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1 | =head1 NAME |
2 | ||
3 | perlmodstyle - Perl module style guide | |
4 | ||
5 | =head1 INTRODUCTION | |
6 | ||
7 | This document attempts to describe the Perl Community's "best practice" | |
8 | for writing Perl modules. It extends the recommendations found in | |
9 | L<perlstyle> , which should be considered required reading | |
10 | before reading this document. | |
11 | ||
12 | While this document is intended to be useful to all module authors, it is | |
13 | particularly aimed at authors who wish to publish their modules on CPAN. | |
14 | ||
15 | The focus is on elements of style which are visible to the users of a | |
16 | module, rather than those parts which are only seen by the module's | |
17 | developers. However, many of the guidelines presented in this document | |
18 | can be extrapolated and applied successfully to a module's internals. | |
19 | ||
20 | This document differs from L<perlnewmod> in that it is a style guide | |
21 | rather than a tutorial on creating CPAN modules. It provides a | |
22 | checklist against which modules can be compared to determine whether | |
23 | they conform to best practice, without necessarily describing in detail | |
24 | how to achieve this. | |
25 | ||
26 | All the advice contained in this document has been gleaned from | |
27 | extensive conversations with experienced CPAN authors and users. Every | |
28 | piece of advice given here is the result of previous mistakes. This | |
29 | information is here to help you avoid the same mistakes and the extra | |
30 | work that would inevitably be required to fix them. | |
31 | ||
32 | The first section of this document provides an itemized checklist; | |
33 | subsequent sections provide a more detailed discussion of the items on | |
34 | the list. The final section, "Common Pitfalls", describes some of the | |
35 | most popular mistakes made by CPAN authors. | |
36 | ||
37 | =head1 QUICK CHECKLIST | |
38 | ||
39 | For more detail on each item in this checklist, see below. | |
40 | ||
41 | =head2 Before you start | |
42 | ||
43 | =over 4 | |
44 | ||
45 | =item * | |
46 | ||
47 | Don't re-invent the wheel | |
48 | ||
49 | =item * | |
50 | ||
51 | Patch, extend or subclass an existing module where possible | |
52 | ||
53 | =item * | |
54 | ||
55 | Do one thing and do it well | |
56 | ||
57 | =item * | |
58 | ||
59 | Choose an appropriate name | |
60 | ||
61 | =back | |
62 | ||
63 | =head2 The API | |
64 | ||
65 | =over 4 | |
66 | ||
67 | =item * | |
68 | ||
69 | API should be understandable by the average programmer | |
70 | ||
71 | =item * | |
72 | ||
73 | Simple methods for simple tasks | |
74 | ||
75 | =item * | |
76 | ||
77 | Separate functionality from output | |
78 | ||
79 | =item * | |
80 | ||
81 | Consistent naming of subroutines or methods | |
82 | ||
83 | =item * | |
84 | ||
85 | Use named parameters (a hash or hashref) when there are more than two | |
86 | parameters | |
87 | ||
88 | =back | |
89 | ||
90 | =head2 Stability | |
91 | ||
92 | =over 4 | |
93 | ||
94 | =item * | |
95 | ||
96 | Ensure your module works under C<use strict> and C<-w> | |
97 | ||
98 | =item * | |
99 | ||
100 | Stable modules should maintain backwards compatibility | |
101 | ||
102 | =back | |
103 | ||
104 | =head2 Documentation | |
105 | ||
106 | =over 4 | |
107 | ||
108 | =item * | |
109 | ||
110 | Write documentation in POD | |
111 | ||
112 | =item * | |
113 | ||
114 | Document purpose, scope and target applications | |
115 | ||
116 | =item * | |
117 | ||
118 | Document each publically accessible method or subroutine, including params and return values | |
119 | ||
120 | =item * | |
121 | ||
122 | Give examples of use in your documentation | |
123 | ||
124 | =item * | |
125 | ||
126 | Provide a README file and perhaps also release notes, changelog, etc | |
127 | ||
128 | =item * | |
129 | ||
130 | Provide links to further information (URL, email) | |
131 | ||
132 | =back | |
133 | ||
134 | =head2 Release considerations | |
135 | ||
136 | =over 4 | |
137 | ||
138 | =item * | |
139 | ||
140 | Specify pre-requisites in Makefile.PL | |
141 | ||
142 | =item * | |
143 | ||
144 | Specify Perl version requirements with C<use> | |
145 | ||
146 | =item * | |
147 | ||
148 | Include tests with your module | |
149 | ||
150 | =item * | |
151 | ||
152 | Choose a sensible and consistent version numbering scheme (X.YY is the common Perl module numbering scheme) | |
153 | ||
154 | =item * | |
155 | ||
156 | Increment the version number for every change, no matter how small | |
157 | ||
158 | =item * | |
159 | ||
160 | Package the module using "make dist" | |
161 | ||
162 | =item * | |
163 | ||
164 | Choose an appropriate license (GPL/Artistic is a good default) | |
165 | ||
166 | =back | |
167 | ||
168 | =head1 BEFORE YOU START WRITING A MODULE | |
169 | ||
170 | Try not to launch headlong into developing your module without spending | |
171 | some time thinking first. A little forethought may save you a vast | |
172 | amount of effort later on. | |
173 | ||
174 | =head2 Has it been done before? | |
175 | ||
176 | You may not even need to write the module. Check whether it's already | |
177 | been done in Perl, and avoid re-inventing the wheel unless you have a | |
178 | good reason. | |
179 | ||
180 | If an existing module B<almost> does what you want, consider writing a | |
181 | patch, writing a subclass, or otherwise extending the existing module | |
182 | rather than rewriting it. | |
183 | ||
184 | =head2 Do one thing and do it well | |
185 | ||
186 | At the risk of stating the obvious, modules are intended to be modular. | |
187 | A Perl developer should be able to use modules to put together the | |
188 | building blocks of their application. However, it's important that the | |
189 | blocks are the right shape, and that the developer shouldn't have to use | |
190 | a big block when all they need is a small one. | |
191 | ||
192 | Your module should have a clearly defined scope which is no longer than | |
193 | a single sentence. Can your module be broken down into a family of | |
194 | related modules? | |
195 | ||
196 | Bad example: | |
197 | ||
198 | "FooBar.pm provides an implementation of the FOO protocol and the | |
199 | related BAR standard." | |
200 | ||
201 | Good example: | |
202 | ||
203 | "Foo.pm provides an implementation of the FOO protocol. Bar.pm | |
204 | implements the related BAR protocol." | |
205 | ||
206 | This means that if a developer only needs a module for the BAR standard, | |
207 | they should not be forced to install libraries for FOO as well. | |
208 | ||
209 | =head2 What's in a name? | |
210 | ||
211 | Make sure you choose an appropriate name for your module early on. This | |
212 | will help people find and remember your module, and make programming | |
213 | with your module more intuitive. | |
214 | ||
215 | When naming your module, consider the following: | |
216 | ||
217 | =over 4 | |
218 | ||
219 | =item * | |
220 | ||
221 | Be descriptive (i.e. accurately describes the purpose of the module). | |
222 | ||
223 | =item * | |
224 | ||
225 | Be consistent with existing modules. | |
226 | ||
227 | =item * | |
228 | ||
229 | Reflect the functionality of the module, not the implementation. | |
230 | ||
231 | =item * | |
232 | ||
233 | Avoid starting a new top-level hierarchy, especially if a suitable | |
234 | hierarchy already exists under which you could place your module. | |
235 | ||
236 | =back | |
237 | ||
238 | You should contact modules@perl.org to ask them about your module name | |
239 | before publishing your module. You should also try to ask people who | |
240 | are already familiar with the module's application domain and the CPAN | |
241 | naming system. Authors of similar modules, or modules with similar | |
242 | names, may be a good place to start. | |
243 | ||
244 | =head1 DESIGNING AND WRITING YOUR MODULE | |
245 | ||
246 | Considerations for module design and coding: | |
247 | ||
248 | =head2 To OO or not to OO? | |
249 | ||
250 | Your module may be object oriented (OO) or not, or it may have both kinds | |
251 | of interfaces available. There are pros and cons of each technique, which | |
252 | should be considered when you design your API. | |
253 | ||
254 | According to Damian Conway, you should consider using OO: | |
255 | ||
256 | =over 4 | |
257 | ||
258 | =item * | |
259 | ||
260 | When the system is large or likely to become so | |
261 | ||
262 | =item * | |
263 | ||
264 | When the data is aggregated in obvious structures that will become objects | |
265 | ||
266 | =item * | |
267 | ||
268 | When the types of data form a natural hierarchy that can make use of inheritance | |
269 | ||
270 | =item * | |
271 | ||
272 | When operations on data vary according to data type (making | |
273 | polymorphic invocation of methods feasible) | |
274 | ||
275 | =item * | |
276 | ||
277 | When it is likely that new data types may be later introduced | |
278 | into the system, and will need to be handled by existing code | |
279 | ||
280 | =item * | |
281 | ||
282 | When interactions between data are best represented by | |
283 | overloaded operators | |
284 | ||
285 | =item * | |
286 | ||
287 | When the implementation of system components is likely to | |
288 | change over time (and hence should be encapsulated) | |
289 | ||
290 | =item * | |
291 | ||
292 | When the system design is itself object-oriented | |
293 | ||
294 | =item * | |
295 | ||
296 | When large amounts of client code will use the software (and | |
297 | should be insulated from changes in its implementation) | |
298 | ||
299 | =item * | |
300 | ||
301 | When many separate operations will need to be applied to the | |
302 | same set of data | |
303 | ||
304 | =back | |
305 | ||
306 | Think carefully about whether OO is appropriate for your module. | |
307 | Gratuitous object orientation results in complex APIs which are | |
308 | difficult for the average module user to understand or use. | |
309 | ||
310 | =head2 Designing your API | |
311 | ||
312 | Your interfaces should be understandable by an average Perl programmer. | |
313 | The following guidelines may help you judge whether your API is | |
314 | sufficiently straightforward: | |
315 | ||
316 | =over 4 | |
317 | ||
318 | =item Write simple routines to do simple things. | |
319 | ||
320 | It's better to have numerous simple routines than a few monolithic ones. | |
321 | If your routine changes its behaviour significantly based on its | |
322 | arguments, it's a sign that you should have two (or more) separate | |
323 | routines. | |
324 | ||
325 | =item Separate functionality from output. | |
326 | ||
327 | Return your results in the most generic form possible and allow the user | |
328 | to choose how to use them. The most generic form possible is usually a | |
329 | Perl data structure which can then be used to generate a text report, | |
330 | HTML, XML, a database query, or whatever else your users require. | |
331 | ||
332 | If your routine iterates through some kind of list (such as a list of | |
333 | files, or records in a database) you may consider providing a callback | |
334 | so that users can manipulate each element of the list in turn. | |
335 | File::Find provides an example of this with its | |
336 | C<find(\&wanted, $dir)> syntax. | |
337 | ||
338 | =item Provide sensible shortcuts and defaults. | |
339 | ||
340 | Don't require every module user to jump through the same hoops to achieve a | |
341 | simple result. You can always include optional parameters or routines for | |
342 | more complex or non-standard behaviour. If most of your users have to | |
343 | type a few almost identical lines of code when they start using your | |
344 | module, it's a sign that you should have made that behaviour a default. | |
345 | Another good indicator that you should use defaults is if most of your | |
346 | users call your routines with the same arguments. | |
347 | ||
348 | =item Naming conventions | |
349 | ||
350 | Your naming should be consistent. For instance, it's better to have: | |
351 | ||
352 | display_day(); | |
353 | display_week(); | |
354 | display_year(); | |
355 | ||
356 | than | |
357 | ||
358 | display_day(); | |
359 | week_display(); | |
360 | show_year(); | |
361 | ||
362 | This applies equally to method names, parameter names, and anything else | |
363 | which is visible to the user (and most things that aren't!) | |
364 | ||
365 | =item Parameter passing | |
366 | ||
367 | Use named parameters. It's easier to use a hash like this: | |
368 | ||
369 | $obj->do_something( | |
370 | name => "wibble", | |
371 | type => "text", | |
372 | size => 1024, | |
373 | ); | |
374 | ||
375 | ... than to have a long list of unnamed parameters like this: | |
376 | ||
377 | $obj->do_something("wibble", "text", 1024); | |
378 | ||
379 | While the list of arguments might work fine for one, two or even three | |
380 | arguments, any more arguments become hard for the module user to | |
381 | remember, and hard for the module author to manage. If you want to add | |
382 | a new parameter you will have to add it to the end of the list for | |
383 | backward compatibility, and this will probably make your list order | |
384 | unintuitive. Also, if many elements may be undefined you may see the | |
385 | following unattractive method calls: | |
386 | ||
387 | $obj->do_something(undef, undef, undef, undef, undef, undef, 1024); | |
388 | ||
389 | Provide sensible defaults for parameters which have them. Don't make | |
390 | your users specify parameters which will almost always be the same. | |
391 | ||
392 | The issue of whether to pass the arguments in a hash or a hashref is | |
393 | largely a matter of personal style. | |
394 | ||
395 | The use of hash keys starting with a hyphen (C<-name>) or entirely in | |
396 | upper case (C<NAME>) is a relic of older versions of Perl in which | |
397 | ordinary lower case strings were not handled correctly by the C<=E<gt>> | |
398 | operator. While some modules retain uppercase or hyphenated argument | |
399 | keys for historical reasons or as a matter of personal style, most new | |
400 | modules should use simple lower case keys. Whatever you choose, be | |
401 | consistent! | |
402 | ||
403 | =back | |
404 | ||
405 | =head2 Strictness and warnings | |
406 | ||
407 | Your module should run successfully under the strict pragma and should | |
408 | run without generating any warnings. Your module should also handle | |
409 | taint-checking where appropriate, though this can cause difficulties in | |
410 | many cases. | |
411 | ||
412 | =head2 Backwards compatibility | |
413 | ||
414 | Modules which are "stable" should not break backwards compatibility | |
415 | without at least a long transition phase and a major change in version | |
416 | number. | |
417 | ||
418 | =head2 Error handling and messages | |
419 | ||
420 | When your module encounters an error it should do one or more of: | |
421 | ||
422 | =over 4 | |
423 | ||
424 | =item * | |
425 | ||
426 | Return an undefined value. | |
427 | ||
428 | =item * | |
429 | ||
430 | set C<$Module::errstr> or similar (C<errstr> is a common name used by | |
431 | DBI and other popular modules; if you choose something else, be sure to | |
432 | document it clearly). | |
433 | ||
434 | =item * | |
435 | ||
436 | C<warn()> or C<carp()> a message to STDERR. | |
437 | ||
438 | =item * | |
439 | ||
440 | C<croak()> only when your module absolutely cannot figure out what to | |
441 | do. (C<croak()> is a better version of C<die()> for use within | |
442 | modules, which reports its errors from the perspective of the caller. | |
443 | See L<Carp> for details of C<croak()>, C<carp()> and other useful | |
444 | routines.) | |
445 | ||
446 | =item * | |
447 | ||
448 | As an alternative to the above, you may prefer to throw exceptions using | |
449 | the Error module. | |
450 | ||
451 | =back | |
452 | ||
453 | Configurable error handling can be very useful to your users. Consider | |
454 | offering a choice of levels for warning and debug messages, an option to | |
455 | send messages to a separate file, a way to specify an error-handling | |
456 | routine, or other such features. Be sure to default all these options | |
457 | to the commonest use. | |
458 | ||
459 | =head1 DOCUMENTING YOUR MODULE | |
460 | ||
461 | =head2 POD | |
462 | ||
463 | Your module should include documentation aimed at Perl developers. | |
464 | You should use Perl's "plain old documentation" (POD) for your general | |
465 | technical documentation, though you may wish to write additional | |
466 | documentation (white papers, tutorials, etc) in some other format. | |
467 | You need to cover the following subjects: | |
468 | ||
469 | =over 4 | |
470 | ||
471 | =item * | |
472 | ||
473 | A synopsis of the common uses of the module | |
474 | ||
475 | =item * | |
476 | ||
477 | The purpose, scope and target applications of your module | |
478 | ||
479 | =item * | |
480 | ||
481 | Use of each publically accessible method or subroutine, including | |
482 | parameters and return values | |
483 | ||
484 | =item * | |
485 | ||
486 | Examples of use | |
487 | ||
488 | =item * | |
489 | ||
490 | Sources of further information | |
491 | ||
492 | =item * | |
493 | ||
494 | A contact email address for the author/maintainer | |
495 | ||
496 | =back | |
497 | ||
498 | The level of detail in Perl module documentation generally goes from | |
499 | less detailed to more detailed. Your SYNOPSIS section should contain a | |
500 | minimal example of use (perhaps as little as one line of code; skip the | |
da75cd15 | 501 | unusual use cases or anything not needed by most users); the |
f67486be KR |
502 | DESCRIPTION should describe your module in broad terms, generally in |
503 | just a few paragraphs; more detail of the module's routines or methods, | |
504 | lengthy code examples, or other in-depth material should be given in | |
505 | subsequent sections. | |
506 | ||
507 | Ideally, someone who's slightly familiar with your module should be able | |
508 | to refresh their memory without hitting "page down". As your reader | |
509 | continues through the document, they should receive a progressively | |
510 | greater amount of knowledge. | |
511 | ||
512 | The recommended order of sections in Perl module documentation is: | |
513 | ||
514 | =over 4 | |
515 | ||
516 | =item * | |
517 | ||
518 | NAME | |
519 | ||
520 | =item * | |
521 | ||
522 | SYNOPSIS | |
523 | ||
524 | =item * | |
525 | ||
526 | DESCRIPTION | |
527 | ||
528 | =item * | |
529 | ||
530 | One or more sections or subsections giving greater detail of available | |
531 | methods and routines and any other relevant information. | |
532 | ||
533 | =item * | |
534 | ||
535 | BUGS/CAVEATS/etc | |
536 | ||
537 | =item * | |
538 | ||
539 | AUTHOR | |
540 | ||
541 | =item * | |
542 | ||
543 | SEE ALSO | |
544 | ||
545 | =item * | |
546 | ||
547 | COPYRIGHT and LICENSE | |
548 | ||
549 | =back | |
550 | ||
551 | Keep your documentation near the code it documents ("inline" | |
552 | documentation). Include POD for a given method right above that | |
553 | method's subroutine. This makes it easier to keep the documentation up | |
554 | to date, and avoids having to document each piece of code twice (once in | |
555 | POD and once in comments). | |
556 | ||
557 | =head2 README, INSTALL, release notes, changelogs | |
558 | ||
559 | Your module should also include a README file describing the module and | |
560 | giving pointers to further information (website, author email). | |
561 | ||
562 | An INSTALL file should be included, and should contain simple installation | |
563 | instructions (usually "perl Makefile.PL; make; make install"). | |
564 | ||
565 | Release notes or changelogs should be produced for each release of your | |
566 | software describing user-visible changes to your module, in terms | |
567 | relevant to the user. | |
568 | ||
569 | =head1 RELEASE CONSIDERATIONS | |
570 | ||
571 | =head2 Version numbering | |
572 | ||
573 | Version numbers should indicate at least major and minor releases, and | |
574 | possibly sub-minor releases. A major release is one in which most of | |
575 | the functionality has changed, or in which major new functionality is | |
576 | added. A minor release is one in which a small amount of functionality | |
577 | has been added or changed. Sub-minor version numbers are usually used | |
578 | for changes which do not affect functionality, such as documentation | |
579 | patches. | |
580 | ||
581 | The most common CPAN version numbering scheme looks like this: | |
582 | ||
583 | 1.00, 1.10, 1.11, 1.20, 1.30, 1.31, 1.32 | |
584 | ||
585 | A correct CPAN version number is a floating point number with at least | |
586 | 2 digits after the decimal. You can test whether it conforms to CPAN by | |
587 | using | |
588 | ||
589 | perl -MExtUtils::MakeMaker -le 'print MM->parse_version(shift)' 'Foo.pm' | |
590 | ||
591 | If you want to release a 'beta' or 'alpha' version of a module but don't | |
592 | want CPAN.pm to list it as most recent use an '_' after the regular | |
593 | version number followed by at least 2 digits, eg. 1.20_01 | |
594 | ||
595 | Never release anything (even a one-word documentation patch) without | |
596 | incrementing the number. Even a one-word documentation patch should | |
597 | result in a change in version at the sub-minor level. | |
598 | ||
599 | =head2 Pre-requisites | |
600 | ||
601 | Module authors should carefully consider whether to rely on other | |
602 | modules, and which modules to rely on. | |
603 | ||
604 | Most importantly, choose modules which are as stable as possible. In | |
605 | order of preference: | |
606 | ||
607 | =over 4 | |
608 | ||
609 | =item * | |
610 | ||
611 | Core Perl modules | |
612 | ||
613 | =item * | |
614 | ||
615 | Stable CPAN modules | |
616 | ||
617 | =item * | |
618 | ||
619 | Unstable CPAN modules | |
620 | ||
621 | =item * | |
622 | ||
623 | Modules not available from CPAN | |
624 | ||
625 | =back | |
626 | ||
627 | Specify version requirements for other Perl modules in the | |
628 | pre-requisites in your Makefile.PL. | |
629 | ||
630 | Be sure to specify Perl version requirements both in Makefile.PL and | |
631 | with C<require 5.6.1> or similar. | |
632 | ||
633 | =head2 Testing | |
634 | ||
635 | All modules should be tested before distribution (using "make disttest", | |
636 | and the tests should also be available to people installing the modules | |
637 | (using "make test"). | |
638 | ||
639 | The importance of these tests is proportional to the alleged stability of a | |
640 | module -- a module which purports to be stable or which hopes to achieve wide | |
641 | use should adhere to as strict a testing regime as possible. | |
642 | ||
643 | Useful modules to help you write tests (with minimum impact on your | |
644 | development process or your time) include Test::Simple, Carp::Assert | |
645 | and Test::Inline. | |
646 | ||
647 | =head2 Packaging | |
648 | ||
649 | Modules should be packaged using the standard MakeMaker tools, allowing | |
650 | them to be installed in a consistent manner. Use "make dist" to create | |
651 | your package. | |
652 | ||
653 | Tools exist to help you build your module in a MakeMaker-friendly style. | |
654 | These include ExtUtils::ModuleMaker and h2xs. See also L<perlnewmod>. | |
655 | ||
656 | =head2 Licensing | |
657 | ||
658 | Make sure that your module has a license, and that the full text of it | |
659 | is included in the distribution (unless it's a common one and the terms | |
660 | of the license don't require you to include it). | |
661 | ||
662 | If you don't know what license to use, dual licensing under the GPL | |
663 | and Artistic licenses (the same as Perl itself) is a good idea. | |
664 | ||
665 | =head1 COMMON PITFALLS | |
666 | ||
667 | =head2 Reinventing the wheel | |
668 | ||
669 | There are certain application spaces which are already very, very well | |
670 | served by CPAN. One example is templating systems, another is date and | |
671 | time modules, and there are many more. While it is a rite of passage to | |
672 | write your own version of these things, please consider carefully | |
673 | whether the Perl world really needs you to publish it. | |
674 | ||
675 | =head2 Trying to do too much | |
676 | ||
677 | Your module will be part of a developer's toolkit. It will not, in | |
678 | itself, form the B<entire> toolkit. It's tempting to add extra features | |
679 | until your code is a monolithic system rather than a set of modular | |
680 | building blocks. | |
681 | ||
682 | =head2 Inappropriate documentation | |
683 | ||
684 | Don't fall into the trap of writing for the wrong audience. Your | |
685 | primary audience is a reasonably experienced developer with at least | |
686 | a moderate understanding of your module's application domain, who's just | |
687 | downloaded your module and wants to start using it as quickly as possible. | |
688 | ||
689 | Tutorials, end-user documentation, research papers, FAQs etc are not | |
690 | appropriate in a module's main documentation. If you really want to | |
691 | write these, include them as sub-documents such as C<My::Module::Tutorial> or | |
692 | C<My::Module::FAQ> and provide a link in the SEE ALSO section of the | |
693 | main documentation. | |
694 | ||
695 | =head1 SEE ALSO | |
696 | ||
697 | =over 4 | |
698 | ||
699 | =item L<perlstyle> | |
700 | ||
701 | General Perl style guide | |
702 | ||
703 | =item L<perlnewmod> | |
704 | ||
705 | How to create a new module | |
706 | ||
707 | =item L<perlpod> | |
708 | ||
709 | POD documentation | |
710 | ||
711 | =item L<podchecker> | |
712 | ||
713 | Verifies your POD's correctness | |
714 | ||
715 | =item Testing tools | |
716 | ||
717 | L<Test::Simple>, L<Test::Inline>, L<Carp::Assert> | |
718 | ||
719 | =item http://pause.perl.org/ | |
720 | ||
721 | Perl Authors Upload Server. Contains links to information for module | |
722 | authors. | |
723 | ||
724 | =item Any good book on software engineering | |
725 | ||
726 | =back | |
727 | ||
728 | =head1 AUTHOR | |
729 | ||
730 | Kirrily "Skud" Robert <skud@cpan.org> | |
731 |