5 open (OUT, ">perlmodlib.tmp") or die $!;
6 my (@pragma, @mod, @MANIFEST);
7 open (MANIFEST, "../MANIFEST") or die $!;
11 next unless s|^lib/|| or m|^ext/|;
12 ($filename) = m|^(\S+)|;
13 $filename =~ s|^[^/]+/|| if $filename =~ s|^ext/||;
14 next unless $filename =~ m!\.p(m|od)$!;
15 next unless open (MOD, "../lib/$filename");
23 next unless /^=head1 NAME/;
29 warn "$filename missing =head1 NAME (okay if there is respective .pod)\n";
36 my $perlname = $filename;
37 $perlname =~ s!\.p(m|od)$!!;
38 $perlname =~ s!/!::!g;
40 ($name, $thing) = split / --? /, $title, 2;
42 unless ($name and $thing) {
43 warn "$filename missing name\n" unless $name;
44 warn "$filename missing thing\n" unless $thing;
49 $thing =~ s/^perl pragma to //i;
50 $thing = ucfirst($thing);
51 $title = "=item $perlname\n\n$thing\n\n";
53 if ($filename =~ /[A-Z]/) {
62 Generated by perlmodlib.PL -- DO NOT EDIT!
66 perlmodlib - constructing new Perl modules and finding existing ones
70 =head1 THE PERL MODULE LIBRARY
72 Many modules are included the Perl distribution. These are described
73 below, and all end in F<.pm>. You may discover compiled library
74 file (usually ending in F<.so>) or small pieces of modules to be
75 autoloaded (ending in F<.al>); these were automatically generated
76 by the installation process. You may also discover files in the
77 library directory that end in either F<.pl> or F<.ph>. These are
78 old libraries supplied so that old programs that use them still
79 run. The F<.pl> files will all eventually be converted into standard
80 modules, and the F<.ph> files made by B<h2ph> will probably end up
81 as extension modules made by B<h2xs>. (Some F<.ph> values may
82 already be available through the POSIX, Errno, or Fcntl modules.)
83 The B<pl2pm> file in the distribution may help in your conversion,
84 but it's just a mechanical process and therefore far from bulletproof.
86 =head2 Pragmatic Modules
88 They work somewhat like compiler directives (pragmata) in that they
89 tend to affect the compilation of your program, and thus will usually
90 work well only when used within a C<use>, or C<no>. Most of these
91 are lexically scoped, so an inner BLOCK may countermand them
98 which lasts until the end of that BLOCK.
100 Some pragmas are lexically scoped--typically those that affect the
101 C<$^H> hints variable. Others affect the current package instead,
102 like C<use vars> and C<use subs>, which allow you to predeclare a
103 variables or subroutines within a particular I<file> rather than
104 just a block. Such declarations are effective for the entire file
105 for which they were declared. You cannot rescind them with C<no
108 The following pragmas are defined (and have their own documentation).
114 print OUT $_ for (sort @pragma);
119 =head2 Standard Modules
121 Standard, bundled modules are all expected to behave in a well-defined
122 manner with respect to namespace pollution because they use the
123 Exporter module. See their own documentation for details.
129 print OUT $_ for (sort @mod);
134 To find out I<all> modules installed on your system, including
135 those without documentation or outside the standard release,
138 % find `perl -e 'print "@INC"'` -name '*.pm' -print
140 They should all have their own documentation installed and accessible
141 via your system man(1) command. If you do not have a B<find>
142 program, you can use the Perl B<find2perl> program instead, which
143 generates Perl code as output you can run through perl. If you
144 have a B<man> program but it doesn't find your modules, you'll have
145 to fix your manpath. See L<perl> for details. If you have no
146 system B<man> command, you might try the B<perldoc> program.
148 =head2 Extension Modules
150 Extension modules are written in C (or a mix of Perl and C). They
151 are usually dynamically loaded into Perl if and when you need them,
152 but may also be linked in statically. Supported extension modules
153 include Socket, Fcntl, and POSIX.
155 Many popular C extension modules do not come bundled (at least, not
156 completely) due to their sizes, volatility, or simply lack of time
157 for adequate testing and configuration across the multitude of
158 platforms on which Perl was beta-tested. You are encouraged to
159 look for them on CPAN (described below), or using web search engines
160 like Alta Vista or Deja News.
164 CPAN stands for Comprehensive Perl Archive Network; it's a globally
165 replicated trove of Perl materials, including documentation, style
166 guides, tricks and traps, alternate ports to non-Unix systems and
167 occasional binary distributions for these. Search engines for
168 CPAN can be found at http://www.cpan.org/
170 Most importantly, CPAN includes around a thousand unbundled modules,
171 some of which require a C compiler to build. Major categories of
178 Language Extensions and Documentation Tools
186 Operating System Interfaces
190 Networking, Device Control (modems) and InterProcess Communication
194 Data Types and Data Type Utilities
206 Interfaces to / Emulations of Other Programming Languages
210 File Names, File Systems and File Locking (see also File Handles)
214 String Processing, Language Text Processing, Parsing, and Searching
218 Option, Argument, Parameter, and Configuration File Processing
222 Internationalization and Locale
226 Authentication, Security, and Encryption
230 World Wide Web, HTML, HTTP, CGI, MIME
234 Server and Daemon Utilities
238 Archiving and Compression
242 Images, Pixmap and Bitmap Manipulation, Drawing, and Graphing
250 Control Flow Utilities (callbacks and exceptions etc)
254 File Handle and Input/Output Stream Utilities
258 Miscellaneous Modules
262 Registered CPAN sites as of this writing include the following.
263 You should try to choose one close to you:
273 ftp://ftp.is.co.za/programming/perl/CPAN/
274 ftp://ftp.mweb.co.za/pub/mirrors/cpan/
275 ftp://ftp.saix.net/pub/CPAN/
276 ftp://ftp.sun.ac.za/CPAN/CPAN/
288 ftp://freesoft.cei.gov.cn/pub/languages/perl/CPAN/
289 http://www2.linuxforum.net/mirror/CPAN/
290 http://cpan.shellhung.org/
291 ftp://ftp.shellhung.org/pub/CPAN
297 http://cpan.in.freeos.com
298 ftp://cpan.in.freeos.com/pub/CPAN/
304 http://cpan.itb.web.id/
305 ftp://mirrors.piksi.itb.ac.id/CPAN/
306 http://CPAN.mweb.co.id/
307 ftp://ftp.mweb.co.id/pub/languages/perl/CPAN/
313 http://www.iglu.org.il:/pub/CPAN/
314 ftp://ftp.iglu.org.il/pub/CPAN/
315 http://cpan.lerner.co.il/
316 http://bioinfo.weizmann.ac.il/pub/software/perl/CPAN/
317 ftp://bioinfo.weizmann.ac.il/pub/software/perl/CPAN/
323 ftp://ftp.u-aizu.ac.jp/pub/CPAN
324 ftp://ftp.kddlabs.co.jp/CPAN/
325 http://mirror.nucba.ac.jp/mirror/Perl/
326 ftp://mirror.nucba.ac.jp/mirror/Perl/
327 ftp://ftp.meisei-u.ac.jp/pub/CPAN/
328 ftp://ftp.ayamura.org/pub/CPAN/
329 ftp://ftp.jaist.ac.jp/pub/lang/perl/CPAN/
330 ftp://ftp.dti.ad.jp/pub/lang/CPAN/
331 ftp://ftp.ring.gr.jp/pub/lang/perl/CPAN/
337 http://mirror.Mazic.org/pub/CPAN
338 ftp://mirror.Mazic.org/pub/CPAN
344 http://www.adzu.edu.ph/CPAN
351 ftp://cpan.tomsk.ru/pub/CPAN
357 ftp://ftp.isu.net.sa/pub/CPAN/
363 http://cpan.hjc.edu.sg
369 http://CPAN.bora.net/
370 ftp://ftp.bora.net/pub/CPAN/
371 http://ftp.kornet.net/pub/CPAN/
372 ftp://ftp.kornet.net/pub/CPAN/
373 ftp://ftp.nuri.net/pub/CPAN/
374 http://ftp.xgate.co.kr/cpan/
375 ftp://ftp.xgate.co.kr/pub/mirror/CPAN
381 ftp://ftp.ee.ncku.edu.tw/pub/perl/CPAN/
382 ftp://ftp1.sinica.edu.tw/pub1/perl/CPAN/
383 http://ftp.tku.edu.tw/pub/CPAN/
384 ftp://ftp.tku.edu.tw/pub/CPAN/
390 ftp://ftp.cs.riubon.ac.th/pub/mirrors/CPAN/
394 =head2 Central America
402 ftp://ftp.linux.co.cr/mirrors/CPAN/
403 http://ftp.ucr.ac.cr/Unix/CPAN/
404 ftp://ftp.ucr.ac.cr/pub/Unix/CPAN/
416 ftp://ftp.tuwien.ac.at/pub/CPAN/
422 http://ftp.easynet.be/pub/CPAN/
423 ftp://ftp.easynet.be/pub/CPAN/
424 http://cpan.skynet.be
425 ftp://ftp.skynet.be/pub/CPAN
426 ftp://ftp.kulnet.kuleuven.ac.be/pub/mirror/CPAN/
432 http://cpan.lirex.net/
433 ftp://ftp.lirex.net/pub/mirrors/CPAN
439 ftp://ftp.linux.hr/pub/CPAN/
445 http://ftp.fi.muni.cz/pub/CPAN/
446 ftp://ftp.fi.muni.cz/pub/CPAN/
447 ftp://sunsite.mff.cuni.cz/MIRRORS/ftp.funet.fi/pub/languages/perl/CPAN/
453 http://mirrors.sunsite.dk/cpan/
454 ftp://sunsite.dk/mirrors/cpan/
455 http://www.cpan.dk/CPAN/
456 ftp://www.cpan.dk/ftp.cpan.org/CPAN/
462 ftp://ftp.ut.ee/pub/languages/perl/CPAN/
468 ftp://ftp.funet.fi/pub/languages/perl/CPAN/
469 http://cpan.kpnqwest.fi/
475 http://cpan.mirrors.easynet.fr/
476 ftp://cpan.mirrors.easynet.fr/pub/ftp.cpan.org/
477 ftp://ftp.club-internet.fr/pub/perl/CPAN/
479 ftp://ftp.lip6.fr/pub/perl/CPAN/
480 ftp://ftp.oleane.net/pub/mirrors/CPAN/
481 ftp://ftp.pasteur.fr/pub/computing/CPAN/
483 ftp://cpan.cict.fr/pub/CPAN/
484 ftp://ftp.uvsq.fr/pub/perl/CPAN/
490 ftp://ftp.rz.ruhr-uni-bochum.de/pub/CPAN/
491 ftp://ftp.freenet.de/pub/ftp.cpan.org/pub/CPAN/
492 ftp://ftp.uni-erlangen.de/pub/source/CPAN/
493 ftp://ftp-stud.fht-esslingen.de/pub/Mirrors/CPAN
494 ftp://ftp.gigabell.net/pub/CPAN/
495 http://pandemonium.tiscali.de/pub/CPAN/
496 ftp://pandemonium.tiscali.de/pub/CPAN/
497 http://ftp.gwdg.de/pub/languages/perl/CPAN/
498 ftp://ftp.gwdg.de/pub/languages/perl/CPAN/
499 ftp://ftp.uni-hamburg.de/pub/soft/lang/perl/CPAN/
500 ftp://ftp.leo.org/pub/CPAN/
501 http://cpan.noris.de/
502 ftp://cpan.noris.de/pub/CPAN/
503 ftp://ftp.mpi-sb.mpg.de/pub/perl/CPAN/
504 ftp://ftp.gmd.de/mirrors/CPAN/
510 ftp://ftp.acn.gr/pub/lang/perl/CPAN
511 ftp://ftp.forthnet.gr/pub/languages/perl/CPAN
512 ftp://ftp.ntua.gr/pub/lang/perl/
518 http://cpan.artifact.hu/
519 ftp://cpan.artifact.hu/CPAN/
520 http://ftp.kfki.hu/packages/perl/CPAN/
521 ftp://ftp.kfki.hu/pub/packages/perl/CPAN/
527 http://ftp.rhnet.is/pub/CPAN/
528 ftp://ftp.rhnet.is/pub/CPAN/
534 http://cpan.indigo.ie/
535 ftp://cpan.indigo.ie/pub/CPAN/
536 http://sunsite.compapp.dcu.ie/pub/perl/
537 ftp://sunsite.compapp.dcu.ie/pub/perl/
543 http://cpan.nettuno.it/
544 http://gusp.dyndns.org/CPAN/
545 ftp://gusp.dyndns.org/pub/CPAN
546 http://softcity.iol.it/cpan
547 ftp://softcity.iol.it/pub/cpan
548 ftp://ftp.unina.it/pub/Other/CPAN/CPAN/
549 ftp://ftp.unipi.it/pub/mirror/perl/CPAN/
550 ftp://cis.uniRoma2.it/CPAN/
551 ftp://ftp.edisontel.it/pub/CPAN_Mirror/
552 ftp://ftp.flashnet.it/pub/CPAN/
558 http://kvin.lv/pub/CPAN/
564 ftp://ftp.unix.lt/pub/CPAN/
570 ftp://download.xs4all.nl/pub/mirror/CPAN/
571 ftp://ftp.nl.uu.net/pub/CPAN/
572 ftp://ftp.nluug.nl/pub/languages/perl/CPAN/
573 ftp://ftp.cpan.nl/pub/CPAN/
574 http://www.cs.uu.nl/mirror/CPAN/
575 ftp://ftp.cs.uu.nl/mirror/CPAN/
581 ftp://ftp.uninett.no/pub/languages/perl/CPAN
582 ftp://ftp.uit.no/pub/languages/perl/cpan/
588 ftp://ftp.pk.edu.pl/pub/lang/perl/CPAN/
589 ftp://ftp.mega.net.pl/pub/mirrors/ftp.perl.com/
590 ftp://ftp.man.torun.pl/pub/doc/CPAN/
591 ftp://sunsite.icm.edu.pl/pub/CPAN/
597 ftp://ftp.ua.pt/pub/CPAN/
598 ftp://perl.di.uminho.pt/pub/CPAN/
599 http://cpan.dei.uc.pt/
600 ftp://ftp.dei.uc.pt/pub/CPAN
601 ftp://ftp.ist.utl.pt/pub/CPAN/
603 ftp://cpan.ip.pt/pub/cpan/
604 ftp://ftp.netc.pt/pub/CPAN/
605 ftp://ftp.up.pt/pub/CPAN
611 ftp://ftp.kappa.ro/pub/mirrors/ftp.perl.org/pub/CPAN/
612 ftp://ftp.dntis.ro/pub/cpan/
613 ftp://ftp.dnttm.ro/pub/CPAN/
614 ftp://ftp.lasting.ro/pub/CPAN
615 ftp://ftp.timisoara.roedu.net/mirrors/CPAN/
621 ftp://ftp.chg.ru/pub/lang/perl/CPAN/
622 http://cpan.rinet.ru/
623 ftp://cpan.rinet.ru/pub/mirror/CPAN/
624 ftp://ftp.aha.ru/pub/CPAN/
625 http://cpan.sai.msu.ru/
626 ftp://ftp.sai.msu.su/pub/lang/perl/CPAN/
632 http://ftp.cvt.stuba.sk/pub/CPAN/
633 ftp://ftp.cvt.stuba.sk/pub/CPAN/
639 ftp://ftp.arnes.si/software/perl/CPAN/
645 http://cpan.imasd.elmundo.es/
646 ftp://ftp.rediris.es/mirror/CPAN/
647 ftp://ftp.etse.urv.es/pub/perl/
653 http://ftp.du.se/CPAN/
654 ftp://ftp.du.se/pub/CPAN/
655 ftp://mirror.dataphone.se/pub/CPAN
656 ftp://ftp.sunet.se/pub/lang/perl/CPAN/
662 ftp://ftp.danyk.ch/CPAN/
663 ftp://sunsite.cnlab-switch.ch/mirror/CPAN/
669 ftp://sunsite.bilkent.edu.tr/pub/languages/CPAN/
677 ftp://ftp.perl.org.ua/pub/CPAN/
683 http://www.mirror.ac.uk/sites/ftp.funet.fi/pub/languages/perl/CPAN
684 ftp://ftp.mirror.ac.uk/sites/ftp.funet.fi/pub/languages/perl/CPAN/
685 http://cpan.teleglobe.net/
686 ftp://cpan.teleglobe.net/pub/CPAN
687 http://cpan.crazygreek.co.uk
688 ftp://ftp.demon.co.uk/pub/CPAN/
689 ftp://ftp.flirble.org/pub/languages/perl/CPAN/
690 ftp://ftp.plig.org/pub/CPAN/
691 http://mirror.uklinux.net/CPAN/
692 ftp://mirror.uklinux.net/pub/CPAN/
693 http://cpan.mirrors.clockerz.net/
694 ftp://ftp.clockerz.net/pub/CPAN/
695 ftp://usit.shef.ac.uk/pub/packages/CPAN/
713 http://sunsite.ualberta.ca/pub/Mirror/CPAN/
714 ftp://sunsite.ualberta.ca/pub/Mirror/CPAN/
720 http://theoryx5.uwinnipeg.ca/pub/CPAN/
721 ftp://theoryx5.uwinnipeg.ca/pub/CPAN/
727 ftp://cpan.chebucto.ns.ca/pub/CPAN/
733 ftp://ftp.crc.ca/pub/CPAN/
739 http://cpan.mirror.smartworker.org/
747 http://cpan.azc.uam.mx
748 ftp://cpan.azc.uam.mx/mirrors/CPAN
750 ftp://cpan.unam.mx/pub/CPAN
751 http://www.msg.com.mx/CPAN/
752 ftp://ftp.msg.com.mx/pub/CPAN/
764 http://mirror.hiwaay.net/CPAN/
765 ftp://mirror.hiwaay.net/CPAN/
772 ftp://cpan.valueclick.com/pub/CPAN/
773 http://mirrors.gossamer-threads.com/CPAN
774 ftp://cpan.nas.nasa.gov/pub/perl/CPAN/
775 http://mirrors.kernel.org/cpan/
776 ftp://mirrors.kernel.org/pub/CPAN
777 http://cpan.digisle.net/
778 ftp://cpan.digisle.net/pub/CPAN
779 http://www.perl.com/CPAN/
780 http://download.sourceforge.net/mirrors/CPAN/
786 ftp://ftp.cs.colorado.edu/pub/perl/CPAN/
792 http://ftp.lug.udel.edu/pub/CPAN
793 ftp://ftp.lug.udel.edu/pub/CPAN
799 ftp://ftp.dc.aleron.net/pub/CPAN/
805 ftp://ftp.cise.ufl.edu/pub/mirrors/CPAN/
806 http://mirror.csit.fsu.edu/pub/CPAN/
807 ftp://mirror.csit.fsu.edu/pub/CPAN/
813 http://uiarchive.uiuc.edu/mirrors/ftp/cpan.cse.msu.edu/
814 ftp://uiarchive.uiuc.edu/mirrors/ftp/cpan.cse.msu.edu/
820 ftp://ftp.uwsg.iu.edu/pub/perl/CPAN/
821 http://cpan.netnitco.net/
822 ftp://cpan.netnitco.net/pub/mirrors/CPAN/
823 http://archive.progeny.com/CPAN/
824 ftp://archive.progeny.com/CPAN/
825 ftp://cpan.in-span.net/
826 http://csociety-ftp.ecn.purdue.edu/pub/CPAN
827 ftp://csociety-ftp.ecn.purdue.edu/pub/CPAN
834 ftp://cpan.uky.edu/pub/CPAN/
840 ftp://ftp.ccs.neu.edu/net/mirrors/ftp.funet.fi/pub/languages/perl/CPAN/
841 http://cpan.mirrors.netnumina.com/
842 ftp://mirrors.netnumina.com/cpan/
848 ftp://cpan.cse.msu.edu/
854 ftp://ftp.cpanel.net/pub/CPAN/
855 http://cpan.teleglobe.net/
856 ftp://cpan.teleglobe.net/pub/CPAN
862 ftp://ftp.exobit.org/pub/perl/CPAN
863 http://cpan.belfry.net/
864 http://cpan.thepirtgroup.com/
865 ftp://cpan.thepirtgroup.com/
866 ftp://ftp.stealth.net/pub/CPAN/
867 http://www.rge.com/pub/languages/perl/
868 ftp://ftp.rge.com/pub/languages/perl/
869 ftp://mirrors.cloud9.net/pub/mirrors/CPAN/
875 ftp://ftp.duke.edu/pub/perl/
881 ftp://ftp.loaded.net/pub/CPAN/
887 ftp://ftp.ou.edu/mirrors/CPAN/
893 ftp://ftp.orst.edu/pub/CPAN
899 http://ftp.epix.net/CPAN/
900 ftp://ftp.epix.net/pub/languages/perl/
901 http://mirrors.phenominet.com/pub/CPAN/
902 ftp://mirrors.phenominet.com/pub/CPAN/
903 http://cpan.pair.com/
904 ftp://cpan.pair.com/pub/CPAN/
905 ftp://carroll.cac.psu.edu/pub/CPAN/
911 ftp://ftp.sunsite.utk.edu/pub/CPAN/
917 http://ftp.sedl.org/pub/mirrors/CPAN/
918 ftp://mirror.telentente.com/pub/CPAN
924 ftp://mirror.xmission.com/CPAN/
930 http://mirrors.rcn.net/pub/lang/CPAN/
931 ftp://mirrors.rcn.net/pub/lang/CPAN/
932 http://perl.secsup.org/
933 ftp://perl.secsup.org/pub/perl/
934 http://mirrors.phihost.com/CPAN/
935 ftp://mirrors.phihost.com/CPAN/
936 ftp://ruff.cs.jmu.edu/pub/CPAN/
937 http://perl.Liquidation.com/CPAN/
943 http://cpan.llarian.net/
944 ftp://cpan.llarian.net/pub/CPAN/
945 http://cpan.mirrorcentral.com/
946 ftp://ftp.mirrorcentral.com/pub/CPAN/
947 ftp://ftp-mirror.internap.com/pub/CPAN/
953 http://mirror.sit.wisc.edu/pub/CPAN/
954 ftp://mirror.sit.wisc.edu/pub/CPAN/
966 http://ftp.planetmirror.com/pub/CPAN/
967 ftp://ftp.planetmirror.com/pub/CPAN/
968 ftp://mirror.aarnet.edu.au/pub/perl/CPAN/
969 ftp://cpan.topend.com.au/pub/CPAN/
975 ftp://ftp.auckland.ac.nz/pub/perl/CPAN/
987 ftp://mirrors.bannerlandia.com.ar/mirrors/CPAN/
993 ftp://cpan.pop-mg.com.br/pub/CPAN/
994 ftp://ftp.matrix.com.br/pub/perl/CPAN/
1000 ftp://ftp.psinet.cl/pub/programming/perl/CPAN/
1004 For an up-to-date listing of CPAN sites,
1005 see http://www.cpan.org/SITES or ftp://www.cpan.org/SITES .
1007 =head1 Modules: Creation, Use, and Abuse
1009 (The following section is borrowed directly from Tim Bunce's modules
1010 file, available at your nearest CPAN site.)
1012 Perl implements a class using a package, but the presence of a
1013 package doesn't imply the presence of a class. A package is just a
1014 namespace. A class is a package that provides subroutines that can be
1015 used as methods. A method is just a subroutine that expects, as its
1016 first argument, either the name of a package (for "static" methods),
1017 or a reference to something (for "virtual" methods).
1019 A module is a file that (by convention) provides a class of the same
1020 name (sans the .pm), plus an import method in that class that can be
1021 called to fetch exported symbols. This module may implement some of
1022 its methods by loading dynamic C or C++ objects, but that should be
1023 totally transparent to the user of the module. Likewise, the module
1024 might set up an AUTOLOAD function to slurp in subroutine definitions on
1025 demand, but this is also transparent. Only the F<.pm> file is required to
1026 exist. See L<perlsub>, L<perltoot>, and L<AutoLoader> for details about
1027 the AUTOLOAD mechanism.
1029 =head2 Guidelines for Module Creation
1035 Do similar modules already exist in some form?
1037 If so, please try to reuse the existing modules either in whole or
1038 by inheriting useful features into a new class. If this is not
1039 practical try to get together with the module authors to work on
1040 extending or enhancing the functionality of the existing modules.
1041 A perfect example is the plethora of packages in perl4 for dealing
1042 with command line options.
1044 If you are writing a module to expand an already existing set of
1045 modules, please coordinate with the author of the package. It
1046 helps if you follow the same naming scheme and module interaction
1047 scheme as the original author.
1051 Try to design the new module to be easy to extend and reuse.
1053 Try to C<use warnings;> (or C<use warnings qw(...);>).
1054 Remember that you can add C<no warnings qw(...);> to individual blocks
1055 of code that need less warnings.
1057 Use blessed references. Use the two argument form of bless to bless
1058 into the class name given as the first parameter of the constructor,
1063 return bless {}, $class;
1066 or even this if you'd like it to be used as either a static
1067 or a virtual method.
1071 my $class = ref($self) || $self;
1072 return bless {}, $class;
1075 Pass arrays as references so more parameters can be added later
1076 (it's also faster). Convert functions into methods where
1077 appropriate. Split large methods into smaller more flexible ones.
1078 Inherit methods from other modules if appropriate.
1080 Avoid class name tests like: C<die "Invalid" unless ref $ref eq 'FOO'>.
1081 Generally you can delete the C<eq 'FOO'> part with no harm at all.
1082 Let the objects look after themselves! Generally, avoid hard-wired
1083 class names as far as possible.
1085 Avoid C<< $r->Class::func() >> where using C<@ISA=qw(... Class ...)> and
1086 C<< $r->func() >> would work (see L<perlbot> for more details).
1088 Use autosplit so little used or newly added functions won't be a
1089 burden to programs that don't use them. Add test functions to
1090 the module after __END__ either using AutoSplit or by saying:
1092 eval join('',<main::DATA>) || die $@ unless caller();
1094 Does your module pass the 'empty subclass' test? If you say
1095 C<@SUBCLASS::ISA = qw(YOURCLASS);> your applications should be able
1096 to use SUBCLASS in exactly the same way as YOURCLASS. For example,
1097 does your application still work if you change: C<$obj = new YOURCLASS;>
1098 into: C<$obj = new SUBCLASS;> ?
1100 Avoid keeping any state information in your packages. It makes it
1101 difficult for multiple other packages to use yours. Keep state
1102 information in objects.
1106 Try to C<use strict;> (or C<use strict qw(...);>).
1107 Remember that you can add C<no strict qw(...);> to individual blocks
1108 of code that need less strictness.
1112 Follow the guidelines in the perlstyle(1) manual.
1118 Some simple style guidelines
1120 The perlstyle manual supplied with Perl has many helpful points.
1122 Coding style is a matter of personal taste. Many people evolve their
1123 style over several years as they learn what helps them write and
1124 maintain good code. Here's one set of assorted suggestions that
1125 seem to be widely used by experienced developers:
1127 Use underscores to separate words. It is generally easier to read
1128 $var_names_like_this than $VarNamesLikeThis, especially for
1129 non-native speakers of English. It's also a simple rule that works
1130 consistently with VAR_NAMES_LIKE_THIS.
1132 Package/Module names are an exception to this rule. Perl informally
1133 reserves lowercase module names for 'pragma' modules like integer
1134 and strict. Other modules normally begin with a capital letter and
1135 use mixed case with no underscores (need to be short and portable).
1137 You may find it helpful to use letter case to indicate the scope
1138 or nature of a variable. For example:
1140 $ALL_CAPS_HERE constants only (beware clashes with Perl vars)
1141 $Some_Caps_Here package-wide global/static
1142 $no_caps_here function scope my() or local() variables
1144 Function and method names seem to work best as all lowercase.
1145 e.g., C<< $obj->as_string() >>.
1147 You can use a leading underscore to indicate that a variable or
1148 function should not be used outside the package that defined it.
1152 Select what to export.
1154 Do NOT export method names!
1156 Do NOT export anything else by default without a good reason!
1158 Exports pollute the namespace of the module user. If you must
1159 export try to use @EXPORT_OK in preference to @EXPORT and avoid
1160 short or common names to reduce the risk of name clashes.
1162 Generally anything not exported is still accessible from outside the
1163 module using the ModuleName::item_name (or C<< $blessed_ref->method >>)
1164 syntax. By convention you can use a leading underscore on names to
1165 indicate informally that they are 'internal' and not for public use.
1167 (It is actually possible to get private functions by saying:
1168 C<my $subref = sub { ... }; &$subref;>. But there's no way to call that
1169 directly as a method, because a method must have a name in the symbol
1172 As a general rule, if the module is trying to be object oriented
1173 then export nothing. If it's just a collection of functions then
1174 @EXPORT_OK anything but use @EXPORT with caution.
1178 Select a name for the module.
1180 This name should be as descriptive, accurate, and complete as
1181 possible. Avoid any risk of ambiguity. Always try to use two or
1182 more whole words. Generally the name should reflect what is special
1183 about what the module does rather than how it does it. Please use
1184 nested module names to group informally or categorize a module.
1185 There should be a very good reason for a module not to have a nested name.
1186 Module names should begin with a capital letter.
1188 Having 57 modules all called Sort will not make life easy for anyone
1189 (though having 23 called Sort::Quick is only marginally better :-).
1190 Imagine someone trying to install your module alongside many others.
1191 If in any doubt ask for suggestions in comp.lang.perl.misc.
1193 If you are developing a suite of related modules/classes it's good
1194 practice to use nested classes with a common prefix as this will
1195 avoid namespace clashes. For example: Xyz::Control, Xyz::View,
1196 Xyz::Model etc. Use the modules in this list as a naming guide.
1198 If adding a new module to a set, follow the original author's
1199 standards for naming modules and the interface to methods in
1202 If developing modules for private internal or project specific use,
1203 that will never be released to the public, then you should ensure
1204 that their names will not clash with any future public module. You
1205 can do this either by using the reserved Local::* category or by
1206 using a category name that includes an underscore like Foo_Corp::*.
1208 To be portable each component of a module name should be limited to
1209 11 characters. If it might be used on MS-DOS then try to ensure each is
1210 unique in the first 8 characters. Nested modules make this easier.
1214 Have you got it right?
1216 How do you know that you've made the right decisions? Have you
1217 picked an interface design that will cause problems later? Have
1218 you picked the most appropriate name? Do you have any questions?
1220 The best way to know for sure, and pick up many helpful suggestions,
1221 is to ask someone who knows. Comp.lang.perl.misc is read by just about
1222 all the people who develop modules and it's the best place to ask.
1224 All you need to do is post a short summary of the module, its
1225 purpose and interfaces. A few lines on each of the main methods is
1226 probably enough. (If you post the whole module it might be ignored
1227 by busy people - generally the very people you want to read it!)
1229 Don't worry about posting if you can't say when the module will be
1230 ready - just say so in the message. It might be worth inviting
1231 others to help you, they may be able to complete it for you!
1235 README and other Additional Files.
1237 It's well known that software developers usually fully document the
1238 software they write. If, however, the world is in urgent need of
1239 your software and there is not enough time to write the full
1240 documentation please at least provide a README file containing:
1246 A description of the module/package/extension etc.
1250 A copyright notice - see below.
1254 Prerequisites - what else you may need to have.
1258 How to build it - possible changes to Makefile.PL etc.
1266 Recent changes in this release, especially incompatibilities
1270 Changes / enhancements you plan to make in the future.
1274 If the README file seems to be getting too large you may wish to
1275 split out some of the sections into separate files: INSTALL,
1282 Adding a Copyright Notice.
1284 How you choose to license your work is a personal decision.
1285 The general mechanism is to assert your Copyright and then make
1286 a declaration of how others may copy/use/modify your work.
1288 Perl, for example, is supplied with two types of licence: The GNU
1289 GPL and The Artistic Licence (see the files README, Copying, and
1290 Artistic). Larry has good reasons for NOT just using the GNU GPL.
1292 My personal recommendation, out of respect for Larry, Perl, and the
1293 Perl community at large is to state something simply like:
1295 Copyright (c) 1995 Your Name. All rights reserved.
1296 This program is free software; you can redistribute it and/or
1297 modify it under the same terms as Perl itself.
1299 This statement should at least appear in the README file. You may
1300 also wish to include it in a Copying file and your source files.
1301 Remember to include the other words in addition to the Copyright.
1305 Give the module a version/issue/release number.
1307 To be fully compatible with the Exporter and MakeMaker modules you
1308 should store your module's version number in a non-my package
1309 variable called $VERSION. This should be a floating point
1310 number with at least two digits after the decimal (i.e., hundredths,
1311 e.g, C<$VERSION = "0.01">). Don't use a "1.3.2" style version.
1312 See L<Exporter> for details.
1314 It may be handy to add a function or method to retrieve the number.
1315 Use the number in announcements and archive file names when
1316 releasing the module (ModuleName-1.02.tar.Z).
1317 See perldoc ExtUtils::MakeMaker.pm for details.
1321 How to release and distribute a module.
1323 It's good idea to post an announcement of the availability of your
1324 module (or the module itself if small) to the comp.lang.perl.announce
1325 Usenet newsgroup. This will at least ensure very wide once-off
1328 If possible, register the module with CPAN. You should
1329 include details of its location in your announcement.
1331 Some notes about ftp archives: Please use a long descriptive file
1332 name that includes the version number. Most incoming directories
1333 will not be readable/listable, i.e., you won't be able to see your
1334 file after uploading it. Remember to send your email notification
1335 message as soon as possible after uploading else your file may get
1336 deleted automatically. Allow time for the file to be processed
1337 and/or check the file has been processed before announcing its
1340 FTP Archives for Perl Modules:
1342 Follow the instructions and links on:
1344 http://www.cpan.org/modules/00modlist.long.html
1345 http://www.cpan.org/modules/04pause.html
1347 or upload to one of these sites:
1349 https://pause.kbx.de/pause/
1350 http://pause.perl.org/pause/
1352 and notify <modules@perl.org>.
1354 By using the WWW interface you can ask the Upload Server to mirror
1355 your modules from your ftp or WWW site into your own directory on
1358 Please remember to send me an updated entry for the Module list!
1362 Take care when changing a released module.
1364 Always strive to remain compatible with previous released versions.
1365 Otherwise try to add a mechanism to revert to the
1366 old behavior if people rely on it. Document incompatible changes.
1372 =head2 Guidelines for Converting Perl 4 Library Scripts into Modules
1378 There is no requirement to convert anything.
1380 If it ain't broke, don't fix it! Perl 4 library scripts should
1381 continue to work with no problems. You may need to make some minor
1382 changes (like escaping non-array @'s in double quoted strings) but
1383 there is no need to convert a .pl file into a Module for just that.
1387 Consider the implications.
1389 All Perl applications that make use of the script will need to
1390 be changed (slightly) if the script is converted into a module. Is
1391 it worth it unless you plan to make other changes at the same time?
1395 Make the most of the opportunity.
1397 If you are going to convert the script to a module you can use the
1398 opportunity to redesign the interface. The guidelines for module
1399 creation above include many of the issues you should consider.
1403 The pl2pm utility will get you started.
1405 This utility will read *.pl files (given as parameters) and write
1406 corresponding *.pm files. The pl2pm utilities does the following:
1412 Adds the standard Module prologue lines
1416 Converts package specifiers from ' to ::
1420 Converts die(...) to croak(...)
1424 Several other minor changes
1428 Being a mechanical process pl2pm is not bullet proof. The converted
1429 code will need careful checking, especially any package statements.
1430 Don't delete the original .pl file till the new .pm one works!
1434 =head2 Guidelines for Reusing Application Code
1440 Complete applications rarely belong in the Perl Module Library.
1444 Many applications contain some Perl code that could be reused.
1446 Help save the world! Share your code in a form that makes it easy
1451 Break-out the reusable code into one or more separate module files.
1455 Take the opportunity to reconsider and redesign the interfaces.
1459 In some cases the 'application' can then be reduced to a small
1461 fragment of code built on top of the reusable modules. In these cases
1462 the application could invoked as:
1464 % perl -e 'use Module::Name; method(@ARGV)' ...
1466 % perl -mModule::Name ... (in perl5.002 or higher)
1472 Perl does not enforce private and public parts of its modules as you may
1473 have been used to in other languages like C++, Ada, or Modula-17. Perl
1474 doesn't have an infatuation with enforced privacy. It would prefer
1475 that you stayed out of its living room because you weren't invited, not
1476 because it has a shotgun.
1478 The module and its user have a contract, part of which is common law,
1479 and part of which is "written". Part of the common law contract is
1480 that a module doesn't pollute any namespace it wasn't asked to. The
1481 written contract for the module (A.K.A. documentation) may make other
1482 provisions. But then you know when you C<use RedefineTheWorld> that
1483 you're redefining the world and willing to take the consequences.
1486 close MANIFEST or warn "$0: failed to close MANIFEST (../MANIFEST): $!";
1487 close OUT or warn "$0: failed to close OUT (perlmodlib.tmp): $!";