchar.\at@rn@iv\at@rn@iv}%
- }
- % \end{macrocode}
- %
- % Finally, we need to pass the real string, as an argument, to the
- % macro. We make |\@let@token| relax, since it might be something which will
- % upset \TeX\ later, e.g., a |#| character.
- %
- % \begin{macrocode}
- \def\at@rn@iv{%
- \let\@let@token\relax%
- \expandafter\at@next\csname at.\the\toks@\endcsname%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@cmdname}
- %
- % Given a control sequence, work out which @-command it came from.
- %
- % \begin{macrocode}
- \def\at@cmdname#1{\expandafter\at@cmdname@i\string#1\@@foo}
- % \end{macrocode}
- %
- % Now extract the trailing bits.
- %
- % \begin{macrocode}
- \def\at@cmdname@i#1.#2\@@foo{#2}
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@decode}
- %
- % The |\at@decode| macro takes an extracted @-command name, and tries to
- % execute the correct control sequence derived from it.
- %
- % \begin{macrocode}
- \def\at@decode#1{%
- \at@test\ifx#1\relax\then{%
- \PackageError{at}{Unknown @-command `@\at@cmdname#1'}{%
- The @-command you typed wasn't recognised, so I've ignored it.
- }%
- }{%
- #1%
- }%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\@at}
- %
- % We'd like a measure of compatibility with @p{amsmath}. The @-commands
- % provided by @p{amsmath} work only in maths mode, so this gives us a way of
- % distinguishing. If the control sequence |\Iat| is defined, and we're in
- % maths mode, we'll call that instead of doing our own thing.
- %
- % \begin{macrocode}
- \def\@at{%
- \def\@tempa{\at@read@name\at@decode}%
- \ifmmode\ifx\Iat\not@@defined\else%
- \let\@tempa\Iat%
- \fi\fi%
- \@tempa%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- %
- % \subsection{Defining new commands}
- %
- % \begin{macro}{\at@buildcmd}
- %
- % First, we define a command to build these other commands:
- %
- % \begin{macrocode}
- \def\at@buildcmd#1#2{%
- \expandafter\def\csname\expandafter
- \@gobble\string#1@decode\endcsname##1{#2##1}%
- \edef#1{%
- \noexpand\at@read@name%
- \expandafter\noexpand%
- \csname\expandafter\@gobble\string#1@decode\endcsname%
- }%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\newatcommand}
- % \begin{macro}{\renewatcommand}
- % \begin{macro}{\provideatcommand}
- % \begin{macro}{\atdef}
- % \begin{macro}{\atshow}
- %
- % Now we define the various operations on @-commands.
- %
- % \begin{macrocode}
- \at@buildcmd\newatcommand\newcommand
- \at@buildcmd\renewatcommand\renewcommand
- \at@buildcmd\provideatcommand\providecommand
- \at@buildcmd\atdef\def
- \at@buildcmd\atshow\show
- % \end{macrocode}
- %
- % \end{macro}
- % \end{macro}
- % \end{macro}
- % \end{macro}
- % \end{macro}
- %
- % \begin{macro}{\atlet}
- %
- % |\atlet| is rather harder than the others, because we want to allow people
- % to say things like @.{"\\atlet"<name>"=@"<name>}. The following hacking
- % does the trick. I'm trying very hard to duplicate |\let|'s behaviour with
- % respect to space tokens here, to avoid any surprises, although there
- % probably will be some differences. In particular, |\afterassignment|
- % won't work in any sensible way.
- %
- % First, we read the name of the @-command we're defining. We also open
- % a group, to stop messing other people up, and make `@@' into an `other'
- % token, so that it doesn't irritatingly look like its meaning as a control
- % sequence.
- %
- % \begin{macrocode}
- \def\atlet{%
- \begingroup%
- \@makeother\@%
- \at@read@name\atlet@i%
- }
- % \end{macrocode}
- %
- % Put the name into a scratch macro for later use. Now see if there's an
- % equals sign up ahead. If not, this will gobble any spaces in between the
- % @-command name and the argument.
- %
- % \begin{macrocode}
- \def\atlet@i#1{%
- \def\at@temp{#1}%
- \@ifnextchar=\atlet@ii{\atlet@ii=}%
- }
- % \end{macrocode}
- %
- % Now we gobble the equals sign (whatever catcode it is), and peek at the
- % next token up ahead using |\let| with no following space.
- %
- % \begin{macrocode}
- \def\atlet@ii#1{\afterassignment\atlet@iii\global\let\at@gnext=}
- % \end{macrocode}
- %
- % The control sequence |\at@gnext| is now |\let| to be whatever we want the
- % @-command to be, unless it's picked up an `@@' sign. If it has, we've
- % eaten the |@| token, so just read the name and pass it on. Otherwise,
- % we can |\let| the @-command directly to |\at@gnext|. There's some
- % nastiness here to make |\the\toks@| expand before we close the group and
- % restore its previous definition.
- %
- % \begin{macrocode}
- \def\atlet@iii{%
- \if @\noexpand\at@gnext%
- \expandafter\at@read@name\expandafter\atlet@iv%
- \else%
- \expandafter\endgroup%
- \expandafter\let\at@temp= \at@gnext%
- \fi%
- }
- % \end{macrocode}
- %
- % We've read the source @-command name, so just copy the definitions over.
- %
- % \begin{macrocode}
- \def\atlet@iv#1{%
- \expandafter\endgroup%
- \expandafter\let\at@temp=#1%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- %
- % \subsection{Robustness of @-commands}
- %
- % We want all @-commands to be robust. We could leave them all being
- % fragile, although making robust @-commands would then be almost impossible.
- % There are two problems which we must face:
- %
- % \begin{itemize}
- %
- % \item The `|\@at|' command which scans the @-command name is (very)
- % fragile. I could have used |\DeclareRobustCommand| for it (and in
- % fact I did in an earlier version), but that doesn't help the other
- % problem at all.
- %
- % \item The `name' of the @-command may contain active characters or control
- % sequences, which will be expanded at the wrong time unless we do
- % something about it now.
- %
- % \end{itemize}
- %
- % We must also be careful not to introduce extra space characters into any
- % files written, because spaces are significant in @-commands. Finally,
- % we have a minor problem in that most auxiliary files are read in with
- % the `@@' character set to be a letter.
- %
- % \begin{macro}{\at}
- %
- % Following the example of \LaTeX's `short' command handling, we'll define
- % |\at| to decide what to do depending on what |\protect| looks like. If
- % we're typesetting, we just call |\@at| (above) and expect it to cope.
- % Otherwise we call |\at@protect|, which scoops up the |\fi| and the |\@at|,
- % and inserts other magic.
- %
- % \begin{macrocode}
- \def\at{\ifx\protect\@typeset@protect\else\at@protect\fi\@at}
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@protect}
- %
- % Since we gobbled the |\fi| from the above, we must put that back. We then
- % need to do things which are more complicated. If |\protect| is behaving
- % like |\string|, then we do one sort of protection. Otherwise, we assume
- % that |\protect| is being like |\noexpand|.
- %
- % \begin{macrocode}
- \def\at@protect\fi#1{%
- \fi%
- \ifx\protect\string%
- \expandafter\at@protect@string%
- \else%
- \expandafter\at@protect@noexpand%
- \fi%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@protect@string}
- %
- % When |\protect| is |\string|, we don't need to be able to recover the
- % original text particularly accurately -- it's for the user to look at.
- % Therefore, we just output a $|@|_{11}$ and use |\string| on the next
- % token. This must be sufficient, since we only allow multi-token command
- % names if the first token is a letter (code~11).
- %
- % \begin{macrocode}
- \def\at@protect@string{@\string}
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\at@protect@noexpand}
- %
- % This is a little more complex, since we're still expecting to be executed
- % properly at some stage. However, there's a cheeky dodge we can employ
- % since the |\at| command is thoroughly robustified (or at least it will be
- % by the time we've finished this). All |\@unexpandable@protect| does
- % is confer repeated robustness on a fragile command. Since our command
- % is robust, we don't need this and we can get away with just using a
- % single |\noexpand|, both for the |\@at@| command and the following token
- % (which we must robustify, because no-one else can do it for us -- if
- % anyone tries, they end up using the |@\protect| command which is rather
- % embarassing).
- %
- % I'll give the definition, and then examine how this expands in various
- % cases.
- %
- % \begin{macrocode}
- \def\at@protect@noexpand{\noexpand\@at@ @\noexpand}
- \def\@at@#1{\at}
- % \end{macrocode}
- %
- % A few points, before we go into the main examination of the protection.
- % I've inserted a $|@|_{11}$ token, which is gobbled by |\@at@| when the
- % thing is finally expanded fully. This prevents following space tokens
- % in an |\input| file from being swallowed because they follow a control
- % sequence. (I can't use the normal $|@|_{13}$ token, because when files
- % like the |.aux| file are read in, |@| is given code~11 by
- % |\makeatletter|.)
- %
- % \setbox0\hbox{|@at@|}
- % Now for a description of why this works. When |\at| is expanded, it works
- % out that |\protect| is either |\noexpand| or |\@unexpandable@protect|, and
- % becomes |\at@protect@noexpand|. Because of the |\noexpand| tokens, this
- % stops being expanded once it reaches $\fbox{\box0}\,|@|_{11}\,x$ (where
- % $x$ is the token immediately following the $|@|_{13}$ character). If this
- % is expanded again, for example in another |\edef|, or in a |\write| or a
- % |\mark|, the |\@at@| wakes up, gobbles the following |@| (whatever catcode
- % it is -- there may be intervening |\write| and |\input| commands) and
- % becomes |\at|, and the whole thing can start over again.
- %
- % \end{macro}
- %
- %
- % \subsection{Enabling and disabling @-commands}
- %
- % \begin{macro}{\aton}
- %
- % We define the |\aton| command to enable all of our magic. We store
- % the old catcode in the |\atoff| command, make `@@' active, and make it
- % do the stuff.
- %
- % \begin{macrocode}
- \def\aton{%
- \ifnum\catcode`\@=\active\else%
- \edef\atoff{\catcode`\noexpand\@\the\catcode`\@}%
- \catcode`\@\active%
- \lccode`\~`\@%
- \lowercase{\let~\at}%
- \fi%
- }
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\atoff}
- %
- % The |\atoff| command makes `@@' do the stuff it's meant to. We remember
- % the old catcode and revert to it. This is largely unnecessary.
- %
- % \begin{macrocode}
- \def\atoff{\catcode`\@12}
- % \end{macrocode}
- %
- % \end{macro}
- %
- % \begin{macro}{\makeatother}
- %
- % Now we make our active `@@' the default outside of package files.
- %
- % \begin{macrocode}
- \let\makeatother\aton
- % \end{macrocode}
- %
- % \end{macro}
- %
- % And we must make sure that the user can use all of our nice commands.
- % Once the document starts, we allow @-commands.
- %
- % \begin{macrocode}
- \AtBeginDocument{\aton}
- % \end{macrocode}
- %
- % \begin{macro}{\dospecials}
- % \begin{macro}{\@sanitize}
- %
- % We must add the `@@' character to the various specials lists.
- %
- % \begin{macrocode}
- \expandafter\def\expandafter\dospecials\expandafter{\dospecials\do\@}
- \expandafter\def\expandafter\@sanitize\expandafter{%
- \@sanitize\@makeother\@}
- % \end{macrocode}
- %
- % \end{macro}
- % \end{macro}
- %
- % \subsection{Default @-commands}
- %
- % We define some trivial examples to get the user going.
- %
- % \begin{macrocode}
- \expandafter\chardef\csname at.@\endcsname=`\@
- \atdef*#1*{\ifmmode\mathbf{#1}\else\textbf{#1}\fi}
- \atdef/#1/{\ifmmode\mathit{#1}\else\emph{#1}\fi}
- \atlet i=\index
- \atdef I#1{#1\index{#1}}
- %</package>
- % \end{macrocode}
- %
- % \hfill Mark Wooding, \today
- %
- % \Finale
- %
- \endinput
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