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2 | =for comment | |
3 | This document is in Pod format. To read this, use a Pod formatter, | |
4 | like "perldoc perlpod". | |
5 | ||
6 | =head1 NAME | |
7 | ||
8 | perlpod - the Plain Old Documentation format | |
9 | ||
10 | =head1 DESCRIPTION | |
11 | ||
12 | Pod is a simple-to-use markup language used for writing documentation | |
13 | for Perl, Perl programs, and Perl modules. | |
14 | ||
15 | Translators are available for converting Pod to various formats | |
16 | like plain text, HTML, man pages, and more. | |
17 | ||
18 | Pod markup consists of three basic kinds of paragraphs: | |
19 | L<ordinary|/"Ordinary Paragraph">, | |
20 | L<verbatim|/"Verbatim Paragraph">, and | |
21 | L<command|/"Command Paragraph">. | |
22 | ||
23 | ||
24 | =head2 Ordinary Paragraph | |
25 | ||
26 | Most paragraphs in your documentation will be ordinary blocks | |
27 | of text, like this one. You can simply type in your text without | |
28 | any markup whatsoever, and with just a blank line before and | |
29 | after. When it gets formatted, it will undergo minimal formatting, | |
30 | like being rewrapped, probably put into a proportionally spaced | |
31 | font, and maybe even justified. | |
32 | ||
33 | You can use formatting codes in ordinary paragraphs, for B<bold>, | |
34 | I<italic>, C<code-style>, L<hyperlinks|perlfaq>, and more. Such | |
35 | codes are explained in the "L<Formatting Codes|/"Formatting Codes">" | |
36 | section, below. | |
37 | ||
38 | ||
39 | =head2 Verbatim Paragraph | |
40 | ||
41 | Verbatim paragraphs are usually used for presenting a codeblock or | |
42 | other text which does not require any special parsing or formatting, | |
43 | and which shouldn't be wrapped. | |
44 | ||
45 | A verbatim paragraph is distinguished by having its first character | |
46 | be a space or a tab. (And commonly, all its lines begin with spaces | |
47 | and/or tabs.) It should be reproduced exactly, with tabs assumed to | |
48 | be on 8-column boundaries. There are no special formatting codes, | |
49 | so you can't italicize or anything like that. A \ means \, and | |
50 | nothing else. | |
51 | ||
52 | ||
53 | =head2 Command Paragraph | |
54 | ||
55 | A command paragraph is used for special treatment of whole chunks | |
56 | of text, usually as headings or parts of lists. | |
57 | ||
58 | All command paragraphs (which are typically only one line long) start | |
59 | with "=", followed by an identifier, followed by arbitrary text that | |
60 | the command can use however it pleases. Currently recognized commands | |
61 | are | |
62 | ||
63 | =head1 Heading Text | |
64 | =head2 Heading Text | |
65 | =head3 Heading Text | |
66 | =head4 Heading Text | |
67 | =over indentlevel | |
68 | =item stuff | |
69 | =back | |
70 | =cut | |
71 | =pod | |
72 | =begin format | |
73 | =end format | |
74 | =for format text... | |
75 | ||
76 | To explain them each in detail: | |
77 | ||
78 | =over | |
79 | ||
80 | =item C<=head1 I<Heading Text>> | |
81 | ||
82 | =item C<=head2 I<Heading Text>> | |
83 | ||
84 | =item C<=head3 I<Heading Text>> | |
85 | ||
86 | =item C<=head4 I<Heading Text>> | |
87 | ||
88 | Head1 through head4 produce headings, head1 being the highest | |
89 | level. The text in the rest of this paragraph is the content of the | |
90 | heading. For example: | |
91 | ||
92 | =head2 Object Attributes | |
93 | ||
94 | The text "Object Attributes" comprises the heading there. (Note that | |
95 | head3 and head4 are recent additions, not supported in older Pod | |
96 | translators.) The text in these heading commands can use | |
97 | formatting codes, as seen here: | |
98 | ||
99 | =head2 Possible Values for C<$/> | |
100 | ||
101 | Such commands are explained in the | |
102 | "L<Formatting Codes|/"Formatting Codes">" section, below. | |
103 | ||
104 | =item C<=over I<indentlevel>> | |
105 | ||
106 | =item C<=item I<stuff...>> | |
107 | ||
108 | =item C<=back> | |
109 | ||
110 | Item, over, and back require a little more explanation: "=over" starts | |
111 | a region specifically for the generation of a list using "=item" | |
112 | commands, or for indenting (groups of) normal paragraphs. At the end | |
113 | of your list, use "=back" to end it. The I<indentlevel> option to | |
114 | "=over" indicates how far over to indent, generally in ems (where | |
115 | one em is the width of an "M" in the document's base font) or roughly | |
116 | comparable units; if there is no I<indentlevel> option, it defaults | |
117 | to four. (And some formatters may just ignore whatever I<indentlevel> | |
118 | you provide.) In the I<stuff> in C<=item I<stuff...>>, you may | |
119 | use formatting codes, as seen here: | |
120 | ||
121 | =item Using C<$|> to Control Buffering | |
122 | ||
123 | Such commands are explained in the | |
124 | "L<Formatting Codes|/"Formatting Codes">" section, below. | |
125 | ||
126 | Note also that there are some basic rules to using "=over" ... | |
127 | "=back" regions: | |
128 | ||
129 | =over | |
130 | ||
131 | =item * | |
132 | ||
133 | Don't use "=item"s outside of an "=over" ... "=back" region. | |
134 | ||
135 | =item * | |
136 | ||
137 | The first thing after the "=over" command should be an "=item", unless | |
138 | there aren't going to be any items at all in this "=over" ... "=back" | |
139 | region. | |
140 | ||
141 | =item * | |
142 | ||
143 | Don't put "=headI<n>" commands inside an "=over" ... "=back" region. | |
144 | ||
145 | =item * | |
146 | ||
147 | And perhaps most importantly, keep the items consistent: either use | |
148 | "=item *" for all of them, to produce bullets; or use "=item 1.", | |
149 | "=item 2.", etc., to produce numbered lists; or use "=item foo", | |
150 | "=item bar", etc. -- namely, things that look nothing like bullets or | |
151 | numbers. | |
152 | ||
153 | If you start with bullets or numbers, stick with them, as | |
154 | formatters use the first "=item" type to decide how to format the | |
155 | list. | |
156 | ||
157 | =back | |
158 | ||
159 | =item C<=cut> | |
160 | ||
161 | To end a Pod block, use a blank line, | |
162 | then a line beginning with "=cut", and a blank | |
163 | line after it. This lets Perl (and the Pod formatter) know that | |
164 | this is where Perl code is resuming. (The blank line before the "=cut" | |
165 | is not technically necessary, but many older Pod processors require it.) | |
166 | ||
167 | =item C<=pod> | |
168 | ||
169 | The "=pod" command by itself doesn't do much of anything, but it | |
170 | signals to Perl (and Pod formatters) that a Pod block starts here. A | |
171 | Pod block starts with I<any> command paragraph, so a "=pod" command is | |
172 | usually used just when you want to start a Pod block with an ordinary | |
173 | paragraph or a verbatim paragraph. For example: | |
174 | ||
175 | =item stuff() | |
176 | ||
177 | This function does stuff. | |
178 | ||
179 | =cut | |
180 | ||
181 | sub stuff { | |
182 | ... | |
183 | } | |
184 | ||
185 | =pod | |
186 | ||
187 | Remember to check its return value, as in: | |
188 | ||
189 | stuff() || die "Couldn't do stuff!"; | |
190 | ||
191 | =cut | |
192 | ||
193 | =item C<=begin I<formatname>> | |
194 | ||
195 | =item C<=end I<formatname>> | |
196 | ||
197 | =item C<=for I<formatname> I<text...>> | |
198 | ||
199 | For, begin, and end will let you have regions of text/code/data that | |
200 | are not generally interpreted as normal Pod text, but are passed | |
201 | directly to particular formatters, or are otherwise special. A | |
202 | formatter that can use that format will use the region, otherwise it | |
203 | will be completely ignored. | |
204 | ||
205 | A command "=begin I<formatname>", some paragraphs, and a | |
206 | command "=end I<formatname>", mean that the text/data inbetween | |
207 | is meant for formatters that understand the special format | |
208 | called I<formatname>. For example, | |
209 | ||
210 | =begin html | |
211 | ||
212 | <hr> <img src="thang.png"> | |
213 | <p> This is a raw HTML paragraph </p> | |
214 | ||
215 | =end html | |
216 | ||
217 | The command "=for I<formatname> I<text...>" | |
218 | specifies that the remainder of just this paragraph (starting | |
219 | right after I<formatname>) is in that special format. | |
220 | ||
221 | =for html <hr> <img src="thang.png"> | |
222 | <p> This is a raw HTML paragraph </p> | |
223 | ||
224 | This means the same thing as the above "=begin html" ... "=end html" | |
225 | region. | |
226 | ||
227 | That is, with "=for", you can have only one paragraph's worth | |
228 | of text (i.e., the text in "=foo targetname text..."), but with | |
229 | "=begin targetname" ... "=end targetname", you can have any amount | |
230 | of stuff inbetween. (Note that there still must be a blank line | |
231 | after the "=begin" command and a blank line before the "=end" | |
232 | command. | |
233 | ||
234 | Here are some examples of how to use these: | |
235 | ||
236 | =begin html | |
237 | ||
238 | <br>Figure 1.<br><IMG SRC="figure1.png"><br> | |
239 | ||
240 | =end html | |
241 | ||
242 | =begin text | |
243 | ||
244 | --------------- | |
245 | | foo | | |
246 | | bar | | |
247 | --------------- | |
248 | ||
249 | ^^^^ Figure 1. ^^^^ | |
250 | ||
251 | =end text | |
252 | ||
253 | Some format names that formatters currently are known to accept | |
254 | include "roff", "man", "latex", "tex", "text", and "html". (Some | |
255 | formatters will treat some of these as synonyms.) | |
256 | ||
257 | A format name of "comment" is common for just making notes (presumably | |
258 | to yourself) that won't appear in any formatted version of the Pod | |
259 | document: | |
260 | ||
261 | =for comment | |
262 | Make sure that all the available options are documented! | |
263 | ||
264 | Some I<formatnames> will require a leading colon (as in | |
265 | C<"=for :formatname">, or | |
266 | C<"=begin :formatname" ... "=end :formatname">), | |
267 | to signal that the text is not raw data, but instead I<is> Pod text | |
268 | (i.e., possibly containing formatting codes) that's just not for | |
269 | normal formatting (e.g., may not be a normal-use paragraph, but might | |
270 | be for formatting as a footnote). | |
271 | ||
272 | =back | |
273 | ||
274 | And don't forget, when using any command, that the command lasts up | |
275 | until the end of its I<paragraph>, not its line. So in the | |
276 | examples below, you can see that every command needs the blank | |
277 | line after it, to end its paragraph. | |
278 | ||
279 | Some examples of lists include: | |
280 | ||
281 | =over | |
282 | ||
283 | =item * | |
284 | ||
285 | First item | |
286 | ||
287 | =item * | |
288 | ||
289 | Second item | |
290 | ||
291 | =back | |
292 | ||
293 | =over | |
294 | ||
295 | =item Foo() | |
296 | ||
297 | Description of Foo function | |
298 | ||
299 | =item Bar() | |
300 | ||
301 | Description of Bar function | |
302 | ||
303 | =back | |
304 | ||
305 | ||
306 | =head2 Formatting Codes | |
307 | ||
308 | In ordinary paragraphs and in some command paragraphs, various | |
309 | formatting codes (a.k.a. "interior sequences") can be used: | |
310 | ||
311 | =for comment | |
312 | "interior sequences" is such an opaque term. | |
313 | Prefer "formatting codes" instead. | |
314 | ||
315 | =over | |
316 | ||
317 | =item C<IE<lt>textE<gt>> -- italic text | |
318 | ||
319 | Used for emphasis ("C<be IE<lt>careful!E<gt>>") and parameters | |
320 | ("C<redo IE<lt>LABELE<gt>>") | |
321 | ||
322 | =item C<BE<lt>textE<gt>> -- bold text | |
323 | ||
324 | Used for switches ("C<perl's BE<lt>-nE<gt> switch>"), programs | |
325 | ("C<some systems provide a BE<lt>chfnE<gt> for that>"), | |
326 | emphasis ("C<be BE<lt>careful!E<gt>>"), and so on | |
327 | ("C<and that feature is known as BE<lt>autovivificationE<gt>>"). | |
328 | ||
329 | =item C<CE<lt>codeE<gt>> -- code text | |
330 | ||
331 | Renders code in a typewriter font, or gives some other indication that | |
332 | this represents program text ("C<CE<lt>gmtime($^T)E<gt>>") or some other | |
333 | form of computerese ("C<CE<lt>drwxr-xr-xE<gt>>"). | |
334 | ||
335 | =item C<LE<lt>nameE<gt>> -- a hyperlink | |
336 | ||
337 | There are various syntaxes, listed below. In the syntaxes given, | |
338 | C<text>, C<name>, and C<section> cannot contain the characters | |
339 | '/' and '|'; and any '<' or '>' should be matched. | |
340 | ||
341 | =over | |
342 | ||
343 | =item * | |
344 | ||
345 | C<LE<lt>nameE<gt>> | |
346 | ||
347 | Link to a Perl manual page (e.g., C<LE<lt>Net::PingE<gt>>). Note | |
348 | that C<name> should not contain spaces. This syntax | |
349 | is also occasionally used for references to UNIX man pages, as in | |
350 | C<LE<lt>crontab(5)E<gt>>. | |
351 | ||
352 | =item * | |
353 | ||
354 | C<LE<lt>name/"sec"E<gt>> or C<LE<lt>name/secE<gt>> | |
355 | ||
356 | Link to a section in other manual page. E.g., | |
357 | C<LE<lt>perlsyn/"For Loops"E<gt>> | |
358 | ||
359 | =item * | |
360 | ||
361 | C<LE<lt>/"sec"E<gt>> or C<LE<lt>/secE<gt>> or C<LE<lt>"sec"E<gt>> | |
362 | ||
363 | Link to a section in this manual page. E.g., | |
364 | C<LE<lt>/"Object Methods"E<gt>> | |
365 | ||
366 | =back | |
367 | ||
368 | A section is started by the named heading or item. For | |
369 | example, C<LE<lt>perlvar/$.E<gt>> or C<LE<lt>perlvar/"$."E<gt>> both | |
370 | link to the section started by "C<=item $.>" in perlvar. And | |
371 | C<LE<lt>perlsyn/For LoopsE<gt>> or C<LE<lt>perlsyn/"For Loops"E<gt>> | |
372 | both link to the section started by "C<=head2 For Loops>" | |
373 | in perlsyn. | |
374 | ||
375 | To control what text is used for display, you | |
376 | use "C<LE<lt>text|...E<gt>>", as in: | |
377 | ||
378 | =over | |
379 | ||
380 | =item * | |
381 | ||
382 | C<LE<lt>text|nameE<gt>> | |
383 | ||
384 | Link this text to that manual page. E.g., | |
385 | C<LE<lt>Perl Error Messages|perldiagE<gt>> | |
386 | ||
387 | =item * | |
388 | ||
389 | C<LE<lt>text|name/"sec"E<gt>> or C<LE<lt>text|name/secE<gt>> | |
390 | ||
391 | Link this text to that section in that manual page. E.g., | |
392 | C<LE<lt>SWITCH statements|perlsyn/"Basic BLOCKs and Switch | |
393 | Statements"E<gt>> | |
394 | ||
395 | =item * | |
396 | ||
397 | C<LE<lt>text|/"sec"E<gt>> or C<LE<lt>text|/secE<gt>> | |
398 | or C<LE<lt>text|"sec"E<gt>> | |
399 | ||
400 | Link this text to that section in this manual page. E.g., | |
401 | C<LE<lt>the various attributes|/"Member Data"E<gt>> | |
402 | ||
403 | =back | |
404 | ||
405 | Or you can link to a web page: | |
406 | ||
407 | =over | |
408 | ||
409 | =item * | |
410 | ||
411 | C<LE<lt>scheme:...E<gt>> | |
412 | ||
413 | Links to an absolute URL. For example, | |
414 | C<LE<lt>http://www.perl.org/E<gt>>. But note | |
415 | that there is no corresponding C<LE<lt>text|scheme:...E<gt>> syntax, for | |
416 | various reasons. | |
417 | ||
418 | =back | |
419 | ||
420 | =item C<EE<lt>escapeE<gt>> -- a character escape | |
421 | ||
422 | Very similar to HTML/XML C<&I<foo>;> "entity references": | |
423 | ||
424 | =over | |
425 | ||
426 | =item * | |
427 | ||
428 | C<EE<lt>ltE<gt>> -- a literal E<lt> (less than) | |
429 | ||
430 | =item * | |
431 | ||
432 | C<EE<lt>gtE<gt>> -- a literal E<gt> (greater than) | |
433 | ||
434 | =item * | |
435 | ||
436 | C<EE<lt>verbarE<gt>> -- a literal | (I<ver>tical I<bar>) | |
437 | ||
438 | =item * | |
439 | ||
440 | C<EE<lt>solE<gt>> = a literal / (I<sol>idus) | |
441 | ||
442 | The above four are optional except in other formatting codes, | |
443 | notably C<LE<lt>...E<gt>>, and when preceded by a | |
444 | capital letter. | |
445 | ||
446 | =item * | |
447 | ||
448 | C<EE<lt>htmlnameE<gt>> | |
449 | ||
450 | Some non-numeric HTML entity name, such as C<EE<lt>eacuteE<gt>>, | |
451 | meaning the same thing as C<é> in HTML -- i.e., a lowercase | |
452 | e with an acute (/-shaped) accent. | |
453 | ||
454 | =item * | |
455 | ||
456 | C<EE<lt>numberE<gt>> | |
457 | ||
458 | The ASCII/Latin-1/Unicode character with that number. A | |
459 | leading "0x" means that I<number> is hex, as in | |
460 | C<EE<lt>0x201EE<gt>>. A leading "0" means that I<number> is octal, | |
461 | as in C<EE<lt>075E<gt>>. Otherwise I<number> is interpreted as being | |
462 | in decimal, as in C<EE<lt>181E<gt>>. | |
463 | ||
464 | Note that older Pod formatters might not recognize octal or | |
465 | hex numeric escapes, and that many formatters cannot reliably | |
466 | render characters above 255. (Some formatters may even have | |
467 | to use compromised renderings of Latin-1 characters, like | |
468 | rendering C<EE<lt>eacuteE<gt>> as just a plain "e".) | |
469 | ||
470 | =back | |
471 | ||
472 | =item C<FE<lt>filenameE<gt>> -- used for filenames | |
473 | ||
474 | Typically displayed in italics. Example: "C<FE<lt>.cshrcE<gt>>" | |
475 | ||
476 | =item C<SE<lt>textE<gt>> -- text contains non-breaking spaces | |
477 | ||
478 | This means that the words in I<text> should not be broken | |
479 | across lines. Example: S<C<SE<lt>$x ? $y : $zE<gt>>>. | |
480 | ||
481 | =item C<XE<lt>topic nameE<gt>> -- an index entry | |
482 | ||
483 | This is ignored by most formatters, but some may use it for building | |
484 | indexes. It always renders as empty-string. | |
485 | Example: C<XE<lt>absolutizing relative URLsE<gt>> | |
486 | ||
487 | =item C<ZE<lt>E<gt>> -- a null (zero-effect) formatting code | |
488 | ||
489 | This is rarely used. It's one way to get around using an | |
490 | EE<lt>...E<gt> code sometimes. For example, instead of | |
491 | "C<NEE<lt>ltE<gt>3>" (for "NE<lt>3") you could write | |
492 | "C<NZE<lt>E<gt>E<lt>3>" (the "ZE<lt>E<gt>" breaks up the "N" and | |
493 | the "E<lt>" so they can't be considered | |
494 | the part of a (fictitious) "NE<lt>...E<gt>" code. | |
495 | ||
496 | =for comment | |
497 | This was formerly explained as a "zero-width character". But it in | |
498 | most parser models, it parses to nothing at all, as opposed to parsing | |
499 | as if it were a E<zwnj> or E<zwj>, which are REAL zero-width characters. | |
500 | So "width" and "character" are exactly the wrong words. | |
501 | ||
502 | =back | |
503 | ||
504 | Most of the time, you will need only a single set of angle brackets to | |
505 | delimit the beginning and end of formatting codes. However, | |
506 | sometimes you will want to put a real right angle bracket (a | |
507 | greater-than sign, '>') inside of a formatting code. This is particularly | |
508 | common when using a formatting code to provide a different font-type for a | |
509 | snippet of code. As with all things in Perl, there is more than | |
510 | one way to do it. One way is to simply escape the closing bracket | |
511 | using an C<E> code: | |
512 | ||
513 | C<$a E<lt>=E<gt> $b> | |
514 | ||
515 | This will produce: "C<$a E<lt>=E<gt> $b>" | |
516 | ||
517 | A more readable, and perhaps more "plain" way is to use an alternate | |
518 | set of delimiters that doesn't require a single ">" to be escaped. With | |
519 | the Pod formatters that are standard starting with perl5.5.660, doubled | |
520 | angle brackets ("<<" and ">>") may be used I<if and only if there is | |
521 | whitespace right after the opening delimiter and whitespace right | |
522 | before the closing delimiter!> For example, the following will | |
523 | do the trick: | |
524 | ||
525 | C<< $a <=> $b >> | |
526 | ||
527 | In fact, you can use as many repeated angle-brackets as you like so | |
528 | long as you have the same number of them in the opening and closing | |
529 | delimiters, and make sure that whitespace immediately follows the last | |
530 | '<' of the opening delimiter, and immediately precedes the first '>' | |
531 | of the closing delimiter. (The whitespace is ignored.) So the | |
532 | following will also work: | |
533 | ||
534 | C<<< $a <=> $b >>> | |
535 | C<<<< $a <=> $b >>>> | |
536 | ||
537 | And they all mean exactly the same as this: | |
538 | ||
539 | C<$a E<lt>=E<gt> $b> | |
540 | ||
541 | As a further example, this means that if you wanted to put these bits of | |
542 | code in C<C> (code) style: | |
543 | ||
544 | open(X, ">>thing.dat") || die $! | |
545 | $foo->bar(); | |
546 | ||
547 | you could do it like so: | |
548 | ||
549 | C<<< open(X, ">>thing.dat") || die $! >>> | |
550 | C<< $foo->bar(); >> | |
551 | ||
552 | which is presumably easier to read than the old way: | |
553 | ||
554 | C<open(X, "E<gt>E<gt>thing.dat") || die $!> | |
555 | C<$foo-E<gt>bar(); >> | |
556 | ||
557 | This is currently supported by pod2text (Pod::Text), pod2man (Pod::Man), | |
558 | and any other pod2xxx or Pod::Xxxx translators that use | |
559 | Pod::Parser 1.093 or later, or Pod::Tree 1.02 or later. | |
560 | ||
561 | =head2 The Intent | |
562 | ||
563 | The intent is simplicity of use, not power of expression. Paragraphs | |
564 | look like paragraphs (block format), so that they stand out | |
565 | visually, and so that I could run them through C<fmt> easily to reformat | |
566 | them (that's F7 in my version of B<vi>, or Esc Q in my version of | |
567 | B<emacs>). I wanted the translator to always leave the C<'> and C<`> and | |
568 | C<"> quotes alone, in verbatim mode, so I could slurp in a | |
569 | working program, shift it over four spaces, and have it print out, er, | |
570 | verbatim. And presumably in a monospace font. | |
571 | ||
572 | The Pod format is not necessarily sufficient for writing a book. Pod | |
573 | is just meant to be an idiot-proof common source for nroff, HTML, | |
574 | TeX, and other markup languages, as used for online | |
575 | documentation. Translators exist for B<pod2text>, B<pod2html>, | |
576 | B<pod2man> (that's for nroff(1) and troff(1)), B<pod2latex>, and | |
577 | B<pod2fm>. Various others are available in CPAN. | |
578 | ||
579 | ||
580 | =head2 Embedding Pods in Perl Modules | |
581 | ||
582 | You can embed Pod documentation in your Perl modules and scripts. | |
583 | Start your documentation with an empty line, a "=head1" command at the | |
584 | beginning, and end it with a "=cut" command and an empty line. Perl | |
585 | will ignore the Pod text. See any of the supplied library modules for | |
586 | examples. If you're going to put your Pod at the end of the file, and | |
587 | you're using an __END__ or __DATA__ cut mark, make sure to put an | |
588 | empty line there before the first Pod command. | |
589 | ||
590 | __END__ | |
591 | ||
592 | =head1 NAME | |
593 | ||
594 | Time::Local - efficiently compute time from local and GMT time | |
595 | ||
596 | Without that empty line before the "=head1", many translators wouldn't | |
597 | have recognized the "=head1" as starting a Pod block. | |
598 | ||
599 | =head2 Hints for Writing Pod | |
600 | ||
601 | =over | |
602 | ||
603 | =item * | |
604 | ||
605 | The B<podchecker> command is provided for checking Pod syntax for errors | |
606 | and warnings. For example, it checks for completely blank lines in | |
607 | Pod blocks and for unknown commands and formatting codes. You should | |
608 | still also pass your document through one or more translators and proofread | |
609 | the result, or print out the result and proofread that. Some of the | |
610 | problems found may be bugs in the translators, which you may or may not | |
611 | wish to work around. | |
612 | ||
613 | =item * | |
614 | ||
615 | If you're more familiar with writing in HTML than with writing in Pod, you | |
616 | can try your hand at writing documentation in simple HTML, and converting | |
617 | it to Pod with the experimental L<Pod::HTML2Pod|Pod::HTML2Pod> module, | |
618 | (available in CPAN), and looking at the resulting code. The experimental | |
619 | L<Pod::PXML|Pod::PXML> module in CPAN might also be useful. | |
620 | ||
621 | =item * | |
622 | ||
623 | Many older Pod translators require the lines before every Pod | |
624 | command and after every Pod command (including "=cut"!) to be a blank | |
625 | line. Having something like this: | |
626 | ||
627 | # - - - - - - - - - - - - | |
628 | =item $firecracker->boom() | |
629 | ||
630 | This noisily detonates the firecracker object. | |
631 | =cut | |
632 | sub boom { | |
633 | ... | |
634 | ||
635 | ...will make such Pod translators completely fail to see the Pod block | |
636 | at all. | |
637 | ||
638 | Instead, have it like this: | |
639 | ||
640 | # - - - - - - - - - - - - | |
641 | ||
642 | =item $firecracker->boom() | |
643 | ||
644 | This noisily detonates the firecracker object. | |
645 | ||
646 | =cut | |
647 | ||
648 | sub boom { | |
649 | ... | |
650 | ||
651 | =item * | |
652 | ||
653 | Some older Pod translators require paragraphs (including command | |
654 | paragraphs like "=head2 Functions") to be separated by I<completely> | |
655 | empty lines. If you have an apparently empty line with some spaces | |
656 | on it, this might not count as a separator for those translators, and | |
657 | that could cause odd formatting. | |
658 | ||
659 | =item * | |
660 | ||
661 | Older translators might add wording around an LE<lt>E<gt> link, so that | |
662 | C<LE<lt>Foo::BarE<gt>> may become "the Foo::Bar manpage", for example. | |
663 | So you shouldn't write things like C<the LE<lt>fooE<gt> | |
664 | documentation>, if you want the translated document to read sensibly | |
665 | -- instead write C<the LE<lt>Foo::Bar|Foo::BarE<gt> documentation> or | |
666 | C<LE<lt>the Foo::Bar documentation|Foo::BarE<gt>>, to control how the | |
667 | link comes out. | |
668 | ||
669 | =item * | |
670 | ||
671 | Going past the 70th column in a verbatim block might be ungracefully | |
672 | wrapped by some formatters. | |
673 | ||
674 | =back | |
675 | ||
676 | =head1 SEE ALSO | |
677 | ||
678 | L<perlpodspec>, L<perlsyn/"PODs: Embedded Documentation">, | |
679 | L<perlnewmod>, L<perldoc>, L<pod2html>, L<pod2man>, L<podchecker>. | |
680 | ||
681 | =head1 AUTHOR | |
682 | ||
683 | Larry Wall, Sean M. Burke | |
684 | ||
685 | =cut |