| 1 | % \begin{meta-comment} |
| 2 | % |
| 3 | % poetry.dtx |
| 4 | % |
| 5 | % Sophisticated typesetting of poetry |
| 6 | % |
| 7 | % (c) 1996 Mark Wooding |
| 8 | % |
| 9 | % \end{meta-comment} |
| 10 | % |
| 11 | % \begin{meta-comment} <general public licence> |
| 12 | %% |
| 13 | %% poetry package -- sophisticated typesetting of poetry |
| 14 | %% Copyright (c) 1996 Mark Wooding |
| 15 | %% |
| 16 | %% This package is not finished, let alone properly tested. It is being |
| 17 | %% released in the hope that others can contribute ideas and suggestions |
| 18 | %% that the author (who is not an expert on poetry) may have missed. |
| 19 | %% |
| 20 | %% I hope that someone finds this package useful. However, if it goes |
| 21 | %% wrong, that's your problem. I may try and fix it, although the author |
| 22 | %% does not guarantee that this is the case. |
| 23 | %% |
| 24 | %% This pre-release version may be distributed under the terms of the GNU |
| 25 | %% General Public Licence, as published by the Free Software Foundation; |
| 26 | %% either version 2 of the Licence, or (at your option) any later version. |
| 27 | %% However, since this is not finished, and I'd like others to benefit |
| 28 | %% from the finished version, the author BEGS and PLEADS you not to spread |
| 29 | %% this pre-release too much. |
| 30 | %% |
| 31 | % \end{meta-comment} |
| 32 | % |
| 33 | % \begin{meta-comment} <Package preambles> |
| 34 | %<+package>\NeedsTeXFormat{LaTeX2e} |
| 35 | %<+package>\ProvidesPackage{poetry} |
| 36 | %<+package> [1996/05/28 1.00 Poetry typesetting] |
| 37 | % \end{meta-comment} |
| 38 | % |
| 39 | % ^^A \CheckSum{579} |
| 40 | %% \CharacterTable |
| 41 | %% {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 |
| 42 | %% 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 |
| 43 | %% Digits \0\1\2\3\4\5\6\7\8\9 |
| 44 | %% Exclamation \! Double quote \" Hash (number) \# |
| 45 | %% Dollar \$ Percent \% Ampersand \& |
| 46 | %% Acute accent \' Left paren \( Right paren \) |
| 47 | %% Asterisk \* Plus \+ Comma \, |
| 48 | %% Minus \- Point \. Solidus \/ |
| 49 | %% Colon \: Semicolon \; Less than \< |
| 50 | %% Equals \= Greater than \> Question mark \? |
| 51 | %% Commercial at \@ Left bracket \[ Backslash \\ |
| 52 | %% Right bracket \] Circumflex \^ Underscore \_ |
| 53 | %% Grave accent \` Left brace \{ Vertical bar \| |
| 54 | %% Right brace \} Tilde \~} |
| 55 | %% |
| 56 | % |
| 57 | % \begin{meta-comment} |
| 58 | % |
| 59 | %<*driver> |
| 60 | \input{mdwtools} |
| 61 | \describespackage{poetry} |
| 62 | \def\todo#1{% |
| 63 | \par\bigskip\noindent% |
| 64 | \fbox{\dimen0\hsize\advance\dimen0-2\fboxsep% |
| 65 | \parbox{\dimen0}% |
| 66 | {\vskip5pt\centerline{\bfseries TO DO}\vskip 12pt#1}}% |
| 67 | \par\bigskip}% |
| 68 | \mdwdoc |
| 69 | %</driver> |
| 70 | % |
| 71 | % \end{meta-comment} |
| 72 | % |
| 73 | % \section{User guide} |
| 74 | % |
| 75 | % The \package{poem} package is designed to provide appropriate typesetting |
| 76 | % for all manner of `sensible' poems, by which I mean not to exclude the |
| 77 | % works of such great poets as Spike Milligan, but more those who lay out |
| 78 | % their words to form pretty patterns: such works must be dealt with on |
| 79 | % an individual basis, I'm afraid. |
| 80 | % |
| 81 | % An overview of the features provided wouldn't go amiss, I think. |
| 82 | % \begin{itemize} |
| 83 | % |
| 84 | % \item Poems are normally centred on the page based on the length of |
| 85 | % the longest line. This package handles this requirement, but |
| 86 | % allows poems to be left or right aligned if desired. |
| 87 | % |
| 88 | % \item Lines of poems are numbered, and may be labelled and referenced |
| 89 | % using the normal |\label| and |\ref| commands of \LaTeX. Numbers |
| 90 | % are by default printed every 5 lines, on the right hand side, but |
| 91 | % this is fully configurable, as is the style of the numbers. |
| 92 | % |
| 93 | % \item Stanzas can be numbered, titled, either, neither or both. Stanza |
| 94 | % numbers can be labelled and referenced. |
| 95 | % |
| 96 | % \end{itemize} |
| 97 | % |
| 98 | % |
| 99 | % \subsection{Typesetting simple poems} |
| 100 | % |
| 101 | % \DescribeEnv{poem} |
| 102 | % You can typeset a poem using the \env{poem} environment. The lines of |
| 103 | % the poem are separated by |\\| commands as usual. Use the |\stanza*| |
| 104 | % command to start new stanzas. Something like this would do the job: |
| 105 | % |
| 106 | % \todo{There should be a demo here} |
| 107 | % |
| 108 | % Lines of a poem will be broken if they get too long. However, a |
| 109 | % `logical' line of a poem will never be broken between pages.\footnote{ |
| 110 | % This is an artifact of the way I've implemented the poems. I don't |
| 111 | % think it's a terribly nasty restriction.} |
| 112 | % Continued lines are indented from the left margin by a fair distance, |
| 113 | % so that they don't get confused with the starts of new lines. |
| 114 | % |
| 115 | % \DescribeMacro{\poemline} |
| 116 | % You've probably noticed that the poem lines are numbered down the right |
| 117 | % hand side. This happens automatically, although you can turn it off if |
| 118 | % it's inappropriate. All the line numbers are generated by the command |
| 119 | % |\poemline|, which you can define however you like. Saying |
| 120 | % \begin{listing} |
| 121 | %\renewcommand{\poemline}{} |
| 122 | % \end{listing} |
| 123 | % will cause nothing to be printed for the line numbers, turning them off. |
| 124 | % |
| 125 | % \todo{A command to disable numbering?} |
| 126 | % |
| 127 | % \DescribeMacro{\title} |
| 128 | % You can use the |\title| command to typeset a title for your poem. The |
| 129 | % title is inserted right there and then, so watch out. It's conventional |
| 130 | % to put the title at the top of the poem, although this is art we're talking |
| 131 | % about, so who knows? Just say \syntax{"\title{"<title>"}"}. |
| 132 | % |
| 133 | % \DescribeMacro{\author} |
| 134 | % Similarly, the author of a poem can be credited with the |\author| command. |
| 135 | % Just put the author's name in the argument. Authors usually go at the |
| 136 | % bottom of poems. |
| 137 | % |
| 138 | % \DescribeMacro{\poemtitle} \DescribeMacro{\poemauthor} |
| 139 | % The |\title| and |\author| commands are implemented internally by the |
| 140 | % commands |\poemtitle| and |\poemauthor|, which you can redefine if you |
| 141 | % like. You should probably have a look at the default definitions before |
| 142 | % you do this: they use some little features which haven't been described |
| 143 | % yet. Don't be intimidated, though: I'll get to them later! |
| 144 | % |
| 145 | % |
| 146 | % \subsection{Playing with stanzas} |
| 147 | % |
| 148 | % \DescribeMacro{\stanza} |
| 149 | % The |\stanza| command is actually fairly complicated. It always starts |
| 150 | % a new stanza, leaving a gap if necessary after the previous line. |
| 151 | % Also, the stanza will be numbered, unless you use the |\stanza*| command. |
| 152 | % You can also give the stanza a title by saying |
| 153 | % \syntax{"\\stanza["<title>"]"} (or |\stanza*|\dots\ if you don't want the |
| 154 | % number). The title and number are printed above the new stanza. |
| 155 | % |
| 156 | % \DescribeMacro{\labelstanza} |
| 157 | % The stanza numbers are typeset by the command |\labelstanza| which you |
| 158 | % can define however you like. To disable them entirely, say |
| 159 | % \begin{listing} |
| 160 | %\renewcommand{\labelstanza}{} |
| 161 | % \end{listing} |
| 162 | % |
| 163 | % There are a collection of other style parameters for stanza titles. These |
| 164 | % are described below (if you're not interested in this sort of thing, skip |
| 165 | % to the next section). |
| 166 | % |
| 167 | % \begin{description} \def\makelabel#1{\hskip\labelsep\cmd{#1}\hfil} |
| 168 | % \item [stanza] is a \LaTeX\ counter which contains the current stanza |
| 169 | % number. |
| 170 | % \item [\thestanza] typesets the value of the |stanza| counter in normal |
| 171 | % text. |
| 172 | % \item [\labelstanza] typesets the value of the |stanza| counter specially |
| 173 | % for use as a stanza title. (The default style uses small caps here, |
| 174 | % which is generally inappropriate in running text.) |
| 175 | % \item [\stanzaname] is a command with one argument which typesets a stanza |
| 176 | % title string, as passed to the |\stanza| command (not including the |
| 177 | % number). |
| 178 | % \item [\stanzacombine] is given two arguments: a title (built by |
| 179 | % |\labelstanza|) and a title (formatted by |\stanzaname|). It |
| 180 | % should format and space these two arguments. It \emph{can't} |
| 181 | % change the font of this text -- it's too late for that now. |
| 182 | % This command is only used when both a number and a stanza title |
| 183 | % are given. |
| 184 | % \item [\stanzaspace] is called with no arguments. It should somehow |
| 185 | % separate the previous stanza (if any) from the new one. Look at the |
| 186 | % counter value to find out whether this is the first stanza, if it |
| 187 | % matters (e.g., you're drawing little rows of stars or something). |
| 188 | % \item [\stanzatitle] is given one argument: a `combined' title. It should |
| 189 | % typeset the title as a line in LR mode. Again, it's too late to |
| 190 | % play with fonts now. |
| 191 | % \end{description} |
| 192 | % |
| 193 | % All of the commands described above are given fairly simple definitions |
| 194 | % by default: you should be able to customise these without difficulty. |
| 195 | % |
| 196 | % |
| 197 | % \subsection{Starting new lines} |
| 198 | % |
| 199 | % \DescribeMacro{\\} |
| 200 | % New lines within a stanza are started with the |\\| command. This always |
| 201 | % starts a new line. The |\\*| command (which forbids a following page |
| 202 | % break) and the optional argument (which adds vertical space) are |
| 203 | % fully supported. |
| 204 | % |
| 205 | % \DescribeMacro{\nl} |
| 206 | % However, there's also a command |\nl| which works like |\\| (it has a |
| 207 | % $*$-version and so on) except that it won't start a new line unless |
| 208 | % there's something already on the current one. This is useful in commands |
| 209 | % like |\poemauthor| which want to typeset their text on a new line without |
| 210 | % possibly leaving an ugly looking gap. |
| 211 | % |
| 212 | % For example, the definition of |\poemauthor| is: |
| 213 | % \begin{listing} |
| 214 | %\providecommand{\poemauthor}[1]{% |
| 215 | % \nl*[\smallskipamount]% |
| 216 | % \nonumber% |
| 217 | % \hfill\normalfont\itshape#1% |
| 218 | % \\% |
| 219 | %} |
| 220 | % \end{listing} |
| 221 | % The important part to us is that |\nl*[\smallskipamount]| at the |
| 222 | % beginning. This starts a new line, making sure that there's no page |
| 223 | % break between it and the previous line, and adds a little extra space |
| 224 | % before the author's name. The |\nonumber| command just prevents this line |
| 225 | % from being numbered, since it's not actually part of the poem itself: |
| 226 | % numbering is dealt with in detail in the next section. |
| 227 | % |
| 228 | % |
| 229 | % \subsection{Line numbering} |
| 230 | % |
| 231 | % \DescribeMacro{\poemline} |
| 232 | % I skimmed over line numbering earlier, because it's a bit complex. I'll |
| 233 | % start with the default definition of the |\poemline| command, which will |
| 234 | % give me something specific to talk about. The command is used to generate |
| 235 | % the line number for the line which has \emph{just finished}. |
| 236 | % |
| 237 | % \begin{listing} |
| 238 | %\providecommand{\poemline}{% |
| 239 | % \ifmultipleof{5}{\value{poemline}}% |
| 240 | % {\poemlineposition[r]{\scriptsize\thepoemline}}% |
| 241 | % {}% |
| 242 | % \refstepcounter{poemline}% |
| 243 | %} |
| 244 | % \end{listing} |
| 245 | % |
| 246 | % \DescribeMacro{\ifmultipleof} |
| 247 | % The |\ifmultipleof{5}{\value{poemline}}|\dots\ construction restricts the |
| 248 | % printed numbers to every fifth line (|\value{poemline}| is the value of |
| 249 | % the |poemline| counter). Saying |
| 250 | % \syntax{"\\ifmultipleof{"$n$"}{"$x$"}{"<true>"}{"<false>"}"} will do |
| 251 | % \<true> if~$x$ is a multiple of~$n$; otherwise it does \<false>. |
| 252 | % |
| 253 | % \DescribeMacro{\poemlineposition} |
| 254 | % The |\poemlineposition| command positions its text to the right or |
| 255 | % left of the poem, according to whether its optional argument is \lit{l} |
| 256 | % or \lit{r}. |
| 257 | % |
| 258 | % So, the code up there just prints the poem line in small numbers on the |
| 259 | % right hand side of every fifth line of the poem. (Phew!) It then steps |
| 260 | % the counter so it'll be all right for cross-references in the next line |
| 261 | % down. Got that? |
| 262 | % |
| 263 | % \DescribeMacro{\nonumber} |
| 264 | % Something a little simpler now: saying |\nonumber| in a line of poetry will |
| 265 | % suppress the line number on that line. The counter won't be stepped, and |
| 266 | % no number is printed. This is mainly useful in titles and other |
| 267 | % adornments in poems. |
| 268 | % |
| 269 | % |
| 270 | % \subsection{Other little extras} |
| 271 | % |
| 272 | % \DescribeEnv{xpoem} |
| 273 | % The \env{poem} environment doesn't actually do a lot by itself. If you |
| 274 | % look at its definition, you'll see that it just starts a standard \LaTeX\ |
| 275 | % \env{verse} environment and then calls the \env{xpoem} environment to |
| 276 | % do the actual work. The idea is that you can then redefine \env{poem} |
| 277 | % to do whatever setting up you want and then use \env{xpoem} to do |
| 278 | % its typesetting magic. For example, the definitions |
| 279 | % \begin{listing} |
| 280 | %\newcommand{\poemend}{} |
| 281 | %\renewenvironment{poem}[2]{% |
| 282 | % \begin{verse}% |
| 283 | % \renewcommand{\poemend}{\author{#2}}% |
| 284 | % \begin{xpoem}% |
| 285 | % \title{#1}% |
| 286 | %}{% |
| 287 | % \poemend% |
| 288 | % \end{xpoem}% |
| 289 | % \end{verse}% |
| 290 | %} |
| 291 | % \end{listing} |
| 292 | % modifies the environment so that it takes two arguments, the title and |
| 293 | % the author, and sets them at the beginning and end of the poem |
| 294 | % respectively. |
| 295 | % |
| 296 | % \TeX\ hackers who know about such things could make a \env{poem} |
| 297 | % environment which `obeys' line breaks in the input file by making active |
| 298 | % newlines do an |\nl| command. The possibilities are endless. |
| 299 | % |
| 300 | % \DescribeMacro{\splitline} |
| 301 | % The |\splitline| command should be used at the start of a new line (it |
| 302 | % starts a new line all by itself otherwise). It shunts all the text of |
| 303 | % the line to the right so that it starts where the previous line finished. |
| 304 | % |
| 305 | % \todo{Come up with an example for this} |
| 306 | % |
| 307 | % |
| 308 | % \implementation |
| 309 | % |
| 310 | % \section{Implementation} |
| 311 | % |
| 312 | % \subsection{Various allocations} |
| 313 | % |
| 314 | % I need a shocking number of allocations for this package to work. I'll |
| 315 | % start with the counters, because they're probably the most reasonable. |
| 316 | % |
| 317 | % |poem@count| keeps track of which poem this is, so I can look up the |
| 318 | % width in my magic list (I'll describe width handling later in detail). |
| 319 | % |poemline| is a user-level counter which keeps track of the current line |
| 320 | % number. |stanza| keeps track of the current stanza number. |
| 321 | % |
| 322 | % The |\poemchunksize| counter (which is also faked as a \LaTeX\ counter) |
| 323 | % tells me how big a chunk should be. The final counter, |\poem@linesleft| |
| 324 | % tells me how many more lines I can do in this chunk. |
| 325 | % |
| 326 | % All the counters are assigned globally, or at least they should be. |
| 327 | % |
| 328 | % \begin{macrocode} |
| 329 | \newcounter{poem@count} |
| 330 | \newcounter{poemline} |
| 331 | \newcount\poemchunksize |
| 332 | \let\c@poemchunksize\poemchunksize |
| 333 | \newcount\poem@linesleft |
| 334 | \poemchunksize=30 |
| 335 | % \end{macrocode} |
| 336 | % |
| 337 | % Now for some length registers. |\poem@width| contains the width of the |
| 338 | % poem as read from the |.aux| file; |\poem@thiswidth| contains the width |
| 339 | % of the longest line read so far. Both of these are updated as I go through |
| 340 | % the poem. The final value of |\poem@thiswidth| is written back to the |
| 341 | % list when all's finished. |
| 342 | % |
| 343 | % |\poem@lastwidth| contains the width of the last line -- it's used in |
| 344 | % handling |\splitline|s. |\poem@prevdepth| is used to fiddle |\prevdepth| |
| 345 | % when handling long lines. |
| 346 | % |
| 347 | % All of these length parameters should be modified globally at all times. |
| 348 | % |
| 349 | % \begin{macrocode} |
| 350 | \newdimen\poem@width |
| 351 | \newdimen\poem@thiswidth |
| 352 | \newdimen\poem@lastwidth |
| 353 | \newdimen\poem@prevdepth |
| 354 | % \end{macrocode} |
| 355 | % |
| 356 | % The switch |\ifpoem@long| is used to decide whether we need to save the |
| 357 | % poem width in the aux file. |
| 358 | % |
| 359 | % \begin{macrocode} |
| 360 | \newif\ifpoem@long |
| 361 | % \end{macrocode} |
| 362 | % |
| 363 | % Lastly, a skip register. This is the glue on the left hand side of a |
| 364 | % poem. It should be |\@centering| to center the poem horizontally, or |
| 365 | % something rigid and nonzero to left-align. |
| 366 | % |
| 367 | % \begin{macrocode} |
| 368 | \newskip\poemleftskip |
| 369 | \poemleftskip\@centering |
| 370 | % \end{macrocode} |
| 371 | % |
| 372 | % |
| 373 | % \subsection{Handling poem widths} |
| 374 | % |
| 375 | % Poems are horizontally centred, based on the width of their longest line. |
| 376 | % This can be done without too many problems using an |\halign|. However, |
| 377 | % this would require \TeX\ to read in the whole poem before being able to lay |
| 378 | % out the first line; this is clearly impractical for something like |
| 379 | % \emph{The Rime of the Ancient Mariner}. |
| 380 | % |
| 381 | % The solution is fairly similar to that used by the \package{longtable} |
| 382 | % package. I'll divide a poem up into chunks, centring each chunk |
| 383 | % horizontally. I'll also keep track of the longest line so far, and make |
| 384 | % sure that it affects each chunk, so as to prevent the chunks looking odd. |
| 385 | % When all's finished, I'll write a list containing the widths of all the |
| 386 | % poems to the |.aux| file so that next time everything will look nice. |
| 387 | % |
| 388 | % The list is held in just one macro, which contains entries of the form |
| 389 | % \syntax{"["<poem-number>"]{"<width>"}"}. I build the new updated |
| 390 | % list in another macro as I go -- this version will be written to the |
| 391 | % |.aux| file at the very end, to ensure that inserted or removed poems |
| 392 | % don't mess anything up permanently. It also avoids problems to do with |
| 393 | % poem widths decreasing, which gives \package{longtable} a bit of a |
| 394 | % headache. |
| 395 | % |
| 396 | % These two macros are always assigned globally. |
| 397 | % |
| 398 | % \begin{macrocode} |
| 399 | \def\poem@widths{} |
| 400 | \def\poem@savedwidths{} |
| 401 | % \end{macrocode} |
| 402 | % |
| 403 | % \begin{macro}{\poem@getwidth} |
| 404 | % |
| 405 | % The width of the current poem can be read using this macro. It assigns |
| 406 | % the width to the |\poem@width| register; it gets the value 0\,pt if no |
| 407 | % value for this poem actually exists. |
| 408 | % |
| 409 | % \begin{macrocode} |
| 410 | \def\poem@getwidth#1{% |
| 411 | \def\@tempa##1[#1]##2##3\@@{##2}% |
| 412 | \global\poem@width\expandafter\@tempa\poem@savedwidths[#1]\z@\@@% |
| 413 | \relax% |
| 414 | } |
| 415 | % \end{macrocode} |
| 416 | % |
| 417 | % \end{macro} |
| 418 | % |
| 419 | % \begin{macro}{\poem@setwidth} |
| 420 | % |
| 421 | % I can also write the width of the current poem using this macro. It |
| 422 | % updates the new improved list with the value of |\poem@thiswidth|. |
| 423 | % |
| 424 | % \begin{macrocode} |
| 425 | \def\poem@setwidth#1{% |
| 426 | \def\@tempb##1[#1]\z@{##1}% |
| 427 | \def\@tempa##1[#1]##2##3\@@{% |
| 428 | \xdef\poem@widths{% |
| 429 | ##1% |
| 430 | [#1]{\the\poem@thiswidth}% |
| 431 | \ifdim##2=\z@\else\expandafter\@tempb\fi##3% |
| 432 | }% |
| 433 | }% |
| 434 | \expandafter\@tempa\poem@widths[#1]\z@\@@% |
| 435 | } |
| 436 | % \end{macrocode} |
| 437 | % |
| 438 | % \end{macro} |
| 439 | % |
| 440 | % At the very end of the document, I want to write the poem widths to the |
| 441 | % |.aux| file. The following code will do the job nicely. |
| 442 | % |
| 443 | % \begin{macrocode} |
| 444 | \AtEndDocument{% |
| 445 | \if@filesw% |
| 446 | \immediate\write\@auxout% |
| 447 | {\gdef\noexpand\poem@savedwidths{\poem@widths}}% |
| 448 | \fi% |
| 449 | } |
| 450 | % \end{macrocode} |
| 451 | % |
| 452 | % |
| 453 | % \subsection{Some little details} |
| 454 | % |
| 455 | % \begin{macro}{\@maybe@unskip} |
| 456 | % |
| 457 | % This macro solves a little problem. In an alignment (and in other places) |
| 458 | % it's desirable to suppress trailing space. The usual method, to say |
| 459 | % |\unskip|, is a little hamfisted, because it removes perfectly reasonable |
| 460 | % aligning spaces like |\hfil|s. While as a package writer I can deal with |
| 461 | % this sort of thing by saying |\kern\z@| in appropriate places, it can |
| 462 | % annoy users who are trying to use |\hfill| to override alignment in funny |
| 463 | % places. |
| 464 | % |
| 465 | % My current solution seems to be acceptable. I'll remove the natural width |
| 466 | % of the last glue item, so that it can still stretch and shrink if |
| 467 | % necessary. The implementation makes use of the fact that multiplying |
| 468 | % a \<skip> by a \<number> kills off the stretch. |
| 469 | % |
| 470 | % \begin{macrocode} |
| 471 | \def\@maybe@unskip{\hskip-\@ne\lastskip\relax} |
| 472 | % \end{macrocode} |
| 473 | % |
| 474 | % \end{macro} |
| 475 | % |
| 476 | % |
| 477 | % \subsection{Line numbering} |
| 478 | % |
| 479 | % Poem lines are numbered in a fairly sensible and normal way. However, it's |
| 480 | % not normal to number every single line. The macro |\poemline| below will |
| 481 | % decide whether and how to number a line. |
| 482 | % |
| 483 | % \begin{macro}{\ifmultipleof} |
| 484 | % |
| 485 | % This macro is called as |
| 486 | % \syntax{"\\ifmultipleof{"$n$"}{"$x$"}{"<true>"}{"<false>"}"}. If the |
| 487 | % number~$x$ is a multiple of~$n$, then the whole lot expands to \<true>; |
| 488 | % otherwise it expands to \<false>. The test here relies on \TeX\ doing |
| 489 | % integer division (which it does). |
| 490 | % |
| 491 | % \begin{macrocode} |
| 492 | \def\ifmultipleof#1#2{% |
| 493 | \count@#2% |
| 494 | \divide\count@#1% |
| 495 | \multiply\count@#1% |
| 496 | \relax% |
| 497 | \ifnum#2=\count@% |
| 498 | \expandafter\@firstoftwo% |
| 499 | \else% |
| 500 | \expandafter\@secondoftwo% |
| 501 | \fi% |
| 502 | } |
| 503 | % \end{macrocode} |
| 504 | % |
| 505 | % \end{macro} |
| 506 | % |
| 507 | % \begin{macro}{\poemlineposition} |
| 508 | % |
| 509 | % This macro typesets its argument relative to the poem in some neat way. |
| 510 | % It's called as \syntax{"\\poemlineposition["<posn>"]{"<text>"}"}. The |
| 511 | % \<posn> may be \lit{l} or \lit{r}, where `l' and `r' mean left and right |
| 512 | % respectively. |
| 513 | % |
| 514 | % This command only produces at all sensible results when typesetting poem |
| 515 | % line numbers. |
| 516 | % |
| 517 | % \begin{macrocode} |
| 518 | \def\poemlineposition{\@ifnextchar[\poem@lp@i{\poem@lp@i[l]}} |
| 519 | % \end{macrocode} |
| 520 | % |
| 521 | % Now there's some sorting out to do. If the number is to go on the |
| 522 | % right, then there's no problem: it can just be typeset as it is. |
| 523 | % Positioning on the left isn't too hard either -- I just need to shift the |
| 524 | % number to the left by |\linewidth| plus a bit for niceness. |
| 525 | % |
| 526 | % \begin{macrocode} |
| 527 | \def\poem@lp@i[#1]#2{% |
| 528 | \if#1r% |
| 529 | \hfil\kern8\p@#2% |
| 530 | \else\if#1l% |
| 531 | \llap{#2\kern8\p@\kern\linewidth}% |
| 532 | \fi\fi% |
| 533 | } |
| 534 | % \end{macrocode} |
| 535 | % |
| 536 | % \end{macro} |
| 537 | % |
| 538 | % \begin{macro}{\poemline} |
| 539 | % |
| 540 | % The default definition of |\poemline| will put a line number in script |
| 541 | % size (so as not to appear too obvious) on every fifth line. |
| 542 | % |
| 543 | % \begin{macrocode} |
| 544 | \providecommand{\poemline}{% |
| 545 | \ifmultipleof{5}{\value{poemline}}% |
| 546 | {\poemlineposition[r]{\scriptsize\thepoemline}}% |
| 547 | {}% |
| 548 | \refstepcounter{poemline}% |
| 549 | } |
| 550 | % \end{macrocode} |
| 551 | % |
| 552 | % \end{macro} |
| 553 | % |
| 554 | % |
| 555 | % \subsection{The main environment} |
| 556 | % |
| 557 | % \begin{environment}{xpoem} |
| 558 | % |
| 559 | % The \env{xpoem} environment is where the nastiness really starts. |
| 560 | % Actually, the early bit is simple enough. |
| 561 | % |
| 562 | % This environment has a funny name, so that users and style designers can |
| 563 | % define a usable `poem' environment the way they want. Typically this |
| 564 | % will involve playing with some parameters, maybe setting up some active |
| 565 | % characters in a funny way, and probably adding a list environment to |
| 566 | % provide appropriate indentation on the left and right sides. |
| 567 | % |
| 568 | % \begin{macrocode} |
| 569 | \def\xpoem{% |
| 570 | % \end{macrocode} |
| 571 | % |
| 572 | % The first thing to do is to reset the line number counter. |
| 573 | % |
| 574 | % \begin{macrocode} |
| 575 | \global\c@poemline\z@% |
| 576 | % \end{macrocode} |
| 577 | % |
| 578 | % Now for some hookery -- the internal |\poem@printline| command will do |
| 579 | % the job of deciding whether to print a line number or not on the current |
| 580 | % line. Unless otherwise disabled, this will be equal to |\poemline|. |
| 581 | % |
| 582 | % \begin{macrocode} |
| 583 | \global\let\poem@printline\poemline% |
| 584 | % \end{macrocode} |
| 585 | % |
| 586 | % The |\nonumber| command, which is also used by \env{eqnarray},\footnote{^^A |
| 587 | % Just a plug: check out the improved \env{eqnarray} environment in the |
| 588 | % \package{mathenv} package!} |
| 589 | % suppresses numbering of the current line by changing |\poem@printline|. |
| 590 | % It will be reset by the next line end, so it only applies to a single line. |
| 591 | % |
| 592 | % \begin{macrocode} |
| 593 | \def\nonumber{\global\let\poem@printline\@empty}% |
| 594 | % \end{macrocode} |
| 595 | % |
| 596 | % The |\title| and |\author| commands need redefining. I'll set these |
| 597 | % equal to some user-configurable commands below. |
| 598 | % |
| 599 | % \begin{macrocode} |
| 600 | \let\title\poemtitle% |
| 601 | \let\author\poemauthor% |
| 602 | % \end{macrocode} |
| 603 | % |
| 604 | % Do some nasty things to make lists work properly. |
| 605 | % |
| 606 | % \begin{macrocode} |
| 607 | \global\@inlabelfalse% |
| 608 | \global\@newlistfalse% |
| 609 | % \end{macrocode} |
| 610 | % |
| 611 | % Now it's time to start the alignment. I'll clear the |\everycr| tokens, |
| 612 | % and set up the |\\| command. I'll make |\par| expand to nothing exciting, |
| 613 | % so that blank lines in poems won't mess anything up, and set up the |
| 614 | % `outside' meaning of |\nl|. |
| 615 | % |
| 616 | % \begin{macrocode} |
| 617 | \everycr{}% |
| 618 | \let\\\poem@cr% |
| 619 | \def\nl{\poem@nl}% |
| 620 | \global\let\poem@nl\poem@donl% |
| 621 | \let\par\@empty% |
| 622 | % \end{macrocode} |
| 623 | % |
| 624 | % Now to set the widths of the poem. |\poem@width| is read from the |.aux| |
| 625 | % file from the \emph{last} time the poem was typeset, and is used to set |
| 626 | % the width \emph{this} time, while |\poem@thiswidth| is initially zero, |
| 627 | % and is set up as we go through \emph{this} time, and will be used to |
| 628 | % set the actual poem width \emph{next} time. Is that clear? No? Oh, well. |
| 629 | % |
| 630 | % \begin{macrocode} |
| 631 | \expandafter\poem@getwidth\expandafter{\the\c@poem@count}% |
| 632 | \global\poem@thiswidth\z@% |
| 633 | \global\poem@longfalse |
| 634 | % \end{macrocode} |
| 635 | % |
| 636 | % Now some hacking to position the poem horizontally. I need to inspect the |
| 637 | % current list margins, so as to make it look right. I'll set |\dimen@| to |
| 638 | % be the size of the right hand margin. |
| 639 | % |
| 640 | % \begin{macrocode} |
| 641 | \dimen@\hsize% |
| 642 | \advance\dimen@-\@totalleftmargin% |
| 643 | \advance\dimen@-\linewidth% |
| 644 | % \end{macrocode} |
| 645 | % |
| 646 | % Now for some silly little things before I really get going. Leave some |
| 647 | % vertical space, and step the counter ready for the first line. |
| 648 | % |
| 649 | % \begin{macrocode} |
| 650 | \bigskip% |
| 651 | \stepcounter{poemline}% |
| 652 | \def\@currentlabel{\p@poemline\thepoemline}% |
| 653 | % \end{macrocode} |
| 654 | % |
| 655 | % Other things may want to add their declarations here. I'll provide a hook. |
| 656 | % |
| 657 | % \begin{macrocode} |
| 658 | \poem@hook% |
| 659 | % \end{macrocode} |
| 660 | % |
| 661 | % Now start the first poem chunk and give control to the user. |
| 662 | % |
| 663 | % \begin{macrocode} |
| 664 | \poem@startchunk% |
| 665 | } |
| 666 | % \end{macrocode} |
| 667 | % |
| 668 | % That's the start of the environment done; what happens at the end? Well, |
| 669 | % some fairly simple things, actually. |
| 670 | % |
| 671 | % \begin{macrocode} |
| 672 | \def\endxpoem{% |
| 673 | % \end{macrocode} |
| 674 | % |
| 675 | % First of all, I forcibly truncate this chunk of poem. |
| 676 | % |
| 677 | % \begin{macrocode} |
| 678 | \nl% |
| 679 | \poem@endchunk% |
| 680 | % \end{macrocode} |
| 681 | % |
| 682 | % Now, if the poem is longer than the chunk size, I'll add it to the new |
| 683 | % width list. If it's shorter than the chunk size, there's no need to do |
| 684 | % this, since \TeX\ will always work out the correct width `in time'. |
| 685 | % |
| 686 | % \begin{macrocode} |
| 687 | \ifnum\c@poemline>\poemchunksize\poem@longtrue\fi% |
| 688 | \ifpoem@long% |
| 689 | \expandafter\poem@setwidth\expandafter{\the\c@poem@count}% |
| 690 | \fi% |
| 691 | % \end{macrocode} |
| 692 | % |
| 693 | % Now I'll step the poem counter, leave a little gap, and end the |
| 694 | % environment. |
| 695 | % |
| 696 | % \begin{macrocode} |
| 697 | \global\advance\c@poem@count\@ne% |
| 698 | \bigskip% |
| 699 | } |
| 700 | % \end{macrocode} |
| 701 | % |
| 702 | % \end{environment} |
| 703 | % |
| 704 | % \begin{macro}{\poem@hook} |
| 705 | % |
| 706 | % The hook used above in |\poem| starts off empty. Macro packages can add |
| 707 | % to it later. |
| 708 | % |
| 709 | % \begin{macrocode} |
| 710 | \def\poem@hook{} |
| 711 | % \end{macrocode} |
| 712 | % |
| 713 | % \end{macro} |
| 714 | % |
| 715 | % \begin{macro}{\poem@addtohook} |
| 716 | % |
| 717 | % Packages add to that hook by saying |
| 718 | % \syntax{"\\poem@addtohook{"<declarations>"}"}. This is truly trivial. |
| 719 | % |
| 720 | % \begin{macrocode} |
| 721 | \def\poem@addtohook#1{% |
| 722 | \expandafter\def\expandafter\poem@hook\expandafter{\poem@hook#1}% |
| 723 | } |
| 724 | % \end{macrocode} |
| 725 | % |
| 726 | % \end{macro} |
| 727 | % |
| 728 | % I'll take a break from the deep hacking for a while, and implement some |
| 729 | % style things. These commands should be redefined to alter the style of |
| 730 | % the poems. (I've tried hard to make them as simple as possible.) |
| 731 | % |
| 732 | % \begin{macro}{\poemtitle} |
| 733 | % |
| 734 | % Poem titles are large, bold, and centred. The |\nl| command starts a new |
| 735 | % row if necessary. I want to avoid a page break after the title, for |
| 736 | % obvious reasons. |
| 737 | % |
| 738 | % \begin{macrocode} |
| 739 | \providecommand{\poemtitle}[1]{% |
| 740 | \nl% |
| 741 | \nonumber% |
| 742 | \hfill\normalfont\large\bfseries#1\hfill% |
| 743 | \\*[\bigskipamount]% |
| 744 | } |
| 745 | % \end{macrocode} |
| 746 | % |
| 747 | % \end{macro} |
| 748 | % |
| 749 | % \begin{macro}{\poemauthor} |
| 750 | % |
| 751 | % Authors are typeset in italics, right aligned. |
| 752 | % |
| 753 | % \begin{macrocode} |
| 754 | \providecommand{\poemauthor}[1]{% |
| 755 | \nl*[\smallskipamount]% |
| 756 | \nonumber% |
| 757 | \hfill\normalfont\itshape#1% |
| 758 | \\% |
| 759 | } |
| 760 | % \end{macrocode} |
| 761 | % |
| 762 | % \end{macro} |
| 763 | % |
| 764 | % |
| 765 | % \subsection{Poem chunk handling} |
| 766 | % |
| 767 | % Poems are divided into chunks to save \TeX's memory. Chunks are started |
| 768 | % like this: |
| 769 | % |
| 770 | % \begin{macro}{\poem@startchunk} |
| 771 | % |
| 772 | % \begin{macrocode} |
| 773 | \def\poem@startchunk{% |
| 774 | % \end{macrocode} |
| 775 | % |
| 776 | % Reset the `lines left' counter. When this hits zero, I end the chunk and |
| 777 | % start another one. |
| 778 | % |
| 779 | % \begin{macrocode} |
| 780 | \global\poem@linesleft\poemchunksize% |
| 781 | % \end{macrocode} |
| 782 | % |
| 783 | % Now for the alignment itself. The poem is centred by tabskip glue around |
| 784 | % its first column. There are an infinite number of zero-width columns off |
| 785 | % to the right, in which the line numbers are typeset (this avoids problems |
| 786 | % if users accidentally tab over to the next column). |
| 787 | % |
| 788 | % The `main' column is a bit odd. It reads the text into a box, which is |
| 789 | % global to preserve save stack space, and then calls a macro |\poem@doline| |
| 790 | % to typeset the text in the box correctly. |
| 791 | % |
| 792 | % \begin{macrocode} |
| 793 | \skip@\@totalleftmargin% |
| 794 | \advance\skip@\poemleftskip% |
| 795 | \tabskip\skip@% |
| 796 | \halign to\hsize\bgroup% |
| 797 | \global\let\poem@nl\poem@cr% |
| 798 | \global\setbox\@ne\hbox{{\ignorespaces##\@maybe@unskip}}\poem@doline% |
| 799 | \tabskip\@centering&&% |
| 800 | \poem@rightcolumn\hbox{{##}}\tabskip\dimen@\cr% |
| 801 | } |
| 802 | % \end{macrocode} |
| 803 | % |
| 804 | % \end{macro} |
| 805 | % |
| 806 | % \begin{macro}{\poem@endchunk} |
| 807 | % |
| 808 | % This is really easy. I end the line, in case it hasn't been ended already |
| 809 | % (although it should have been), and end the alignment. |
| 810 | % |
| 811 | % \begin{macrocode} |
| 812 | \def\poem@endchunk{% |
| 813 | \crcr% |
| 814 | \noalign{\global\dimen@i\prevdepth\nointerlineskip}% |
| 815 | \omit\hb@xt@\poem@width{}\cr% |
| 816 | \egroup% |
| 817 | \prevdepth\dimen@i% |
| 818 | } |
| 819 | % \end{macrocode} |
| 820 | % |
| 821 | % \end{macro} |
| 822 | % |
| 823 | % |
| 824 | % \subsection{Typesetting poem lines} |
| 825 | % |
| 826 | % \begin{macro}{\poem@doline} |
| 827 | % |
| 828 | % This is where most of the real mess lies. Given a line of doggerel in |
| 829 | % box~1, I must typeset it beautifully. |
| 830 | % |
| 831 | % \begin{macrocode} |
| 832 | \def\poem@doline{% |
| 833 | % \end{macrocode} |
| 834 | % |
| 835 | % In order to know whether I need to split the line, I must know how wide |
| 836 | % the line number is. (Judging from the books I've seen, lines are allowed |
| 837 | % to encroach on the space allocated to line numbers, as long as there isn't |
| 838 | % a number on this line. Maybe as a future extension, I could decide whether |
| 839 | % it might be better to suppress this line, and maybe force a number for |
| 840 | % the next one since it won't fit here.) |
| 841 | % |
| 842 | % Anyway, I'll do this the easy way. I'll work out the width of the line |
| 843 | % number, and subtract it from the basic line width. |
| 844 | % |
| 845 | % \begin{macrocode} |
| 846 | \dimen@\linewidth% |
| 847 | \global\setbox\@labels\hbox{\poem@printline}% |
| 848 | \advance\dimen@-\wd\@labels% |
| 849 | % \end{macrocode} |
| 850 | % |
| 851 | % If the width of the doggerel is wider than |\dimen@|, I must split the |
| 852 | % text over more than one line, or at least I must try to. (\TeX\ may |
| 853 | % be able to squeeze the text onto one line by shrinking the glue, so I've |
| 854 | % got to watch out for this possibility.) |
| 855 | % |
| 856 | % \begin{macrocode} |
| 857 | \ifdim\wd\@ne>\dimen@% |
| 858 | % \end{macrocode} |
| 859 | % |
| 860 | % I'll now put the text in a vbox, so I can play with it. The parshape |
| 861 | % is set up so that the first line misses the line number (if there is |
| 862 | % one), while subsequent lines are indented, but take up the full available |
| 863 | % width of the page. The text is not indented (just to make sure). |
| 864 | % |
| 865 | % The messing with |\leftskip| and the initial kern provides the indentation, |
| 866 | % and saves a little arithmetic. There is a more plausible historical reason |
| 867 | % for it too. |
| 868 | % |
| 869 | % \begin{macrocode} |
| 870 | \global\setbox\@ne\vtop{% |
| 871 | \parshape\tw@ \z@\dimen@ \z@\linewidth% |
| 872 | \leftskip3em% |
| 873 | \noindent% |
| 874 | \kern-3em% |
| 875 | \unhbox\@ne% |
| 876 | \@@par% |
| 877 | }% |
| 878 | % \end{macrocode} |
| 879 | % |
| 880 | % Since table cells are set in LR mode, the baselineskip glue will be set |
| 881 | % all wrong underneath this line. I also need to set |\poem@lastwidth| |
| 882 | % correctly. I'll copy the box to another box, and pick off the bottom line |
| 883 | % so I can peek inside. |
| 884 | % |
| 885 | % I'll set |\poem@prevdepth| from the depth of the box (this will be set |
| 886 | % properly at the end of the line). I'll also rip that box apart, remove |
| 887 | % the |\parfillskip| glue, and rebox it in an attempt to calculate |
| 888 | % |\poem@lastwidth|. This isn't perfect, since the line might actually be |
| 889 | % shrinking instead of stretching. This is unlikely, though. |
| 890 | % |
| 891 | % \begin{macrocode} |
| 892 | \global\setbox\thr@@\vbox{% |
| 893 | \unvcopy\@ne% |
| 894 | \global\setbox\thr@@\lastbox% |
| 895 | \global\poem@prevdepth\dp\thr@@% |
| 896 | \global\setbox\thr@@\hbox{\unhbox\thr@@\unskip}% |
| 897 | \global\poem@lastwidth\wd\thr@@% |
| 898 | }% |
| 899 | % \end{macrocode} |
| 900 | % |
| 901 | % Now that's done, I can output the box. I'll clear box~3, which I |
| 902 | % vandalised above. I also know that the line was too long, so I can |
| 903 | % set the poem widths to |\linewidth| with impunity. |
| 904 | % |
| 905 | % \begin{macrocode} |
| 906 | \box\@ne% |
| 907 | \global\setbox\thr@@\box\voidb@x% |
| 908 | \global\poem@width\linewidth% |
| 909 | \global\poem@thiswidth\linewidth% |
| 910 | \else% |
| 911 | % \end{macrocode} |
| 912 | % |
| 913 | % If it fits, I can update the widths if necessary, set |\poem@lastwidth|, |
| 914 | % and spew out the text. Finally, I'll set |\poem@prevdepth| to a sentinel |
| 915 | % value meaning `don't change'. |
| 916 | % |
| 917 | % \begin{macrocode} |
| 918 | \ifdim\wd\@ne>\poem@width\global\poem@width\wd\@ne\fi% |
| 919 | \ifdim\wd\@ne>\poem@thiswidth\global\poem@thiswidth\wd\@ne\fi% |
| 920 | \global\poem@lastwidth\wd\@ne% |
| 921 | \unhbox\@ne\hfil% |
| 922 | \global\poem@prevdepth\maxdimen% |
| 923 | \fi% |
| 924 | } |
| 925 | % \end{macrocode} |
| 926 | % |
| 927 | % \end{macro} |
| 928 | % |
| 929 | % |
| 930 | % \subsection{Starting a new line} |
| 931 | % |
| 932 | % There are two different routes to starting new lines. The |\\| command |
| 933 | % always starts a new line. The command |\nl| will work out if |
| 934 | % the current line hasn't been started yet, and behaves appropriately. |
| 935 | % |
| 936 | % \begin{macro}{\poem@cr} |
| 937 | % |
| 938 | % The |\poem@cr| macro implements the |\\| command and the |\nl| |
| 939 | % command once a new line has been started. |
| 940 | % |
| 941 | % First, I need to pick out the optional arguments. All the standard hacking |
| 942 | % for doing newlines in alignments appears here. If you want detailed |
| 943 | % commentary, look somewhere else -- this is humdrum stuff now. |
| 944 | % |
| 945 | % \begin{macrocode} |
| 946 | \def\poem@cr{% |
| 947 | \relax% |
| 948 | \global\let\poem@nl\poem@donl% |
| 949 | \iffalse{\fi\ifnum0=`}\fi% |
| 950 | \@ifstar{\poem@cr@i\@M}{\poem@cr@i\z@}% |
| 951 | } |
| 952 | \def\poem@cr@i#1{\@ifnextchar[{\poem@cr@ii{#1}}{\poem@cr@ii{#1}[\z@]}} |
| 953 | % \end{macrocode} |
| 954 | % |
| 955 | % That's the standard hacking over. Here's the tricky bit. |
| 956 | % |
| 957 | % \begin{macrocode} |
| 958 | \def\poem@cr@ii#1[#2]{% |
| 959 | \ifnum0=`{}\fi% |
| 960 | % \end{macrocode} |
| 961 | % |
| 962 | % First of all, I must clear the command which raises an error in the right |
| 963 | % hand column. Then I'll enter the column and insert the line number (which |
| 964 | % was stored in |\@labels| for safekeeping). |
| 965 | % |
| 966 | % \begin{macrocode} |
| 967 | \global\let\poem@rightcolumn\relax% |
| 968 | &\relax% |
| 969 | \llap{\unhbox\@labels}% |
| 970 | % \end{macrocode} |
| 971 | % |
| 972 | % Now I'll reset the various hooks and things ready for the next like. |
| 973 | % |
| 974 | % \begin{macrocode} |
| 975 | \global\let\poem@printline\poemline% |
| 976 | \global\let\poem@rightcolumn\poem@@rightcolumn% |
| 977 | % \end{macrocode} |
| 978 | % |
| 979 | % Now to decide whether to start a new chunk. I'll decrement the counter, |
| 980 | % and if it reaches zero, I'll end that chunk and start a new one. |
| 981 | % |
| 982 | % \begin{macrocode} |
| 983 | \global\advance\poem@linesleft\m@ne% |
| 984 | \ifnum\poem@linesleft=\z@% |
| 985 | \poem@endchunk% |
| 986 | \expandafter\poem@startchunk% |
| 987 | \else% |
| 988 | \expandafter\cr% |
| 989 | \fi% |
| 990 | % \end{macrocode} |
| 991 | % |
| 992 | % Finally, if I had a split line, I must change the |\prevdepth| setting to |
| 993 | % keep everyone happy. |
| 994 | % |
| 995 | % \begin{macrocode} |
| 996 | \noalign{% |
| 997 | \addpenalty{#1}% |
| 998 | \vskip#2% |
| 999 | \ifdim\poem@prevdepth=\maxdimen\else\prevdepth\poem@prevdepth\fi% |
| 1000 | }% |
| 1001 | } |
| 1002 | % \end{macrocode} |
| 1003 | % |
| 1004 | % \end{macro} |
| 1005 | % |
| 1006 | % \begin{macro}{\poem@donl} |
| 1007 | % |
| 1008 | % The |\poem@nl| macro implements |\nl| during those `in-between' times |
| 1009 | % outside of a line of doggerel. This is actually spectacularly easy. |
| 1010 | % |
| 1011 | % \begin{macrocode} |
| 1012 | \def\poem@donl{% |
| 1013 | \noalign{\ifnum0=`}\fi% |
| 1014 | \@ifstar{\poem@donl@i{\addpenalty\@M}}{\poem@donl@i{}}% |
| 1015 | } |
| 1016 | \def\poem@donl@i#1{% |
| 1017 | \@ifnextchar[{\poem@donl@ii{#1}}{\poem@donl@ii{#1}[\z@]}% |
| 1018 | } |
| 1019 | \def\poem@donl@ii#1[#2]{% |
| 1020 | #1% |
| 1021 | \addvspace{#2}% |
| 1022 | \ifnum0=`{\fi}% |
| 1023 | } |
| 1024 | % \end{macrocode} |
| 1025 | % |
| 1026 | % \end{macro} |
| 1027 | % |
| 1028 | % |
| 1029 | % \subsection{Other things} |
| 1030 | % |
| 1031 | % Well, that's all that I actually need to supply; everything else can be |
| 1032 | % added over the top. |
| 1033 | % |
| 1034 | % \begin{macro}{\splitline} |
| 1035 | % |
| 1036 | % Some books appear to split lines, starting the second where the first |
| 1037 | % ends. This is easy to handle with the |\splitline| command. |
| 1038 | % |
| 1039 | % \begin{macrocode} |
| 1040 | \def\splitline{\nl\nonumber\kern\poem@lastwidth\ } |
| 1041 | % \end{macrocode} |
| 1042 | % |
| 1043 | % \end{macro} |
| 1044 | % |
| 1045 | % \begin{macro}{\stanza} |
| 1046 | % |
| 1047 | % New stanzas are started using the |\stanza| command, oddly enough. There's |
| 1048 | % a problem, though: to number, or not to number? Following the example of |
| 1049 | % \LaTeX's sectioning commands, I'll not number if there's a following $*$. |
| 1050 | % I don't really think that this is the right thing to do, since unnumbered |
| 1051 | % stanzas are much more common than numbered ones. This is actually a real |
| 1052 | % pain. |
| 1053 | % |
| 1054 | % Anyway, if I'm going to handle numbered stanzas, I'll need a counter. |
| 1055 | % |
| 1056 | % \begin{macrocode} |
| 1057 | \newcounter{stanza} |
| 1058 | % \end{macrocode} |
| 1059 | % |
| 1060 | % Whatever happens, I'll start by adding in some vertical space above the |
| 1061 | % stanza. Then I'll see if there's a following $*$. If so, step the counter |
| 1062 | % and typeset the number; otherwise do nothing. However, there's a snaglet |
| 1063 | % here: |\@ifstar| will do assignments and things, and start the next row of |
| 1064 | % the alignment prematurely. I'll do the work in a |\noalign| to avoid |
| 1065 | % problems. (Yuk.) |
| 1066 | % |
| 1067 | % \begin{macrocode} |
| 1068 | \def\stanza{% |
| 1069 | \nl% |
| 1070 | \noalign{\ifnum0=`}\fi% |
| 1071 | \@ifstar{% |
| 1072 | \stanza@i{}% |
| 1073 | }{% |
| 1074 | \stanza@i{\global\advance\c@stanza\@ne\labelstanza}% |
| 1075 | }% |
| 1076 | } |
| 1077 | % \end{macrocode} |
| 1078 | % |
| 1079 | % OK\@. Now I have to see if there's an optional argument. I'm still safely |
| 1080 | % inside that |\noalign|, remember. |
| 1081 | % |
| 1082 | % \begin{macrocode} |
| 1083 | \def\stanza@i#1{\@ifnextchar[{\stanza@ii{#1}}{\stanza@ii{#1}[]}} |
| 1084 | % \end{macrocode} |
| 1085 | % |
| 1086 | % I can now read the argument, and decide what actually needs to be done. |
| 1087 | % |
| 1088 | % \begin{macrocode} |
| 1089 | \def\stanza@ii#1[#2]{% |
| 1090 | % \end{macrocode} |
| 1091 | % |
| 1092 | % I want to be able to allow |\label|s inside the optional argument. |
| 1093 | % However, I also want to be able to see whether the number and/or title |
| 1094 | % is `empty', bearing in mind that the title may contain just a |\label|, |
| 1095 | % which shouldn't alter the spacing; which means really that I ought to put |
| 1096 | % them into boxes and measure them. But this stops |\refstepcounter|'s |
| 1097 | % setting of |\@currentlabel| (in the `number' box) being noticed by the |
| 1098 | % possible |\label| command in the other box. I \emph{could} say something |
| 1099 | % like |
| 1100 | % \begin{listing} |
| 1101 | %\refstepcounter{stanza} |
| 1102 | %\addtocounter{stanza}{-1} |
| 1103 | % \end{listing} |
| 1104 | % which will do what I want, but defining |\@currentlabel| by hand is |
| 1105 | % considerably easier, and more efficient. |
| 1106 | % |
| 1107 | % \begin{macrocode} |
| 1108 | \def\@currentlabel{\p@stanza\thestanza}% |
| 1109 | \sbox\z@{#1}% |
| 1110 | \sbox\tw@{\stanzaname{#2}}% |
| 1111 | % \end{macrocode} |
| 1112 | % |
| 1113 | % There are essentially four possibilities: |
| 1114 | % \begin{itemize} |
| 1115 | % \item There's nothing to typeset at all. This is easy: don't typeset |
| 1116 | % anything. |
| 1117 | % \item There's a number, but no title. |
| 1118 | % \item There's a title, but no number. |
| 1119 | % \item There's both a title \emph{and} a number. |
| 1120 | % \end{itemize} |
| 1121 | % The tricky bit is the last possibility, since I don't know how the two |
| 1122 | % will be separated. Oh, well: I'll just have to use a load of user macros. |
| 1123 | % |
| 1124 | % As a first attempt, I'll put the thing to typeset into box~0. This is |
| 1125 | % fairly simple. If there's a title, then I check if there's a number too: |
| 1126 | % if so, I'll combine them both into box~0; otherwise I can just copy the |
| 1127 | % box over. If there's anything to typeset at this point, it'll be in |
| 1128 | % box~0. However, I'm currently in a |\noalign|, and that introduces a |
| 1129 | % level of grouping. So I'll then move the box into box~1, which is global. |
| 1130 | % |
| 1131 | % \begin{macrocode} |
| 1132 | \ifdim\wd\tw@>\z@% |
| 1133 | \ifdim\wd\z@>\z@% |
| 1134 | \global\setbox\@ne\hbox{\stanzacombine{\unhbox\z@}{\unhbox\tw@}}% |
| 1135 | \else% |
| 1136 | \global\setbox\@ne\box\tw@% |
| 1137 | \fi% |
| 1138 | \else% |
| 1139 | \global\setbox\@ne\hbox{\unhbox\z@\unhbox\tw@}% |
| 1140 | \fi% |
| 1141 | % \end{macrocode} |
| 1142 | % |
| 1143 | % That's all the messy processing done. Now I can just typeset the |
| 1144 | % title. |
| 1145 | % |
| 1146 | % \begin{macrocode} |
| 1147 | \ifnum0=`{\fi}% |
| 1148 | \stanzaspace% |
| 1149 | \ifdim\wd\@ne>\z@% |
| 1150 | \nonumber% |
| 1151 | \stanzatitle{\unhbox\@ne}% |
| 1152 | \else |
| 1153 | \fi% |
| 1154 | % \end{macrocode} |
| 1155 | % |
| 1156 | % That's it! I'm done. |
| 1157 | % |
| 1158 | % \begin{macrocode} |
| 1159 | } |
| 1160 | % \end{macrocode} |
| 1161 | % |
| 1162 | % \end{macro} |
| 1163 | % |
| 1164 | % The |stanza| counter must be reset at the beginning of the poem. |
| 1165 | % |
| 1166 | % \begin{macrocode} |
| 1167 | \poem@addtohook{\global\c@stanza\z@} |
| 1168 | % \end{macrocode} |
| 1169 | % |
| 1170 | % Now for some formatting defaults. This is easy stuff. |
| 1171 | % |
| 1172 | % |
| 1173 | % \begin{macro}{\thestanza} |
| 1174 | % |
| 1175 | % Obviously, this is the default way to typeset a stanza number. |
| 1176 | % |
| 1177 | % \begin{macrocode} |
| 1178 | \renewcommand{\thestanza}{\Roman{stanza}} |
| 1179 | % \end{macrocode} |
| 1180 | % |
| 1181 | % \end{macro} |
| 1182 | % |
| 1183 | % \begin{macro}{\labelstanza} |
| 1184 | % |
| 1185 | % This macro is responsible for giving the stanza number to be typeset in |
| 1186 | % the title line. |
| 1187 | % |
| 1188 | % \begin{macrocode} |
| 1189 | \providecommand{\labelstanza}{\textsc{\roman{stanza}}} |
| 1190 | % \end{macrocode} |
| 1191 | % |
| 1192 | % \end{macro} |
| 1193 | % |
| 1194 | % \begin{macro}{\stanzaname} |
| 1195 | % |
| 1196 | % This is responsible for typesetting the stanza's name. This is easy. |
| 1197 | % |
| 1198 | % \begin{macrocode} |
| 1199 | \providecommand{\stanzaname}[1]{\textsc{#1}} |
| 1200 | % \end{macrocode} |
| 1201 | % |
| 1202 | % \end{macro} |
| 1203 | % |
| 1204 | % \begin{macro}{\stanzacombine} |
| 1205 | % |
| 1206 | % This is how to combine stanza numbers and names. I'll just leave a space. |
| 1207 | % |
| 1208 | % \begin{macrocode} |
| 1209 | \providecommand{\stanzacombine}[2]{#1\quad#2} |
| 1210 | % \end{macrocode} |
| 1211 | % |
| 1212 | % \end{macro} |
| 1213 | % |
| 1214 | % \begin{macro}{\stanzaspace} |
| 1215 | % |
| 1216 | % Separate the previous stanza from a new one. This isn't done in |
| 1217 | % |\stanzatitle| because there may not be a title. |
| 1218 | % |
| 1219 | % \begin{macrocode} |
| 1220 | \providecommand{\stanzaspace}{\nl[\medskipamount]} |
| 1221 | % \end{macrocode} |
| 1222 | % |
| 1223 | % \end{macro} |
| 1224 | % |
| 1225 | % \begin{macro}{\stanzatitle} |
| 1226 | % |
| 1227 | % Finally, this is the typesetting of the stanza title in its entirety. |
| 1228 | % |
| 1229 | % \begin{macrocode} |
| 1230 | \providecommand{\stanzatitle}[1]{% |
| 1231 | \hfill#1\hfill\\% |
| 1232 | } |
| 1233 | % \end{macrocode} |
| 1234 | % |
| 1235 | % \end{macro} |
| 1236 | % |
| 1237 | % |
| 1238 | % \hfill Mark Wooding, \today |
| 1239 | % |
| 1240 | % \Finale |
| 1241 | % |
| 1242 | \endinput |