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1 | % \begin{meta-comment} |
2 | % |
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3 | % $Id: exercise.dtx,v 1.2 2003/09/05 16:10:41 mdw Exp $ |
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4 | % |
5 | % Exercises |
6 | % |
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7 | % (c) 2003 Mark Wooding |
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8 | % |
9 | %----- Revision history ----------------------------------------------------- |
10 | % |
11 | % $Log: exercise.dtx,v $ |
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12 | % Revision 1.2 2003/09/05 16:10:41 mdw |
13 | % Non-typesetting of answers. Reading in answers from another document. |
14 | % |
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15 | % Revision 1.1 2002/02/03 20:49:03 mdw |
16 | % Checkin for new build system. |
17 | % |
18 | % |
19 | % \end{meta-comment} |
20 | % |
21 | % \begin{meta-comment} <general public licence> |
22 | %% |
23 | %% exercise package -- useful macros for setting exercises with answers |
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24 | %% Copyright (c) 2003 Mark Wooding |
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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 Foundation, |
38 | %% Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
39 | % \end{meta-comment} |
40 | % |
41 | % \begin{meta-comment} <Package preambles> |
42 | %<+package>\NeedsTeXFormat{LaTeX2e} |
43 | %<+package>\ProvidesPackage{exercise} |
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44 | %<+package> [2003/08/25 1.1 Exercies with answers] |
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45 | % \end{meta-comment} |
46 | % |
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47 | % \CheckSum{271} |
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48 | %% \CharacterTable |
49 | %% {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 |
50 | %% 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 |
51 | %% Digits \0\1\2\3\4\5\6\7\8\9 |
52 | %% Exclamation \! Double quote \" Hash (number) \# |
53 | %% Dollar \$ Percent \% Ampersand \& |
54 | %% Acute accent \' Left paren \( Right paren \) |
55 | %% Asterisk \* Plus \+ Comma \, |
56 | %% Minus \- Point \. Solidus \/ |
57 | %% Colon \: Semicolon \; Less than \< |
58 | %% Equals \= Greater than \> Question mark \? |
59 | %% Commercial at \@ Left bracket \[ Backslash \\ |
60 | %% Right bracket \] Circumflex \^ Underscore \_ |
61 | %% Grave accent \` Left brace \{ Vertical bar \| |
62 | %% Right brace \} Tilde \~} |
63 | %% |
64 | % |
65 | % \begin{meta-comment} |
66 | % |
67 | %<*driver> |
68 | \input{mdwtools} |
69 | \describespackage{exercise} |
70 | \let\epsilon\varepsilon |
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71 | \errorcontextlines\maxdimen |
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72 | \mdwdoc |
73 | %</driver> |
74 | % |
75 | % \end{meta-comment} |
76 | % |
77 | %^^A------------------------------------------------------------------------- |
78 | % \section{User guide} |
79 | % |
80 | % The \package{exercise} package allows you to typeset exercises and keep the |
81 | % answers together with the questions in your source (so they don't get |
82 | % lost) but typeset them all together at the end of your document. |
83 | % |
84 | % \subsection{Exercises and answers} |
85 | % |
86 | % \DescribeEnv{exercise} |
87 | % Exercises are typset in an \env{exercise} environment. This takes no |
88 | % arguments. There's a counter for exercises, named |exercise|, and you can |
89 | % cross-reference exercises in the usual way. |
90 | % |
91 | % \DescribeMacro\answer |
92 | % If you want to include an answer for your exercise, just say |\answer| |
93 | % followed by your answer. The rest of the text up to the end of the |
94 | % \env{exercise} environment is considered to be the answer, and is stored |
95 | % away until asked for. This material can contain anything you like. It |
96 | % \emph{isn't} a moving argument. |
97 | % |
98 | % \begin{figure} |
99 | %\begin{demo}[w]{The \env{exercise} environment} |
100 | %\begin{exercise} |
101 | %Show that if $F\colon \{0, 1\}^k \times \{0, 1\}^* \to \{0, 1\}^L$ |
102 | %is a $(t, q + 1, \epsilon)$-secure PRF, then $F$~is also a |
103 | %$(t, q, \epsilon + 2^{-L})$-secure MAC. |
104 | %\answer |
105 | %Let~$A$ be an adversary attacking~$F$ as a MAC. Consider the |
106 | %adversary~$B$ \ldots |
107 | %\end{exercise} |
108 | %\end{demo} |
109 | % \end{figure} |
110 | % |
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111 | % \DescribeMacro\skipanswer |
112 | % The |\skipanswer| command is similar, but just skips over the answer rather |
113 | % than writing it to the output file. It does nothing at all with counters |
114 | % -- it's as if there was no answer given at all. |
115 | % |
116 | % It's OK to use commands like |\answer| and |\skipanswer| in your own |
117 | % macros as long as they're the \emph{last} token. You can therefore say |
118 | % something like |
119 | %\begin{verbatim} |
120 | %\newcommand{\evenanswer}{% |
121 | % \ifthenelse% |
122 | % {\isodd{\value{exercise}}}% |
123 | % {\answer}% |
124 | % {\skipanswer}% |
125 | %} |
126 | %\end{verbatim} |
127 | % to get just the answers to the odd-numbered problems. (If you don't like |
128 | % \package{ifthen} then you'll need to play with |\expandafter| for a bit.) |
129 | % |
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130 | % \subsection{The answers file} |
131 | % |
132 | % \DescribeMacro\answrite |
133 | % Answers are accumulated into a file, to be read later. Additional material |
134 | % can be added to the file using the |\answrite| macro, which just writes its |
135 | % argument. Note that this is a \emph{moving} argument, so fragile commands |
136 | % need |\protect|ing. |
137 | % |
138 | % \DescribeMacro\exctrcheck |
139 | % It's common to divide up the answers by section. You can tell the package |
140 | % to check a collection of counters and perform actions if they've changed |
141 | % since last time, giving you a chance to write the correct decorations to |
142 | % the answers file. This is done by saying |
143 | % \syntax{"\\exctrcheck{"<counter>"}{"<action>"}"}. Then, each |\answer| |
144 | % command checks to see if \<counter> has changed since last time, and if it |
145 | % has, it does \<action>, For example, |
146 | %\begin{verbatim} |
147 | %\exctrcheck{section} |
148 | % {\answrite{\protect\subsection*{Section \thesection}}} |
149 | %\end{verbatim} |
150 | % starts a new (unnumbered) subsection in the answers for each section in the |
151 | % main document. |
152 | % |
153 | % \subsection{Style tweaks} |
154 | % |
155 | % The \env{exercise} environment is very simple, and can be easily rewritten |
156 | % to fit in with your style preferences. If you like exercises to look like |
157 | % theorems, the easiest thing to do is say something like |
158 | %\begin{verbatim} |
159 | %\newtheorem{doexercise}[exercise]{\exercisename} |
160 | %\renewenvironment{exercise}{\exfix\doexercise}{\enddoexercise} |
161 | %\end{verbatim} |
162 | % This makes the environment use the existing exercise counter. If you don't |
163 | % want that, say |
164 | %\begin{verbatim} |
165 | %\newtheorem{doexercise}[othercounter]{\exercisename} |
166 | %\renewenvironment{exercise}{\exfix\doexercise}{\enddoexercise} |
167 | %\let\theexercise\theothercounter |
168 | %\end{verbatim} |
169 | % and all will be well. |
170 | % |
171 | % \DescribeEnv{doanswer} |
172 | % Answers are typeset in a \env{doanswer} environment, which is given one |
173 | % argument: the exercise number (as set by |\theexercise|). This can be |
174 | % modified to do whatever you like. |
175 | % |
176 | % \DescribeMacro\exfix |
177 | % The |\exfix| is a convenient hook which is run both in the \env{exercise} |
178 | % and \env{doanswer} environments by default. The current implementation |
179 | % just skips a level of \env{enumerate} depth, which usually means that |
180 | % \env{enumerate} lists will go (a), (b), (c), \ldots\ rather than 1, 2, 3, |
181 | % \ldots |
182 | % |
183 | % \subsection{Lists in paragraphs} |
184 | % |
185 | % \DescribeEnv{parenum} |
186 | % Answers to subparts tend to be compressed together into a single |
187 | % paragraph. It's nice, when you do this, not to have to worry about losing |
188 | % your numbering of subparts. The \env{parenum} environment provides an |
189 | % enumerated list in a paragraph. So, for example, you can say something |
190 | % like this. |
191 | %\begin{demo}[w]{Example of \env{parenum}} |
192 | %\begin{exercise} |
193 | %A PRG $g\colon \{0, 1\}^k \to \{0, 1\}^L$ is \emph{trivial} if |
194 | %$k \ge L$. |
195 | %\begin{enumerate} |
196 | %\item Show that trivial PRGs exist. |
197 | %\item Show that a non-trivial $(t, \epsilon)$-secure PRG is a |
198 | % $(t, \epsilon + 2^{k-L})$-secure one-way function. |
199 | %\end{enumerate} |
200 | %\answer |
201 | %\begin{parenum} |
202 | %\item The identity function is a trivial PRG: the real and random |
203 | % games are identically distributed. |
204 | %\item Let~$A$ be an adversary attempting to invert~$g$: then we |
205 | % can construct a distinguisher~$B$ as follows \ldots |
206 | %\end{parenum} |
207 | %\end{exercise} |
208 | %\end{demo} |
209 | % |
210 | % \subsection{And finally} |
211 | % |
212 | % \DescribeMacro\answers |
213 | % In order to extract your answers, say |\answers|. |
214 | %\begin{demo}[w]{The \texttt{\string\answers} command} |
215 | %\section*{Answers} |
216 | %\answers |
217 | %\end{demo} |
218 | % |
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219 | % The |\answers| command has an optional argument, which is the file to read |
220 | % in. This allows you to make `answer booklet' documents, by saying |
221 | % something like |
222 | %\begin{verbatim} |
223 | %\answers[otherdoc] |
224 | %\end{verbatim} |
225 | % If you don't give a file extension, then |.ans| is appended automatically. |
226 | % |
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227 | % \implementation |
228 | % |
229 | % |
230 | %^^A------------------------------------------------------------------------- |
231 | % \section{Implementation} |
232 | % |
233 | % \begin{macrocode} |
234 | %<*package> |
235 | % \end{macrocode} |
236 | % |
237 | % \subsection{Initialization} |
238 | % |
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239 | % The \textsf{within} option is handled by the \package{mdwkey} package. |
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240 | % |
241 | % \begin{macrocode} |
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242 | \RequirePackage{mdwkey} |
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243 | % \end{macrocode} |
244 | % |
245 | % \begin{macro}{\ex@within} |
246 | % |
247 | % When the \textsf{within} option is seen, we set a command |\ex@within| to |
248 | % the correct code, to be executed later when we've made our minds up. |
249 | % |
250 | % \begin{macrocode} |
251 | \let\ex@within\relax |
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252 | \mkdef{exercise:opts}{within}{% |
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253 | \def\ex@within{% |
254 | \@addtoreset{exercise}{#1}% |
255 | \toks@\expandafter{\csname the#1\expandafter\endcsname% |
256 | \expandafter.\theexercise}% |
257 | \edef\theexercise{\the\toks@}% |
258 | }% |
259 | } |
260 | % \end{macrocode} |
261 | % \end{macro} |
262 | % |
263 | % \begin{macro}{\ex@opts} |
264 | % |
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265 | % The |\ex@opts| macro just runs the \package{mdwkey} kit to parse an option |
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266 | % string. |
267 | % |
268 | % \begin{macrocode} |
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269 | \def\ex@opts{\mkparse{exercise:opts}} |
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270 | % \end{macrocode} |
271 | % \end{macro} |
272 | % |
273 | % Now do the options thing. |
274 | % |
275 | % \begin{macrocode} |
276 | \DeclareOption*{\expandafter\ex@opts\expandafter{\CurrentOption}} |
277 | \ProcessOptions* |
278 | % \end{macrocode} |
279 | % |
280 | % Set up the |exercise| counter, and number it within some other sort of |
281 | % counter as appropriate. |
282 | % |
283 | % \begin{macrocode} |
284 | \newcounter{exercise}\ex@within |
285 | % \end{macrocode} |
286 | % |
287 | % We also need the \package{sverb} package in order to do the delaying of the |
288 | % answers. |
289 | % |
290 | % \begin{macrocode} |
291 | \RequirePackage{sverb} |
292 | % \end{macrocode} |
293 | % |
294 | % \subsection{Checking for counter changes} |
295 | % |
296 | % \begin{macro}{\ex@ctrcheck} |
297 | % |
298 | % The counter checking state is stored here. It's initially empty. |
299 | % |
300 | % \begin{macrocode} |
301 | \def\ex@ctrcheck{} |
302 | % \end{macrocode} |
303 | % \end{macro} |
304 | % |
305 | % \begin{macro}{\exctrcheck} |
306 | % |
307 | % Adding a counter to the check list is relatively easy. We expand the |
308 | % current list into a token register, add the new material to the end, and |
309 | % put the list back in our macro using |\edef|. The `last' value of the |
310 | % counter is set to |\relax|, to force out the change on the next |\answer|. |
311 | % |
312 | % \begin{macrocode} |
313 | \def\exctrcheck#1#2{% |
314 | \toks@\expandafter{\ex@ctrcheck\ex@ctrdo{#1}{#2}}% |
315 | \edef\ex@ctrcheck{\the\toks@}% |
316 | \global\expandafter\let\csname ex@ctrlast@#1\endcsname\relax% |
317 | } |
318 | % \end{macrocode} |
319 | % \end{macro} |
320 | % |
321 | % \begin{macro}{\ex@ctrdo} |
322 | % |
323 | % Here we actually check to see whether a counter has changed and execute the |
324 | % appropriate code. |
325 | % |
326 | % \begin{macrocode} |
327 | \def\ex@ctrdo#1#2{% |
328 | \edef\@tempa{\csname the#1\endcsname}% |
329 | \expandafter\ifx\csname ex@ctrlast@#1\endcsname\@tempa\else% |
330 | #2% |
331 | \global\expandafter\let\csname ex@ctrlast@#1\endcsname\@tempa% |
332 | \fi% |
333 | } |
334 | % \end{macrocode} |
335 | % \end{macro} |
336 | % |
337 | % \subsection{The \env{exercise} environment} |
338 | % |
339 | % \begin{macro}{\exercisename} |
340 | % |
341 | % We store the string to print for each exercise in |\exercisename| as a |
342 | % half-hearted attempt at internationalization. |
343 | % |
344 | % \begin{macrocode} |
345 | \providecommand\exercisename{Exercise} |
346 | % \end{macrocode} |
347 | % \end{macro} |
348 | % |
349 | % \begin{macro}{\exfix} |
350 | % |
351 | % This is a dumping ground for style fixing common to both exercises and |
352 | % answers. Here, we bump on the \env{enum} depth counter, so that it skips |
353 | % labelling with digits. |
354 | % |
355 | % \begin{macrocode} |
356 | \def\exfix{\advance\@enumdepth\@ne} |
357 | % \end{macrocode} |
358 | % \end{macro} |
359 | % |
360 | % \begin{environment}{exercise} |
361 | % |
362 | % This is pretty simple. The environment is list-based, with the number set |
363 | % in bold in a label. |
364 | % |
365 | % \begin{macrocode} |
366 | \def\exercise{% |
367 | \refstepcounter{exercise}% |
368 | \exfix% |
369 | \trivlist\advance\itemindent\labelsep% |
370 | \item[\textbf{\exercisename\ \theexercise}]% |
371 | } |
372 | \let\endexercise\endtrivlist |
373 | % \end{macrocode} |
374 | % \end{environment} |
375 | % |
376 | % \subsection{Answers} |
377 | % |
378 | % We need a file in which to store our answers. |
379 | % |
380 | % \begin{macrocode} |
381 | \newwrite\ex@ansfile |
382 | % \end{macrocode} |
383 | % |
384 | % \begin{macro}{\ex@ansfilename} |
385 | % |
386 | % In case anyone has a better idea for a filename than our default, we |
387 | % provide a hook. |
388 | % |
389 | % \begin{macrocode} |
390 | \def\ex@ansfilename{\jobname.ans} |
391 | % \end{macrocode} |
392 | % \end{macro} |
393 | % |
394 | % We open the file at the end of the preamble, to give the user a chance to |
395 | % say |\nofiles|, or change |\ex@ansfilename|. |
396 | % |
397 | % \begin{macrocode} |
398 | \AtBeginDocument{% |
399 | \if@filesw% |
400 | \immediate\openout\ex@ansfile=\ex@ansfilename\relax% |
401 | \answrite\relax% |
402 | \fi% |
403 | } |
404 | % \end{macrocode} |
405 | % |
406 | % \begin{macro}{\answrite} |
407 | % |
408 | % This writes stuff to the answers file. We make sure that it's |
409 | % appropriately protected, so that you can insert section headings and so on. |
410 | % |
411 | % \begin{macrocode} |
412 | \def\answrite#1{% |
413 | \if@filesw% |
414 | \begingroup% |
415 | \let\protect\@unexpandable@protect% |
416 | \immediate\write\ex@ansfile{#1}% |
417 | \endgroup% |
418 | \fi% |
419 | } |
420 | % \end{macrocode} |
421 | % \end{macro} |
422 | % |
423 | % \begin{macro}{\answer} |
424 | % |
425 | % The |\answer| macro needs to read until the end of the enclosing |
426 | % \env{exercise} environment (or whatever). |
427 | % |
428 | % \begin{macrocode} |
429 | \def\answer{\sv@readenv\ex@answer} |
430 | % \end{macrocode} |
431 | % |
432 | % Now for the main guts. |
433 | % |
434 | % \begin{macrocode} |
435 | \def\ex@answer#1#2{% |
436 | \begingroup% |
437 | \@bsphack% |
438 | % \end{macrocode} |
439 | % |
440 | % First of all, check to see whether any counters have changed. |
441 | % |
442 | % \begin{macrocode} |
443 | \ex@ctrcheck% |
444 | % \end{macrocode} |
445 | % |
446 | % Start a \env{doanswer} environment in the file. |
447 | % |
448 | % \begin{macrocode} |
449 | \answrite{\noexpand\begin{doanswer}{\theexercise}}% |
450 | % \end{macrocode} |
451 | % |
452 | % Set catcodes to be strange, and read lines one-at-a-time, writing them to |
453 | % the file. When finished, continue at |\ex@endanswer|. |
454 | % |
455 | % \begin{macrocode} |
456 | \let\do\@makeother\dospecials% |
457 | \sv@safespc% |
458 | \sv@read{#1}\answrite{\ex@endanswer#2}% |
459 | } |
460 | % \end{macrocode} |
461 | % |
462 | % When that's done, we wind up here. |
463 | % |
464 | % \begin{macrocode} |
465 | \def\ex@endanswer{% |
466 | \@esphack% |
467 | \answrite{\noexpand\end{doanswer}}% |
468 | \endgroup% |
469 | } |
470 | % \end{macrocode} |
471 | % \end{macro} |
472 | % |
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473 | % \begin{macro}{\skipanswer} |
474 | % |
475 | % This is much simpler. |
476 | % |
477 | % \begin{macrocode} |
478 | \let\skipanswer\ignore |
479 | % \end{macrocode} |
480 | % \end{macro} |
481 | % |
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482 | % \begin{macro}{\answers} |
483 | % |
484 | % The |\answers| macro closes the file, makes sure that future |
485 | % \env{exercise}s with answers cause an error, and reads in the file. |
486 | % |
487 | % \begin{macrocode} |
488 | \def\answers{% |
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489 | \@ifnextchar[{\answers@i\input}{\answers@i\@input[\ex@ansfilename]}% |
490 | } |
491 | \def\answers@i#1[#2]{% |
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492 | \immediate\closeout\ex@ansfile% |
493 | \global\let\answrite\exerr@toolate% |
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494 | \ex@withext{#1}{#2}{ans}% |
495 | } |
496 | \def\q@delim{\q@delim} |
497 | \def\ex@withext#1#2#3{% |
498 | \edef\next@##1{\noexpand\ex@ext@i{##1}{#2}{#3}#2.\noexpand\q@delim}% |
499 | \next@{#1}% |
500 | } |
501 | \def\ex@ext@i#1#2#3#4.#5\q@delim{% |
502 | \ifx\q@delim#5\q@delim\def\next@{#1{#2.#3}}% |
503 | \else\def\next@{#1{#2}}\fi% |
504 | \next@% |
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505 | } |
506 | % \end{macrocode} |
507 | % \end{macro} |
508 | % |
509 | % \begin{environment}{doanswer} |
510 | % |
511 | % A very simple environment. We set the exercise number in bold and then |
512 | % just write the text. |
513 | % |
514 | % \begin{macrocode} |
515 | \def\doanswer#1{% |
516 | \exfix% |
517 | \trivlist\advance\itemindent\labelsep% |
518 | \item[\textbf{#1}]% |
519 | } |
520 | \let\enddoanswer\endtrivlist |
521 | % \end{macrocode} |
522 | % \end{environment} |
523 | % |
524 | % \subsection{Lists inside paragraphs} |
525 | % |
526 | % \begin{environment}{parlist} |
527 | % |
528 | % The \env{parlist} environment is a trimmed-down version of a normal list. |
529 | % We todge the |\item| command, make |\list| and |\trivlist| make errors, and |
530 | % do various normal list things. |
531 | % |
532 | % \begin{macrocode} |
533 | \def\parlist#1#2{% |
534 | \let\@trivlist\exerr@parlist% |
535 | \def\@itemlabel{#1}% |
536 | \let\makelabel\relax% |
537 | \@nmbrlistfalse% |
538 | #2% |
539 | \let\item\pl@item% |
540 | \ignorespaces% |
541 | } |
542 | % \end{macrocode} |
543 | % \end{environment} |
544 | % |
545 | % \begin{macro}{\pl@item} |
546 | % |
547 | % This is the implementation of |\item| within a \env{parlist}. The main |
548 | % interesting point is the game with boxes, which has the objective of |
549 | % extracting the text of the item, together with any style changes set by |
550 | % |\makelabel|, but without any stupid bits of glue, or |\llap| or anything |
551 | % like that. |
552 | % |
553 | % \begin{macrocode} |
554 | \def\pl@item{\@ifnextchar[\pl@item@i{\pl@item@i[\@itemlabel]}} |
555 | \def\pl@item@i[#1]{% |
556 | \if@nmbrlist\refstepcounter{\@listctr}\fi% |
557 | \setbox\z@\hbox{\makelabel{\global\setbox\@ne\hbox{#1}}}% |
558 | \ifvmode\leavevmode\else\unskip\hskip1em\fi\box\@ne~\ignorespaces% |
559 | } |
560 | % \end{macrocode} |
561 | % \end{macro} |
562 | % |
563 | % \begin{macro}{\useparlist} |
564 | % |
565 | % We just set the \env{list} environment to use \env{parlist}. |
566 | % |
567 | % \begin{macrocode} |
568 | \def\useparlist{\let\list\parlist\let\endlist\relax} |
569 | % \end{macrocode} |
570 | % \end{macro} |
571 | % |
572 | % \begin{environment}{parenum} |
573 | % |
574 | % Very simple, this. Note that we don't run |\endenumerate|, because that's |
575 | % |\let| to |\endlist|. |
576 | % |
577 | % \begin{macrocode} |
578 | \def\parenum{\useparlist\enumerate} |
579 | \let\endparenum\endparlist |
580 | % \end{macrocode} |
581 | % \end{environment} |
582 | % |
583 | % \subsection{Errors} |
584 | % |
585 | % \begin{macrocode} |
586 | \def\exerr@toolate{% |
587 | \PackageError{exercise}{Too late now for \string\answrite}{% |
588 | You can't write answers after you've read the file in. I've^^J% |
589 | ignored the text you attempted to write. This is why answers^^J% |
590 | go at the end of a book!% |
591 | }% |
592 | } |
593 | \def\exerr@parlist{% |
594 | \PackageError{exercise}{You can't nest a `list' inside a `parlist'.}{% |
595 | I've found a `list' or `trivlist' environment nested inside^^J% |
db127fce |
596 | a `parlist'. This isn't allowed. You're probably doomed now.% |
86f6a31e |
597 | }% |
598 | } |
599 | %</package> |
600 | % \end{macrocode} |
601 | % |
602 | % Done. |
603 | % |
604 | % \hfill Mark Wooding, \today |
605 | % |
606 | % \Finale |
607 | % |
608 | \endinput |