86f6a31e |
1 | % \begin{meta-comment} |
2 | % |
3 | % $Id: sverb.dtx,v 1.1 2002/02/03 20:49:03 mdw Exp $ |
4 | % |
5 | % Verbatim typesetting done properly (ahem) |
6 | % |
7 | % (c) 1996 Mark Wooding |
8 | % |
9 | %----- Revision history ----------------------------------------------------- |
10 | % |
11 | % $Log: sverb.dtx,v $ |
12 | % Revision 1.1 2002/02/03 20:49:03 mdw |
13 | % Checkin for new build system. |
14 | % |
15 | % Revision 1.3 1996/11/19 21:01:18 mdw |
16 | % Entered into RCS |
17 | % |
18 | % |
19 | % \end{meta-comment} |
20 | % |
21 | % \begin{meta-comment} <general public licence> |
22 | %% |
23 | %% sverb package -- handling of verbatim text |
24 | %% Copyright (c) 1996 Mark Wooding |
25 | %% |
26 | %% This program is free software; you can redistribute it and/or modify |
27 | %% it under the terms of the GNU General Public License as published by |
28 | %% the Free Software Foundation; either version 2 of the License, or |
29 | %% (at your option) any later version. |
30 | %% |
31 | %% This program is distributed in the hope that it will be useful, |
32 | %% but WITHOUT ANY WARRANTY; without even the implied warranty of |
33 | %% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
34 | %% GNU General Public License for more details. |
35 | %% |
36 | %% You should have received a copy of the GNU General Public License |
37 | %% along with this program; if not, write to the Free Software |
38 | %% Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
39 | %% |
40 | % \end{meta-comment} |
41 | % |
42 | % \begin{meta-comment} <Package preamble> |
43 | %<+package>\NeedsTeXFormat{LaTeX2e} |
44 | %<+package>\ProvidesPackage{sverb} |
45 | %<+package> [1996/05/08 1.3 Verbatim typesetting] |
46 | % \end{meta-comment} |
47 | % |
48 | % \CheckSum{651} |
49 | %% \CharacterTable |
50 | %% {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 |
51 | %% 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 |
52 | %% Digits \0\1\2\3\4\5\6\7\8\9 |
53 | %% Exclamation \! Double quote \" Hash (number) \# |
54 | %% Dollar \$ Percent \% Ampersand \& |
55 | %% Acute accent \' Left paren \( Right paren \) |
56 | %% Asterisk \* Plus \+ Comma \, |
57 | %% Minus \- Point \. Solidus \/ |
58 | %% Colon \: Semicolon \; Less than \< |
59 | %% Equals \= Greater than \> Question mark \? |
60 | %% Commercial at \@ Left bracket \[ Backslash \\ |
61 | %% Right bracket \] Circumflex \^ Underscore \_ |
62 | %% Grave accent \` Left brace \{ Vertical bar \| |
63 | %% Right brace \} Tilde \~} |
64 | %% |
65 | % |
66 | % \begin{meta-comment} |
67 | % |
68 | %<*driver> |
69 | \input{mdwtools} |
70 | \describespackage{sverb} |
71 | \mdwdoc |
72 | %</driver> |
73 | % |
74 | % \end{meta-comment} |
75 | % |
76 | % \section{User guide} |
77 | % |
78 | % The \package{sverb} package provides some useful commands and environments |
79 | % for doing things with verbatim text. I prefer this code to the standard |
80 | % \package{verbatim} package (by Rainer Sch\"opf et al.)\ although I'm |
81 | % biased. |
82 | % |
83 | % The package was written to fulfil a particular purpose: I wanted to be able |
84 | % to typeset ARM assembler code, 77~columns wide, on A5~paper, with the |
85 | % fields separated by \textit{tab} characters. It's grown up fairly |
86 | % organically from that, and I've tidied it when I've seen the code get too |
87 | % ugly. |
88 | % |
89 | % The current features are: |
90 | % |
91 | % \begin{itemize} |
92 | % |
93 | % \item A `listing' environment which typesets verbatim text nicely. |
94 | % |
95 | % \item A command to read verbatim text from an external file. |
96 | % |
97 | % \item Support for arbitrary-sized chunks of text without overflowing \TeX's |
98 | % memory. |
99 | % |
100 | % \item Support for \textit{tab} characters in the verbatim text. |
101 | % |
102 | % \item An environment for typesetting demonstrations of \LaTeX\ markup. |
103 | % |
104 | % \item It all works correctly with the \package{doc} system for documenting |
105 | % \LaTeX\ packages. |
106 | % |
107 | % \item A fairly hairy but quite powerful programmer interface to the yukky |
108 | % bits of the package. |
109 | % |
110 | % \end{itemize} |
111 | % |
112 | % The interface is described in its own section, so that more timid readers |
113 | % can avoid it. That said, some of the stuff in this section gets rather |
114 | % technical. |
115 | % |
116 | % Note that this package doesn't even try to do anything with short bits of |
117 | % verbatim text (as handled by the |\verb:...:| command). I have a separate |
118 | % package (\package{syntax}) which does all sorts of horrible things along |
119 | % those lines. |
120 | % |
121 | % \subsection{The \env{listing} environment} |
122 | % |
123 | % \DescribeEnv{listing} |
124 | % The main method for typesetting verbatim text is the \env{listing} |
125 | % environment. This works pretty much the same as the standard |
126 | % \env{verbatim} environment, with some exceptions, which are described |
127 | % below. |
128 | % |
129 | % So that you know exactly what you're getting, here are the rules by which |
130 | % \package{sverb} decides what the verbatim text actually is: |
131 | % |
132 | % \begin{itemize} |
133 | % |
134 | % \item If there's any text, other than spaces, on the same line as the |
135 | % `|\begin{listing}|', then the contents of the environment begins |
136 | % immediately after the closing brace (with all leading spaces |
137 | % preserved). Otherwise, the text begins on the following line. |
138 | % |
139 | % \item If there is any text, other than spaces, before the |
140 | % `|\end{listing}|', but on the same line, this is considered to be the |
141 | % last line of the text; otherwise the text is presumed to have ended |
142 | % at the end of the previous line. |
143 | % |
144 | % \item Any text following the |\end{listing}| on the same line is thrown |
145 | % away. There are good reasons for this, but they're technical. |
146 | % Essentially there's nothing I can do about it. |
147 | % |
148 | % \end{itemize} |
149 | % |
150 | % \begin{figure} |
151 | % \begin{demo}[w]{The \env{listing} environment} |
152 | %\dots in the following code: |
153 | % |
154 | %\begin{listing} |
155 | %init MOV R0,#200 ;Version 2.00 please |
156 | % LDR R1,=&4B534154 ;Magic number (`TASK') |
157 | % ADR R2,appName ;Find application name |
158 | % SWI Wimp_Initialise ;Register as a WIMP task |
159 | %\end{listing} |
160 | % |
161 | %The next step is to \dots |
162 | % \end{demo} |
163 | % \end{figure} |
164 | % |
165 | % Tab characters are supported within the environment: tab stops are set |
166 | % every eighth column, although this can be modified. |
167 | % |
168 | % \subsubsection{Configuring the \env{listing} environment} |
169 | % |
170 | % The text size used in the \env{listing} environment is set by the |
171 | % |\listingsize| command. By default, this is set to |\small|, although you |
172 | % can redefine it in the document preamble, or it can be set in the document |
173 | % class. |
174 | % |
175 | % The amount by which the listing text is indented is controlled by the |
176 | % |\listingindent| length parameter. This is a fixed length, whose default |
177 | % value is 1\,em. |
178 | % |
179 | % \subsubsection{Choosing a different end-text} |
180 | % |
181 | % \DescribeEnv{listing*} |
182 | % The \env{listing} environment is terminated by the exact character sequence |
183 | % `|\end{listing}|'. This isn't too much of a problem, unless you want to |
184 | % include this string in the text. This is achieved by the \env{listing$*$} |
185 | % environment, which allows you to specify the end-text to find as an |
186 | % argument. |
187 | % |
188 | % For example: |
189 | % |
190 | % \begin{demo}{The \env{listing$*$} environment} |
191 | %Type a listing as follows: |
192 | % |
193 | %\begin{listing*}{<end-listing*>} |
194 | %\begin{listing} |
195 | %This is a listing. Yes. |
196 | %\end{listing} |
197 | %<end-listing*> |
198 | %\end{demo} |
199 | % |
200 | % Don't include `special' characters in your chosen end-text unless you know |
201 | % what you're doing. |
202 | % |
203 | % \subsection{Writing text to a file} |
204 | % |
205 | % \DescribeEnv{verbwrite} |
206 | % You can write verbatim text to a file using the \env{verbwrite} |
207 | % environment. The syntax is fairly straightforward: |
208 | % |
209 | % \begin{quote} |
210 | % \syntax{"\\begin{verbwrite}{"<file-name>"}" \dots "\\end{verbwrite}"} |
211 | % \end{quote} |
212 | % |
213 | % The text of the environment is written to the named file. The rules about |
214 | % where the text actually starts and ends are the same as for the |
215 | % \env{listing} environment. |
216 | % |
217 | % There is also a $*$-variant, like \env{listing$*$}, which allows you to |
218 | % choose the end-text. The end-text is the first argument, the filename |
219 | % comes second. |
220 | % |
221 | % There is a restriction on the characters you can write to the file: they |
222 | % must all be considered `printable' by \TeX; otherwise they will be read |
223 | % back in as `\syntax{"^^"<chars>}' which isn't too good. Unfortunately, |
224 | % this includes tab characters, so you can't write them.\footnote{^^A |
225 | % Well, not without doing serious surgery on \TeX\ itself, anyway. } |
226 | % |
227 | % \iffalse [Example time... Ho hum. There is evilness here.] \fi |
228 | %\begin{verbwrite*}{<end-write>}{wrdemo1.tmp} |
229 | %\begin{verbwrite}{wrdemo.tmp} |
230 | %This is some text written to |
231 | %a file near the beginning of |
232 | %the file. |
233 | %\end{verbwrite} |
234 | %<end-write> |
235 | % |
236 | % For example: \verbinput{wrdemo1.tmp} |
237 | % |
238 | % \input{wrdemo1.tmp} \iffalse [Now build the file ;-) ] \fi |
239 | % |
240 | % \subsection{The \cmd\verbinput\ command} |
241 | % |
242 | % \DescribeMacro{\verbinput} |
243 | % You can input a pre-prepared text file exactly as it is in the input using |
244 | % the |\verbinput| command. The filename is given as an argument. For |
245 | % example: |
246 | % |
247 | % \begin{demo}{The \cmd\verbinput\ command} |
248 | %\verbinput{wrdemo.tmp} |
249 | % \end{demo} |
250 | % |
251 | % \subsection{The \env{demo} environment} |
252 | % |
253 | % Package authors need to document their packages, and it's common to want |
254 | % to display examples showing the original text and the output side-by-side |
255 | % (or, when space doesn't permit this, one above the other). Both the |
256 | % \LaTeX\ book and \textit{The \LaTeX\ Companion} contain such examples. |
257 | % |
258 | % The \env{demo} environment allows such displays to be created easily. The |
259 | % syntax of the environment is as follows: |
260 | % |
261 | % \begin{quote} |
262 | % \syntax{"\\begin{demo}["<shape>"]{"<title>"}" \dots "\\end{demo}"} |
263 | % \end{quote} |
264 | % |
265 | % The optional \synt{shape} argument can be either `|w|' (wide), or `|n|' |
266 | % (narrow). A `wide' shape places the input and output one above the other, |
267 | % while the `narrow' shape puts them side-by-side. The default shape is |
268 | % `narrow'. An attractive border is drawn around the display to finish it |
269 | % off nicely. |
270 | % |
271 | % An example: |
272 | % |
273 | %\begin{demo*}{<end-demo>}[w]{The \env{demo} environment} |
274 | %\begin{demo}{From the \textit{\TeX book}} |
275 | %\[ \sum_{p\;\rm prime} |
276 | % f(p) = \int_{t>1} |
277 | % f(t)\,{\rm d}\pi(t) \] |
278 | %\end{demo} |
279 | %<end-demo> |
280 | % |
281 | % \DescribeEnv{demo*} |
282 | % As with the other environments created by this package, there's a |
283 | % $*$-variant which takes the end-text as an argument. |
284 | % |
285 | % |
286 | % \section{Programmer interface} |
287 | % |
288 | % This section describes the publicly available routines provided by the |
289 | % \package{sverb} package. Routines not described here are libable to be |
290 | % changed or even removed without warning, so don't use them. |
291 | % |
292 | % \subsection{Environment hooks} |
293 | % |
294 | % Each of the environments created here works in the same way. For each |
295 | % environment \env{foo}, there's a main command responsible for doing the |
296 | % work, called |\sv@foo|. This is given all the arguments of the normal |
297 | % environment, and two more: |
298 | % |
299 | % \begin{itemize} |
300 | % |
301 | % \item The `end-text' to search for, which marks the end of the environment. |
302 | % |
303 | % \item Some actions to perform after the text has been read and processed. |
304 | % This allows the calling macro to do some extra actions, like closing |
305 | % boxes, etc. |
306 | % |
307 | % \end{itemize} |
308 | % |
309 | % All the environments do is call the main command with appropriate |
310 | % arguments. |
311 | % |
312 | % \subsection{Reading the verbatim text} |
313 | % |
314 | % \DescribeMacro{\sv@read} |
315 | % The main scanning routine is |\sv@read|. It is called with three |
316 | % arguments: |
317 | % |
318 | % \begin{itemize} |
319 | % |
320 | % \item The end-text marking the end of the environment. |
321 | % |
322 | % \item The name of a macro (which must be a single token) which is called |
323 | % with a line of text as its single argument. This is given each |
324 | % line of text which is read from the environment in turn. |
325 | % |
326 | % \item A macro, or other sort of action, which is to be done when the text |
327 | % has been read and processed. |
328 | % |
329 | % \end{itemize} |
330 | % |
331 | % The macro |\sv@read| assumes that the caller has already made some |
332 | % provision for removing the category codes of the following text, by either |
333 | % calling |\@verbatim| or using the construction |
334 | % \begin{listing} |
335 | %\let\do=\@makeother |
336 | %\dospecials |
337 | % \end{listing} |
338 | % |
339 | % \DescribeMacro{\sv@safespc} |
340 | % Note that any space characters you read using |\sv@read| will be catcoded |
341 | % as |\active|. Normally this is OK because |\obeyspaces| (or |
342 | % |\@vobeyspaces|) will be in effect. If you're doing something more exotic, |
343 | % like writing text to a file or building a command string, you can call |
344 | % |\sv@safespc| which defines the active-space character to be a normal |
345 | % whitespace-space when expanded. |
346 | % |
347 | % \implementation |
348 | % |
349 | % \section{Implementation} |
350 | % |
351 | % This section defines several macros and environments which allow verbatim |
352 | % typing, with a high degree of configurability. OK, so this sort of |
353 | % thing's been done so often before that it isn't true, but I don't really |
354 | % care. |
355 | % |
356 | % \begin{macrocode} |
357 | %<*package> |
358 | % \end{macrocode} |
359 | % |
360 | % \subsection{Simple things} |
361 | % |
362 | % To help us build funny macros which involve strange and different category |
363 | % codes, I'll write some simple macros which I can use while building my |
364 | % complicated and clever ones. |
365 | % |
366 | % \begin{macro}{\@cspecials} |
367 | % |
368 | % This macro is used to assist the definition of some of the environments. |
369 | % It makes `|\|', `|{|' and `|}|' into `other' characters, and replaces them |
370 | % with `\verb"|"', `|<|' and `|>|' respectively. Note that `|[|' and `|]|' |
371 | % aren't used, because they make defining commands which take optional |
372 | % arguments awkward. Note that we open a group here. This should be closed |
373 | % using \verb"|endgroup" at the end of the special section. |
374 | % |
375 | % \begin{macrocode} |
376 | \def\@cspecials{% |
377 | \begingroup% |
378 | \catcode`|0% |
379 | \catcode`<1% |
380 | \catcode`>2% |
381 | \catcode`\{12% |
382 | \catcode`\}12% |
383 | \catcode`\\12% |
384 | } |
385 | % \end{macrocode} |
386 | % \end{macro} |
387 | % |
388 | % \begin{macro}{\sv@startlisting} |
389 | % |
390 | % This macro sets everything up nicely for a \env{listing}-type verbatim |
391 | % environment. |
392 | % |
393 | % \begin{macrocode} |
394 | \def\sv@startlisting{% |
395 | \def\par{\@@par\penalty\interlinepenalty}% |
396 | \@@par% |
397 | \leftskip\@totalleftmargin% |
398 | \obeylines% |
399 | \@noligs% |
400 | \let\do\@makeother\dospecials% |
401 | \verbatim@font% |
402 | \frenchspacing% |
403 | \@vobeyspaces% |
404 | \settabwidth% |
405 | \catcode9\active% |
406 | \lccode`\~9\lowercase{\let~\sv@vtab}% |
407 | \lccode`\~13\lowercase{\let~\vinput@cr}% |
408 | \interlinepenalty500% |
409 | } |
410 | % \end{macrocode} |
411 | % |
412 | % \end{macro} |
413 | % |
414 | % \subsection{Tab character handling} |
415 | % |
416 | % One of the things we want to do here is handle tab characters properly. |
417 | % (Here, `properly' means `moving to the next column which is a multiple of |
418 | % eight', the way these things were always meant to.) |
419 | % |
420 | % \begin{macro}{\settabwidth} |
421 | % |
422 | % The tabs used by our tabbed verbatim environments are set up by this |
423 | % routine. It sets the tab width parameter |\svtab| to 8 times the width |
424 | % of a |\tt| space. If you really want, you can redefine this macro. |
425 | % |
426 | % \begin{macrocode} |
427 | \newdimen\svtab |
428 | \def\settabwidth{\setbox\z@\hbox{\texttt{\space}}\svtab8\wd\z@} |
429 | % \end{macrocode} |
430 | % |
431 | % \end{macro} |
432 | % |
433 | % \begin{macro}{\sv@vtab} |
434 | % |
435 | % Here we handle tabs inside verbatim environments. We expect each line to |
436 | % be typeset as a box, using something like |
437 | % |
438 | % \begin{listing} |
439 | %\setbox0\hbox{#1} |
440 | %\leavevmode |
441 | %\box0 |
442 | %\par |
443 | % \end{listing} |
444 | % |
445 | % The idea is that you make tab active, and set it to this macro. We stop |
446 | % the current box, stretch it to the right width, and start another one |
447 | % straight after, so nobody know the difference. The code here is straight |
448 | % from Appendix~D of \textit{The \TeX book}. |
449 | % |
450 | % \begin{macrocode} |
451 | \def\sv@vtab{% |
452 | \hfill\egroup% |
453 | \@tempdima\wd\z@% |
454 | \divide\@tempdima\svtab% |
455 | \multiply\@tempdima\svtab% |
456 | \advance\@tempdima\svtab% |
457 | \wd\z@\@tempdima% |
458 | \leavevmode\box\z@% |
459 | \setbox\z@\hbox\bgroup% |
460 | } |
461 | % \end{macrocode} |
462 | % |
463 | % \end{macro} |
464 | % |
465 | % \begin{macro}{\verbinput} |
466 | % |
467 | % We allow input from a file, by the |\verbinput| command. We display the |
468 | % text pretty much the same as the \env{listing} environment below. |
469 | % |
470 | % We set tab and return active, and get them to do appropriate things. This |
471 | % isn't actually all that hard. |
472 | % |
473 | % \begin{macrocode} |
474 | \def\verbinput#1{% |
475 | \begin{listinglist}% |
476 | \listingsize% |
477 | \sv@startlisting% |
478 | \setbox\z@\hbox\bgroup% |
479 | \input{#1}% |
480 | \sv@stripspc% |
481 | \egroup% |
482 | \ifdim\wd\z@=\z@% |
483 | \ifhmode\par\fi% |
484 | \else% |
485 | \leavevmode\box\z@\par% |
486 | \fi% |
487 | \end{listinglist}% |
488 | } |
489 | % \end{macrocode} |
490 | % |
491 | % \end{macro} |
492 | % |
493 | % \begin{macro}{\vinput@cr} |
494 | % |
495 | % This macro handles return characters while inputting text in |\verbinput|. |
496 | % We just output our current box, and start another. |
497 | % |
498 | % \begin{macrocode} |
499 | \def\vinput@cr{% |
500 | \egroup% |
501 | \leavevmode\box\z@% |
502 | \par% |
503 | \setbox\z@\hbox\bgroup% |
504 | } |
505 | % \end{macrocode} |
506 | % |
507 | % \end{macro} |
508 | % |
509 | % \subsection{Reading verbatim text} |
510 | % |
511 | % The traditional way of reading verbatim text is to use a delimited |
512 | % argument, as described in the \textit{\TeX book}. This works well-ish if |
513 | % the text isn't very long. A better solution would be to pick out the text |
514 | % line-by-line and process it like that. So this is what we do. |
515 | % |
516 | % \begin{macro}{\matcher} |
517 | % |
518 | % For long verbatim environments, we need to be able to find the end text. |
519 | % This is rather tricky. The solution here is rather horrible. The |
520 | % environment picks out each line of the text at a time, as an argument, and |
521 | % tests to see if it contains the text we're after. We do the test in a |
522 | % particularly yukky way: we add the actual target text to the end of the |
523 | % line, and inspect the text following the match to see if the match is at |
524 | % the end. |
525 | % |
526 | % The |\matcher| macro creates a `matcher' which will test strings to see if |
527 | % they contain something interesting. |
528 | % |
529 | % To create a matcher, say |
530 | % \syntax{"\\matcher{"<cmd-name>"}{"<target>"}{"<process-cmd>"}"}. The |
531 | % command \synt{cmd-name} accepts a line of text as an argument and calls |
532 | % the \synt{process-cmd} with the text of the line before the match, or the |
533 | % whole lot. It also sets |\@ifmatched| appropriately. |
534 | % |
535 | % (Having spent ages coming up with this cruft myself, I found some very |
536 | % similar, but slightly better, code in Appendix~D. So I've changed mine to |
537 | % match Donald's. Anyway, credit where it's due: cheers Don.) |
538 | % |
539 | % \begin{macrocode} |
540 | \newif\if@matched |
541 | \def\matcher#1#2#3{% |
542 | \expandafter\def\csname\string#1$match\endcsname##1#2##2##3\end{% |
543 | \ifx##2\relax% |
544 | \@matchedfalse% |
545 | \else% |
546 | \@matchedtrue% |
547 | \fi% |
548 | #3{##1}% |
549 | }% |
550 | \expandafter\def\expandafter#1\expandafter##\expandafter1\expandafter{% |
551 | \csname\string#1$match\endcsname##1#2\relax\end% |
552 | }% |
553 | } |
554 | % \end{macrocode} |
555 | % |
556 | % \end{macro} |
557 | % |
558 | % \begin{macro}{\sv@stripspc} |
559 | % |
560 | % This macro strips any trailing glue in the current horizontal list. This |
561 | % is fairly simple, actually: we just loop while glue is the last item. It's |
562 | % slightly complicated by penalties which \TeX\ puts into the list between |
563 | % the glue items, but we just remove them too. |
564 | % |
565 | % \begin{macrocode} |
566 | \def\sv@stripspc{% |
567 | \unpenalty% |
568 | \ifdim\lastskip=\z@\else% |
569 | \unskip\expandafter\sv@stripspc% |
570 | \fi% |
571 | } |
572 | % \end{macrocode} |
573 | % |
574 | % \end{macro} |
575 | % |
576 | % \begin{macro}{\sv@percent} |
577 | % |
578 | % This macro strips a single leading percent character if there is one, and |
579 | % if the \env{doc} package is loaded. We store the possibly stripped text in |
580 | % |\@tempa|. |
581 | % |
582 | % \begin{macrocode} |
583 | \begingroup |
584 | \catcode`\%=12 |
585 | \gdef\sv@percent#1#2\relax |
586 | {\ifx\check@percent\@@undefined |
587 | \ifx#1\relax\def\@tempa{}\else |
588 | \def\@tempa{#1#2}\fi\else |
589 | \ifx#1\relax\def\@tempa{}\else |
590 | \ifx#1%\def\@tempa{#2}\else |
591 | \def\@tempa{#1#2}\fi\fi\fi} |
592 | \endgroup |
593 | % \end{macrocode} |
594 | % |
595 | % \end{macro} |
596 | % |
597 | % \begin{macro}{\@isspaces} |
598 | % |
599 | % We want to avoid writing the first and last lines of the environment to the |
600 | % file if there's nothing in them. To do this, we need to know whether a |
601 | % piece of text contains only space characters. This macro does this, in a |
602 | % rather nasty way. See the other macros below for details of how this |
603 | % works. |
604 | % |
605 | % We define |\sv@safespc| at the same time: this makes space active and |
606 | % expand to a space character which is not active. Neat, huh? |
607 | % |
608 | % \begin{macrocode} |
609 | \lccode`\~32 |
610 | \lccode`\!32 |
611 | \lowercase{% |
612 | \def\@isspaces#1{% |
613 | \ifx#1\relax% |
614 | \def\@tempb{\@tempswafalse}% |
615 | \else\ifx#1~% |
616 | \let\@tempb\@isspaces% |
617 | \else% |
618 | \def\@tempb##1\relax{}% |
619 | \fi\fi% |
620 | \@tempb% |
621 | } |
622 | \def\sv@safespc{% |
623 | \catcode32\active% |
624 | \def~{ }% |
625 | } |
626 | } |
627 | % \end{macrocode} |
628 | % |
629 | % \end{macro} |
630 | % |
631 | % \begin{macro}{\sv@read} |
632 | % |
633 | % This macro does the main job of reading a chunk of verbatim text. You call |
634 | % it like this: |
635 | % |
636 | % \begin{quote} |
637 | % \syntax{"\\sv@read{"<end-text>"}{"<process-line-proc>"}{"<end-proc>"}"} |
638 | % \end{quote} |
639 | % |
640 | % The \synt{end-text} is the text to find at the end of the `environment': we |
641 | % stop when we find it. |
642 | % |
643 | % The \synt{process-line-proc} is a macro which is passed as an argument each |
644 | % line which we read from the text. |
645 | % |
646 | % The \synt{end-proc} is a macro to call once we've finished reading all of |
647 | % the text. This can tidy up an environment or close a file or whatever. |
648 | % |
649 | % We read the text by picking out newlines using a delimited macro. We have |
650 | % to be a little clever, because newlines are active in verbatim text. |
651 | % |
652 | % We will also strip `|%|' signs off the beginning if the \package{doc} |
653 | % package is here (\package{doc} tries to play with \LaTeX's verbatim stuff, |
654 | % and doesn't understand the way we do things). |
655 | % |
656 | % \begin{macrocode} |
657 | \def\sv@read#1#2#3{% |
658 | % \end{macrocode} |
659 | % |
660 | % This code does all sorts of evil things, so I'll start by opening a group. |
661 | % |
662 | % \begin{macrocode} |
663 | \begingroup% |
664 | % \end{macrocode} |
665 | % |
666 | % So that I can spot the end-text, I'll create a matcher macro. |
667 | % |
668 | % \begin{macrocode} |
669 | \matcher\@match{#1}\sv@read@ii% |
670 | % \end{macrocode} |
671 | % |
672 | % So that I can identify line ends, I'll make them active. I'll also make |
673 | % spaces active so that they can expand to whatever they ought to expand |
674 | % to (spaces in files, or funny \verb*" " characters or whatever. |
675 | % |
676 | % \begin{macrocode} |
677 | \catcode13\active% |
678 | \catcode32\active% |
679 | % \end{macrocode} |
680 | % |
681 | % I'll use the |\if@tempswa| flag to tell me whether I ought to output the |
682 | % current line. This is a little messy, so I'll describe it later. I'll |
683 | % initialise it to false because this is the correct thing to do. |
684 | % |
685 | % \begin{macrocode} |
686 | \@tempswafalse% |
687 | % \end{macrocode} |
688 | % |
689 | % Most of the job is done by two submacros. I'll define them in terms of |
690 | % my current arguments (to save lots of token munging). The first just |
691 | % extracts the next line (which ends at the next newline character) and |
692 | % tries to match it. |
693 | % |
694 | % \begin{macrocode} |
695 | \lccode`\~13\lowercase{% |
696 | \def\sv@read@i##1~{\@match{##1}}% |
697 | }% |
698 | % \end{macrocode} |
699 | % |
700 | % The results of the match get passed here, along with the text of the |
701 | % line up to the matched text. |
702 | % |
703 | % \begin{macrocode} |
704 | \def\sv@read@ii##1{% |
705 | % \end{macrocode} |
706 | % |
707 | % The first job to do is to maybe strip off percent signs from the beginning, |
708 | % to keep \package{doc} happy. |
709 | % |
710 | % \begin{macrocode} |
711 | \sv@percent##1\relax\relax% |
712 | % \end{macrocode} |
713 | % |
714 | % Now I need to decide whether I ought to output this line. The method goes |
715 | % like this: if this is the first line (|\if@tempswa| is false) or the last |
716 | % (|\if@matched| is true), \emph{and} the text consists only of spaces, then |
717 | % I'll ignore it. |
718 | % |
719 | % The first thing to do is to notice the last line -- if |\if@matched| is |
720 | % true, then I'll make |\if@tempswa| false to make the first-line and |
721 | % last-line cases work the same way. |
722 | % |
723 | % \begin{macrocode} |
724 | \if@matched\@tempswafalse\fi% |
725 | % \end{macrocode} |
726 | % |
727 | % Now if this is the first or last line, I'll examine it for spaces. This |
728 | % is done in a separate macro. It will set |\if@tempswa| false if the |
729 | % text contains only spaces. |
730 | % |
731 | % \begin{macrocode} |
732 | \if@tempswa\else\@tempswatrue\expandafter\@isspaces\@tempa\relax\fi% |
733 | % \end{macrocode} |
734 | % |
735 | % Now, if |\if@tempswa| is still true, perform the \<process-line-proc> on |
736 | % the line of text. I'll provide a group, so that it doesn't upset me |
737 | % too much. |
738 | % |
739 | % \begin{macrocode} |
740 | \if@tempswa% |
741 | \begingroup% |
742 | \expandafter#2\expandafter{\@tempa}% |
743 | \endgroup% |
744 | \fi% |
745 | % \end{macrocode} |
746 | % |
747 | % The next line won't be the first one, so I'll set the flag true in |
748 | % readiness. |
749 | % |
750 | % \begin{macrocode} |
751 | \@tempswatrue% |
752 | % \end{macrocode} |
753 | % |
754 | % Now, if that wasn't the last line, go round again; otherwise end the group |
755 | % I started ages ago, and do the user's \<end-proc>. |
756 | % |
757 | % \begin{macrocode} |
758 | \if@matched\def\@tempa{\endgroup#3}\else\let\@tempa\sv@read@i\fi% |
759 | \@tempa% |
760 | }% |
761 | % \end{macrocode} |
762 | % |
763 | % Now to start the thing up. I'll read the first line. |
764 | % |
765 | % \begin{macrocode} |
766 | \sv@read@i% |
767 | } |
768 | % \end{macrocode} |
769 | % |
770 | % \end{macro} |
771 | % |
772 | % \begin{macro}{\sv@readenv} |
773 | % |
774 | % This macro works out an appropriate end-text for the current environment. |
775 | % If you say \syntax{"\\sv@readenv{"<macro-name>"}"}, it will expand do |
776 | % \begin{listinglist} \listingsize \synshorts |
777 | % <macro-name>"{\\"$_{12}$"end{"$_{12}$<current-env-name>"}"$_{12}$"}"^^A |
778 | % "{\\end{"<current-env-name>"}}" |
779 | % \end{listinglist} |
780 | % Easy, no? |
781 | % |
782 | % This is all done with mirrors. No, err\dots\ it's done with |
783 | % |\expandafter|. |
784 | % |
785 | % \begin{macrocode} |
786 | \begingroup |
787 | \lccode`\<=`\{ |
788 | \lccode`\>=`\} |
789 | \lccode`\|=`\\ |
790 | \lowercase{\endgroup |
791 | \def\sv@readenv#1{% |
792 | \expandafter\expandafter\expandafter% |
793 | #1\expandafter\sv@readenv@i\@currenvir\@@% |
794 | } |
795 | \def\sv@readenv@i#1\@@{{|end<#1>}{\end{#1}}} |
796 | } |
797 | % \end{macrocode} |
798 | % |
799 | % \end{macro} |
800 | % |
801 | % \begin{macro}{\sv@verbline} |
802 | % |
803 | % This macro typesets a line in a verbatim way, so you can construct a real |
804 | % verbatim environment from it. It's a bit tricky in the way that it catches |
805 | % the last line. Don't worry about this: it's easy really. Note the |
806 | % |\relax| after the |\par| -- this is because \package{doc} tries to do |
807 | % clever things with |\par| to strip `|%|' signs out. |
808 | % |
809 | % \begin{macrocode} |
810 | \def\sv@verbline#1{% |
811 | \setbox\z@\hbox{#1\sv@stripspc}% |
812 | \ifdim\wd\z@=\z@% |
813 | \if@matched\ifhmode\par\relax\fi\else\leavevmode\par\relax\fi% |
814 | \else% |
815 | \leavevmode\box\z@\par\relax% |
816 | \fi% |
817 | } |
818 | % \end{macrocode} |
819 | % |
820 | % \end{macro} |
821 | % |
822 | % \subsection{Listing environments} |
823 | % |
824 | % The \env{listing} environment is our equivalent of the standard |
825 | % \env{verbatim} environment. We do some slightly cleverer things, though, |
826 | % to make sure (for example) that even text which contains |\end{listing}| |
827 | % can be typeset. |
828 | % |
829 | % \begin{macro}{\listinglist} |
830 | % \begin{environment}{listinglist} |
831 | % |
832 | % This defines the layout for the \env{listing} environment. It starts a |
833 | % list with the appropriate shape. It's also made into an environment, so |
834 | % that the end-paragraph-environment bits work correctly. |
835 | % |
836 | % The |\listingindent| length parameter sets up the indentation of the |
837 | % listings. If there's a |\parindent| setting, I'll line listings up with |
838 | % that; otherwise I'll just choose something which looks right. |
839 | % |
840 | % \begin{macrocode} |
841 | \newdimen\listingindent |
842 | \AtBeginDocument{% |
843 | \ifdim\parindent=\z@\listingindent1em\else\listingindent\parindent\fi% |
844 | } |
845 | % \end{macrocode} |
846 | % |
847 | % Now to define a size hook for the environment. This is fairly simple |
848 | % stuff. |
849 | % |
850 | % \begin{macrocode} |
851 | \ifx\listingsize\@@undefined |
852 | \let\listingsize\small |
853 | \fi |
854 | % \end{macrocode} |
855 | % |
856 | % Now to define the environment itself. Suppress the indentation if we're |
857 | % first thing on a new list item, so that the listing lines up with |
858 | % everything else. |
859 | % |
860 | % \begin{macrocode} |
861 | \def\listinglist{% |
862 | \list{}{% |
863 | \if@inlabel% |
864 | \leftmargin\z@% |
865 | \else% |
866 | \leftmargin\listingindent% |
867 | \fi% |
868 | \rightmargin\z@% |
869 | \labelwidth\z@% |
870 | \labelsep\z@% |
871 | \itemindent\z@% |
872 | \listparindent\z@% |
873 | \let\makelabel\relax% |
874 | \parsep\z@skip% |
875 | }% |
876 | \parfillskip\@flushglue% |
877 | \item\relax% |
878 | } |
879 | \let\endlistinglist\endlist |
880 | % \end{macrocode} |
881 | % |
882 | % \end{environment} |
883 | % \end{macro} |
884 | % |
885 | % \begin{environment}{listing} |
886 | % |
887 | % The \env{listing} environment is the only real verbatim-like environment we |
888 | % create will all this kit, although it does the job very nicely. |
889 | % |
890 | % The environment indents its contents slightly, unlike \env{verbatim}, and |
891 | % uses a smaller typeface in an attempt to fit 77-column text on an A5~page. |
892 | % There is also a $*$-variant, which allows you to specify the terminating |
893 | % text. This enables you to include absolutely any text in the environment, |
894 | % including |\end{listing}|. |
895 | % |
896 | % First, we must define the |\listing| command. |
897 | % |
898 | % \begin{macrocode} |
899 | \def\listing{% |
900 | \listinglist% |
901 | \listingsize% |
902 | \sv@readenv\sv@listing% |
903 | } |
904 | % \end{macrocode} |
905 | % |
906 | % Now we define the |\@listing| command, which does most of the work. We |
907 | % base the \env{listing} environment on a \env{list}. |
908 | % |
909 | % \begin{macrocode} |
910 | \def\sv@listing#1#2{% |
911 | \sv@startlisting% |
912 | \sv@read{#1}\sv@verbline{\endlistinglist#2}% |
913 | } |
914 | % \end{macrocode} |
915 | % |
916 | % Now we define the starred version. The command name needs to include the |
917 | % `|*|' character, so we must use |\csname|. There's some hacking here to |
918 | % allow us to read the name using the appropriate catcodes for otherwise |
919 | % normal characters: \LaTeX\ activates some characters and makes them typeset |
920 | % themselves to suppress some ligaturing. |
921 | % |
922 | % \begin{macrocode} |
923 | \expandafter\def\csname listing*\endcsname{% |
924 | \listinglist% |
925 | \listingsize% |
926 | \begingroup% |
927 | \@noligs% |
928 | \def\@tempa##1{\endgroup\sv@listing{##1}{\end{listing*}}}% |
929 | \@tempa% |
930 | } |
931 | % \end{macrocode} |
932 | % |
933 | % \end{environment} |
934 | % |
935 | % \begin{environment}{ignore} |
936 | % |
937 | % The \env{ignore} environment entirely ignores its contents. Anything at |
938 | % all may be put into the environment: it is discarded utterly. |
939 | % |
940 | % We define some macros for defining ignoring environments, because this can |
941 | % be useful for version control, possibly. |
942 | % |
943 | % \begin{macrocode} |
944 | \def\sv@ignore#1#2{% |
945 | \@bsphack% |
946 | \let\do\@makeother\dospecials% |
947 | \sv@read{#1}\@gobble{\@esphack#2}% |
948 | } |
949 | \def\ignore{\sv@readenv\sv@ignore} |
950 | \def\ignoreenv#1{% |
951 | \expandafter\let\csname #1\endcsname\ignore% |
952 | } |
953 | \def\unignoreenv#1{% |
954 | \expandafter\def\csname #1\endcsname{\endgroup}% |
955 | \expandafter\def\csname end#1\endcsname% |
956 | {\begingroup\def\@currenvir{#1}}% |
957 | } |
958 | % \end{macrocode} |
959 | % |
960 | % \end{environment} |
961 | % |
962 | % \subsection{The \env{verbwrite} environment} |
963 | % |
964 | % The \env{verbwrite} environment allows text to be written to a file in a |
965 | % verbatim way. Note that tab characters don't work, because \TeX\ refuses |
966 | % to be nice. |
967 | % |
968 | % \begin{macro}{\sv@write} |
969 | % |
970 | % As seems to be traditional now, we first define a general hookable macro |
971 | % which allows a caller to specify the end-text and what to do afterwards. |
972 | % |
973 | % \begin{macrocode} |
974 | \newwrite\sv@writefile |
975 | \def\sv@write#1#2{% |
976 | \begingroup% |
977 | \@bsphack% |
978 | \let\do\@makeother\dospecials% |
979 | \sv@safespc% |
980 | \sv@read{#1}\sv@writeline{\sv@endwrite#2}% |
981 | } |
982 | \def\sv@writeline#1{% |
983 | \immediate\write\sv@writefile{#1}% |
984 | } |
985 | \def\sv@endwrite{% |
986 | \@esphack% |
987 | \endgroup% |
988 | } |
989 | % \end{macrocode} |
990 | % |
991 | % \end{macro} |
992 | % |
993 | % \begin{environment}{verbwrite} |
994 | % |
995 | % Now we can define the actual environment. We define a $*$-variant which |
996 | % allows the user to specify the end-text, just to make sure. |
997 | % |
998 | % \begin{macrocode} |
999 | \def\verbwrite#1{% |
1000 | \immediate\openout\sv@writefile#1\relax% |
1001 | \sv@readenv\sv@write% |
1002 | } |
1003 | \def\endverbwrite{\immediate\closeout\sv@writefile} |
1004 | \expandafter\def\csname verbwrite*\endcsname#1#2{% |
1005 | \immediate\openout\sv@writefile#2\relax% |
1006 | \sv@write{#1}{\immediate\closeout\sv@writefile\end{verbwrite*}}% |
1007 | } |
1008 | % \end{macrocode} |
1009 | % |
1010 | % \end{environment} |
1011 | % |
1012 | % \subsection{The \env{demo} environment} |
1013 | % |
1014 | % By way of tying all of this together, I present an environment for |
1015 | % displaying demonstrations of \LaTeX\ markup. We read the contents of the |
1016 | % environment, write it to a temporary file, and read it back twice, |
1017 | % typesetting it the first time and displaying it verbatim the second time. |
1018 | % |
1019 | % \begin{macro}{\sv@demoname} |
1020 | % |
1021 | % This macro expands to the filename to use for the temporary data. To |
1022 | % allow the package documentation to demonstrate the \env{demo} environment |
1023 | % itself, we need to keep a nesting count. This avoids too much hackery, |
1024 | % which unfortunately appears to plague all of my \TeX\ code. |
1025 | % |
1026 | % \begin{macrocode} |
1027 | \newcount\sv@nestcount |
1028 | \def\sv@demoname{demo\number\sv@nestcount.tmp} |
1029 | % \end{macrocode} |
1030 | % |
1031 | % \end{macro} |
1032 | % |
1033 | % \begin{macro}{\sv@demo} |
1034 | % |
1035 | % As for listing, we do all the business through a private macro. This is |
1036 | % good because it means we can leave the main macro readable. The argument |
1037 | % is the end-text to spot. |
1038 | % |
1039 | % \begin{macrocode} |
1040 | \def\sv@demo#1#2{% |
1041 | \@ifnextchar[{\sv@demo@i{#1}{#2}}{\sv@demo@i{#1}{#2}[n]}% |
1042 | } |
1043 | \def\sv@demo@i#1#2[#3]#4{% |
1044 | \advance\sv@nestcount by\@ne% |
1045 | \immediate\openout\sv@writefile\sv@demoname\relax% |
1046 | \sv@write{#1}{% |
1047 | \immediate\closeout\sv@writefile% |
1048 | \sv@dodemo{#2}{#3}{#4}% |
1049 | }% |
1050 | } |
1051 | % \end{macrocode} |
1052 | % |
1053 | % \end{macro} |
1054 | % |
1055 | % \begin{environment}{demo} |
1056 | % |
1057 | % This is the real environment. We provide \env{demo$*$} too, to allow the |
1058 | % user to choose the end-text. |
1059 | % |
1060 | % \begin{macrocode} |
1061 | \def\demo{\sv@readenv\sv@demo} |
1062 | \expandafter\def\csname demo*\endcsname#1{\sv@demo{#1}{\end{demo*}}} |
1063 | % \end{macrocode} |
1064 | % |
1065 | % \end{environment} |
1066 | % |
1067 | % \begin{macro}{\sv@dodemo} |
1068 | % |
1069 | % First, let's define some common bits of code in the stuff below. The |
1070 | % minipages used to typeset the material has some clever stuff to avoid |
1071 | % strange spacing in the output. |
1072 | % |
1073 | % \begin{macrocode} |
1074 | \def\sv@demosmp{% |
1075 | \begin{minipage}[t]{\@tempdima}% |
1076 | \vskip8\p@% |
1077 | \hrule\@height\z@% |
1078 | \raggedright% |
1079 | \vbox\bgroup% |
1080 | } |
1081 | \def\sv@demoemp{% |
1082 | \par\unpenalty\unskip% |
1083 | \egroup% |
1084 | \vskip8\p@% |
1085 | \hrule\@height\z@% |
1086 | \end{minipage}% |
1087 | } |
1088 | % \end{macrocode} |
1089 | % |
1090 | % This is the macro which actually typesets the demonstration. |
1091 | % |
1092 | % \begin{macrocode} |
1093 | \def\sv@dodemo#1#2#3{% |
1094 | % \end{macrocode} |
1095 | % |
1096 | % Now work out some values. We set |\hsize| to the line width leaving 2\,em |
1097 | % of space on either side. The size of the minipages is calculated depending |
1098 | % on the shape of the demonstration. This is all fairly simple. |
1099 | % |
1100 | % \begin{macrocode} |
1101 | \begingroup% |
1102 | \@tempdima\linewidth% |
1103 | \advance\@tempdima-2em% |
1104 | \hsize\@tempdima% |
1105 | \if#2w% |
1106 | \advance\@tempdima-2em% |
1107 | \else% |
1108 | \advance\@tempdima-3em% |
1109 | \divide\@tempdima2% |
1110 | \fi% |
1111 | % \end{macrocode} |
1112 | % |
1113 | % Now we open a big vertical box, and put in a header to mark off the |
1114 | % demonstration. |
1115 | % |
1116 | % \begin{macrocode} |
1117 | \par% |
1118 | \setbox\z@\hbox{\strut\enspace#3\enspace\strut}% |
1119 | \@tempdimb.5\dp\z@% |
1120 | \advance\@tempdimb-.5\ht\z@% |
1121 | \ht\z@\@tempdimb\dp\z@\@tempdimb% |
1122 | \noindent\hskip1em\vtop{% |
1123 | \hb@xt@\hsize{% |
1124 | \hrulefill% |
1125 | \raise\@tempdimb\box\z@% |
1126 | \hrulefill% |
1127 | }% |
1128 | \nointerlineskip% |
1129 | \hb@xt@\hsize{\vrule\@height5\p@\hfil\vrule\@height5\p@}% |
1130 | \nointerlineskip% |
1131 | % \end{macrocode} |
1132 | % |
1133 | % Now we insert the output text in the first minipage. I'll force `|%|' |
1134 | % to be a comment character, in case something like \package{doc} has had its |
1135 | % wicked way. |
1136 | % |
1137 | % \begin{macrocode} |
1138 | \vskip-\parskip% |
1139 | \noindent\hbox{}\hskip1em% |
1140 | \sv@demosmp% |
1141 | \catcode`\%14\relax% |
1142 | \input{\sv@demoname}% |
1143 | \sv@demoemp% |
1144 | % \end{macrocode} |
1145 | % |
1146 | % Insert some kind of separation between the two. In `wide' format, we start |
1147 | % a new line, and put a ruleoff between the two. In `narrow' format, we just |
1148 | % leave some space. |
1149 | % |
1150 | % \begin{macrocode} |
1151 | \if#2w% |
1152 | \vskip8\p@\hrule\vskip8\p@% |
1153 | \noindent\hbox{}% |
1154 | \fi% |
1155 | \hskip1em% |
1156 | % \end{macrocode} |
1157 | % |
1158 | % Now we put the verbatim copy of the text in the other minipage. |
1159 | % |
1160 | % \begin{macrocode} |
1161 | \sv@demosmp% |
1162 | \listingindent\z@% |
1163 | \verbinput\sv@demoname% |
1164 | \sv@demoemp% |
1165 | \par% |
1166 | \nointerlineskip% |
1167 | \hb@xt@\hsize{\vrule\@height5\p@\hfil\vrule\@height5\p@}% |
1168 | \hrule% |
1169 | }% |
1170 | \endgroup% |
1171 | \par% |
1172 | \vskip\baselineskip% |
1173 | #1% |
1174 | } |
1175 | % \end{macrocode} |
1176 | % |
1177 | % \end{macro} |
1178 | % |
1179 | % That's all there is. Have fun. |
1180 | % |
1181 | % \begin{macrocode} |
1182 | %</package> |
1183 | % \end{macrocode} |
1184 | % |
1185 | % \hfill Mark Wooding, \today |
1186 | % |
1187 | % \Finale |
1188 | % |
1189 | \endinput |