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4e860d0a 1# Generated by perlmodlib.PL DO NOT EDIT!
2
f102b883 3=head1 NAME
4
5perlmodlib - constructing new Perl modules and finding existing ones
6
7=head1 DESCRIPTION
8
9=head1 THE PERL MODULE LIBRARY
10
19799a22 11Many modules are included the Perl distribution. These are described
12below, and all end in F<.pm>. You may discover compiled library
13file (usually ending in F<.so>) or small pieces of modules to be
14autoloaded (ending in F<.al>); these were automatically generated
15by the installation process. You may also discover files in the
16library directory that end in either F<.pl> or F<.ph>. These are
17old libraries supplied so that old programs that use them still
18run. The F<.pl> files will all eventually be converted into standard
19modules, and the F<.ph> files made by B<h2ph> will probably end up
20as extension modules made by B<h2xs>. (Some F<.ph> values may
21already be available through the POSIX, Errno, or Fcntl modules.)
22The B<pl2pm> file in the distribution may help in your conversion,
23but it's just a mechanical process and therefore far from bulletproof.
f102b883 24
25=head2 Pragmatic Modules
26
19799a22 27They work somewhat like compiler directives (pragmata) in that they
28tend to affect the compilation of your program, and thus will usually
29work well only when used within a C<use>, or C<no>. Most of these
30are lexically scoped, so an inner BLOCK may countermand them
31by saying:
f102b883 32
33 no integer;
34 no strict 'refs';
4438c4b7 35 no warnings;
f102b883 36
37which lasts until the end of that BLOCK.
38
19799a22 39Some pragmas are lexically scoped--typically those that affect the
40C<$^H> hints variable. Others affect the current package instead,
77ca0c92 41like C<use vars> and C<use subs>, which allow you to predeclare a
19799a22 42variables or subroutines within a particular I<file> rather than
43just a block. Such declarations are effective for the entire file
44for which they were declared. You cannot rescind them with C<no
45vars> or C<no subs>.
f102b883 46
47The following pragmas are defined (and have their own documentation).
48
49=over 12
50
09bef843 51=item attributes
52
9e107c59 53Get/set subroutine or variable attributes
09bef843 54
19799a22 55=item attrs
f102b883 56
9e107c59 57Set/get attributes of a subroutine (deprecated)
19799a22 58
59=item autouse
60
9e107c59 61Postpone load of modules until a function is used
19799a22 62
63=item base
64
65Establish IS-A relationship with base class at compile time
f102b883 66
67=item blib
68
19799a22 69Use MakeMaker's uninstalled version of a package
70
2e1d04bc 71=item bytes
9e107c59 72
2e1d04bc 73Force byte semantics rather than character semantics
9e107c59 74
75=item charnames
76
77Define character names for C<\N{named}> string literal escape.
78
19799a22 79=item constant
80
9e107c59 81Declare constants
f102b883 82
83=item diagnostics
84
2e1d04bc 85Perl compiler pragma to force verbose warning diagnostics
19799a22 86
87=item fields
88
2e1d04bc 89Compile-time class fields
19799a22 90
91=item filetest
92
2e1d04bc 93Control the filetest permission operators
f102b883 94
95=item integer
96
4e860d0a 97Use integer arithmetic instead of floating point
f102b883 98
99=item less
100
2e1d04bc 101Request less of something from the compiler
f102b883 102
f102b883 103=item locale
104
2e1d04bc 105Use and avoid POSIX locales for built-in operations
106
107=item open
108
109Set default disciplines for input and output
f102b883 110
111=item ops
112
9e107c59 113Restrict unsafe operations when compiling
f102b883 114
115=item overload
116
2e1d04bc 117Package for overloading perl operations
f102b883 118
b3eb6a9b 119=item re
120
2e1d04bc 121Alter regular expression behaviour
b3eb6a9b 122
f102b883 123=item sigtrap
124
9e107c59 125Enable simple signal handling
f102b883 126
127=item strict
128
9e107c59 129Restrict unsafe constructs
f102b883 130
131=item subs
132
2e1d04bc 133Predeclare sub names
f102b883 134
4e860d0a 135=item unicode::distinct
136
137Strictly distinguish UTF8 data and non-UTF data.
138
19799a22 139=item utf8
f102b883 140
1fa7ca25 141Enable/disable UTF-8 (or UTF-EBCDIC) in source code
f102b883 142
143=item vars
144
2e1d04bc 145Predeclare global variable names (obsolete)
f102b883 146
4438c4b7 147=item warnings
0453d815 148
9e107c59 149Control optional warnings
19799a22 150
13a2d996 151=item warnings::register
152
153Warnings import function
154
f102b883 155=back
156
157=head2 Standard Modules
158
159Standard, bundled modules are all expected to behave in a well-defined
160manner with respect to namespace pollution because they use the
161Exporter module. See their own documentation for details.
162
163=over 12
164
165=item AnyDBM_File
166
2e1d04bc 167Provide framework for multiple DBMs
f102b883 168
169=item AutoLoader
170
9e107c59 171Load subroutines only on demand
f102b883 172
173=item AutoSplit
174
9e107c59 175Split a package for autoloading
f102b883 176
19799a22 177=item B
178
2e1d04bc 179The Perl Compiler
19799a22 180
181=item B::Asmdata
182
183Autogenerated data about Perl ops, used to generate bytecode
184
185=item B::Assembler
186
187Assemble Perl bytecode
188
189=item B::Bblock
190
191Walk basic blocks
192
193=item B::Bytecode
194
195Perl compiler's bytecode backend
196
197=item B::C
198
199Perl compiler's C backend
200
201=item B::CC
202
203Perl compiler's optimized C translation backend
204
4e860d0a 205=item B::Concise
206
207Walk Perl syntax tree, printing concise info about ops
208
19799a22 209=item B::Debug
210
211Walk Perl syntax tree, printing debug info about ops
212
213=item B::Deparse
214
2e1d04bc 215Perl compiler backend to produce perl code
19799a22 216
217=item B::Disassembler
218
219Disassemble Perl bytecode
220
221=item B::Lint
222
2e1d04bc 223Perl lint
19799a22 224
225=item B::Showlex
226
227Show lexical variables used in functions or files
228
229=item B::Stackobj
230
231Helper module for CC backend
232
13a2d996 233=item B::Stash
234
235Show what stashes are loaded
236
19799a22 237=item B::Terse
238
239Walk Perl syntax tree, printing terse info about ops
240
241=item B::Xref
242
243Generates cross reference reports for Perl programs
244
f102b883 245=item Benchmark
246
2e1d04bc 247Benchmark running times of Perl code
9e107c59 248
249=item ByteLoader
250
2e1d04bc 251Load byte compiled perl code
f102b883 252
19799a22 253=item CGI
254
2e1d04bc 255Simple Common Gateway Interface Class
19799a22 256
257=item CGI::Apache
258
2e1d04bc 259Backward compatibility module for CGI.pm
19799a22 260
261=item CGI::Carp
262
263CGI routines for writing to the HTTPD (or other) error log
264
265=item CGI::Cookie
266
267Interface to Netscape Cookies
268
269=item CGI::Fast
270
271CGI Interface for Fast CGI
272
9e107c59 273=item CGI::Pretty
274
275Module to produce nicely formatted HTML code
276
19799a22 277=item CGI::Push
278
279Simple Interface to Server Push
280
281=item CGI::Switch
282
2e1d04bc 283Backward compatibility module for defunct CGI::Switch
19799a22 284
4e860d0a 285=item CGI::Util
286
287Internal utilities used by CGI module
288
f102b883 289=item CPAN
290
2e1d04bc 291Query, download and build perl modules from CPAN sites
f102b883 292
293=item CPAN::FirstTime
294
2e1d04bc 295Utility for CPAN::Config file Initialization
f102b883 296
297=item CPAN::Nox
298
19799a22 299Wrapper around CPAN.pm without using any XS module
f102b883 300
301=item Carp
302
2e1d04bc 303Warn of errors (from perspective of caller)
9e107c59 304
4e860d0a 305=item Carp::Heavy
306
307No user serviceable parts inside
308
309=item Class::ISA
310
311Report the search path for a class's ISA tree
312
f102b883 313=item Class::Struct
314
9e107c59 315Declare struct-like datatypes as Perl classes
f102b883 316
f102b883 317=item Cwd
318
9e107c59 319Get pathname of current working directory
f102b883 320
19799a22 321=item DB
322
2e1d04bc 323Programmatic interface to the Perl debugging API (draft, subject to
19799a22 324
f102b883 325=item DB_File
326
19799a22 327Perl5 access to Berkeley DB version 1.x
328
f102b883 329=item Devel::SelfStubber
330
9e107c59 331Generate stubs for a SelfLoading module
f102b883 332
4e860d0a 333=item Digest
334
335Modules that calculate message digests
336
f102b883 337=item DirHandle
338
9e107c59 339Supply object methods for directory handles
f102b883 340
19799a22 341=item Dumpvalue
342
2e1d04bc 343Provides screen dump of Perl data.
f102b883 344
13a2d996 345=item Encode
346
347Character encodings
348
4e860d0a 349=item Encode::EncodeFormat
350
351The format of encoding tables of the Encode extension
352
353=item Encode::Tcl
354
355Tcl encodings
356
f102b883 357=item English
358
2e1d04bc 359Use nice English (or awk) names for ugly punctuation variables
f102b883 360
361=item Env
362
2e1d04bc 363Perl module that imports environment variables as scalars or arrays
f102b883 364
365=item Exporter
366
2e1d04bc 367Implements default import method for modules
9e107c59 368
369=item Exporter::Heavy
370
371Exporter guts
19799a22 372
373=item ExtUtils::Command
374
2e1d04bc 375Utilities to replace common UNIX commands in Makefiles etc.
f102b883 376
422a9aca 377=item ExtUtils::Constant
378
379Generate XS code to import C header constants
380
f102b883 381=item ExtUtils::Embed
382
2e1d04bc 383Utilities for embedding Perl in C/C++ applications
f102b883 384
385=item ExtUtils::Install
386
9e107c59 387Install files from here to there
f102b883 388
19799a22 389=item ExtUtils::Installed
390
391Inventory management of installed modules
392
f102b883 393=item ExtUtils::Liblist
394
9e107c59 395Determine libraries to use and how to use them
396
397=item ExtUtils::MM_Cygwin
398
2e1d04bc 399Methods to override UN*X behaviour in ExtUtils::MakeMaker
f102b883 400
401=item ExtUtils::MM_OS2
402
2e1d04bc 403Methods to override UN*X behaviour in ExtUtils::MakeMaker
f102b883 404
405=item ExtUtils::MM_Unix
406
9e107c59 407Methods used by ExtUtils::MakeMaker
f102b883 408
409=item ExtUtils::MM_VMS
410
2e1d04bc 411Methods to override UN*X behaviour in ExtUtils::MakeMaker
19799a22 412
413=item ExtUtils::MM_Win32
414
2e1d04bc 415Methods to override UN*X behaviour in ExtUtils::MakeMaker
f102b883 416
417=item ExtUtils::MakeMaker
418
9e107c59 419Create an extension Makefile
f102b883 420
421=item ExtUtils::Manifest
422
9e107c59 423Utilities to write and check a MANIFEST file
f102b883 424
425=item ExtUtils::Mkbootstrap
426
9e107c59 427Make a bootstrap file for use by DynaLoader
f102b883 428
429=item ExtUtils::Mksymlists
430
9e107c59 431Write linker options files for dynamic extension
f102b883 432
19799a22 433=item ExtUtils::Packlist
434
9e107c59 435Manage .packlist files
19799a22 436
f102b883 437=item ExtUtils::testlib
438
9e107c59 439Add blib/* directories to @INC
f102b883 440
b6c543e3 441=item Fatal
442
9e107c59 443Replace functions with equivalents which succeed or die
b6c543e3 444
f102b883 445=item Fcntl
446
2e1d04bc 447Load the C Fcntl.h defines
f102b883 448
449=item File::Basename
450
9e107c59 451Split a pathname into pieces
452
453=item File::CheckTree
454
455Run many filetest checks on a tree
f102b883 456
f102b883 457=item File::Compare
458
19799a22 459Compare files or filehandles
f102b883 460
461=item File::Copy
462
19799a22 463Copy files or filehandles
464
465=item File::DosGlob
466
2e1d04bc 467DOS like globbing and then some
f102b883 468
469=item File::Find
470
2e1d04bc 471Traverse a file tree
f102b883 472
473=item File::Path
474
2e1d04bc 475Create or remove directory trees
f102b883 476
f505c983 477=item File::Spec
478
9e107c59 479Portably perform operations on file names
f505c983 480
165c0277 481=item File::Spec::Epoc
482
483Methods for Epoc file specs
484
f505c983 485=item File::Spec::Functions
486
9e107c59 487Portably perform operations on file names
19799a22 488
489=item File::Spec::Mac
490
491File::Spec for MacOS
492
493=item File::Spec::OS2
494
9e107c59 495Methods for OS/2 file specs
19799a22 496
497=item File::Spec::Unix
498
9e107c59 499Methods used by File::Spec
19799a22 500
501=item File::Spec::VMS
502
9e107c59 503Methods for VMS file specs
19799a22 504
505=item File::Spec::Win32
506
9e107c59 507Methods for Win32 file specs
f505c983 508
2e1d04bc 509=item File::Temp
510
511Return name and handle of a temporary file safely
512
f102b883 513=item File::stat
514
9e107c59 515By-name interface to Perl's built-in stat() functions
f102b883 516
517=item FileCache
518
9e107c59 519Keep more files open than the system permits
f102b883 520
521=item FileHandle
522
9e107c59 523Supply object methods for filehandles
f102b883 524
165c0277 525=item Filter::Simple
526
527Simplified source filtering
528
f102b883 529=item FindBin
530
2e1d04bc 531Locate directory of original perl script
f102b883 532
533=item Getopt::Long
534
9e107c59 535Extended processing of command line options
f102b883 536
537=item Getopt::Std
538
19799a22 539Process single-character switches with switch clustering
f102b883 540
541=item I18N::Collate
542
2e1d04bc 543Compare 8-bit scalar data according to the current locale
f102b883 544
422a9aca 545=item I18N::LangTags
546
547Functions for dealing with RFC3066-style language tags
548
549=item I18N::LangTags::List
550
551List of tags for human languages
552
f102b883 553=item IO
554
2e1d04bc 555Load various IO modules
f102b883 556
557=item IPC::Open2
558
9e107c59 559Open a process for both reading and writing
f102b883 560
561=item IPC::Open3
562
9e107c59 563Open a process for reading, writing, and error handling
f102b883 564
4e860d0a 565=item Locale::Constants
566
567Constants for Locale codes
568
569=item Locale::Country
570
571ISO codes for country identification (ISO 3166)
572
573=item Locale::Currency
574
575ISO three letter codes for currency identification (ISO 4217)
576
577=item Locale::Language
578
579ISO two letter codes for language identification (ISO 639)
580
422a9aca 581=item Locale::Maketext
582
583Framework for localization
584
585=item Locale::Maketext::TPJ13
586
587Article about software localization
588
f102b883 589=item Math::BigFloat
590
19799a22 591Arbitrary length float math package
f102b883 592
593=item Math::BigInt
594
19799a22 595Arbitrary size integer math package
f102b883 596
597=item Math::Complex
598
9e107c59 599Complex numbers and associated mathematical functions
f102b883 600
404b15a1 601=item Math::Trig
602
9e107c59 603Trigonometric functions
f102b883 604
2e1d04bc 605=item NDBM_File
606
607Tied access to ndbm files
608
1fa7ca25 609=item NEXT
610
611Provide a pseudo-class NEXT that allows method redispatch
612
f102b883 613=item Net::Ping
614
9e107c59 615Check a remote host for reachability
f102b883 616
617=item Net::hostent
618
9e107c59 619By-name interface to Perl's built-in gethost*() functions
f102b883 620
621=item Net::netent
622
9e107c59 623By-name interface to Perl's built-in getnet*() functions
f102b883 624
625=item Net::protoent
626
9e107c59 627By-name interface to Perl's built-in getproto*() functions
f102b883 628
629=item Net::servent
630
9e107c59 631By-name interface to Perl's built-in getserv*() functions
f102b883 632
19799a22 633=item O
f102b883 634
19799a22 635Generic interface to Perl Compiler backends
f102b883 636
2e1d04bc 637=item ODBM_File
f102b883 638
2e1d04bc 639Tied access to odbm files
f102b883 640
2e1d04bc 641=item Opcode
f102b883 642
2e1d04bc 643Disable named opcodes when compiling perl code
19799a22 644
4e860d0a 645=item POSIX
646
647Perl interface to IEEE Std 1003.1
648
649=item PerlIO
650
651On demand loader for PerlIO layers and root of PerlIO::* name space
652
9e107c59 653=item Pod::Checker
654
655Check pod documents for syntax errors
656
2e1d04bc 657=item Pod::Find
658
659Find POD documents in directory trees
660
19799a22 661=item Pod::Html
662
9e107c59 663Module to convert pod files to HTML
664
665=item Pod::InputObjects
666
2e1d04bc 667Objects representing POD input paragraphs, commands, etc.
9e107c59 668
13a2d996 669=item Pod::LaTeX
670
671Convert Pod data to formatted Latex
672
9e107c59 673=item Pod::Man
674
675Convert POD data to formatted *roff input
676
2e1d04bc 677=item Pod::ParseUtils
678
679Helpers for POD parsing and conversion
680
9e107c59 681=item Pod::Parser
682
683Base class for creating POD filters and translators
684
2e1d04bc 685=item Pod::Plainer
686
687Perl extension for converting Pod to old style Pod.
688
9e107c59 689=item Pod::Select
690
691Extract selected sections of POD from input
19799a22 692
693=item Pod::Text
694
9e107c59 695Convert POD data to formatted ASCII text
696
697=item Pod::Text::Color
698
699Convert POD data to formatted color ASCII text
700
4e860d0a 701=item Pod::Text::Overstrike
702
703Convert POD data to formatted overstrike text
704
2e1d04bc 705=item Pod::Text::Termcap
706
707Convert POD data to ASCII text with format escapes
708
9e107c59 709=item Pod::Usage
710
711Print a usage message from embedded pod documentation
f102b883 712
713=item SDBM_File
714
19799a22 715Tied access to sdbm files
f102b883 716
717=item Safe
718
19799a22 719Compile and execute code in restricted compartments
f102b883 720
721=item Search::Dict
722
9e107c59 723Search for key in dictionary file
f102b883 724
725=item SelectSaver
726
9e107c59 727Save and restore selected file handle
f102b883 728
729=item SelfLoader
730
9e107c59 731Load functions only on demand
f102b883 732
733=item Shell
734
2e1d04bc 735Run shell commands transparently within perl
f102b883 736
737=item Socket
738
2e1d04bc 739Load the C socket.h defines and structure manipulators
f102b883 740
13a2d996 741=item Storable
742
743Persistency for perl data structures
744
4e860d0a 745=item Switch
746
747A switch statement for Perl
748
f102b883 749=item Symbol
750
9e107c59 751Manipulate Perl symbols and their names
f102b883 752
2e1d04bc 753=item Term::ANSIColor
f102b883 754
2e1d04bc 755Color screen output using ANSI escape sequences
f102b883 756
757=item Term::Cap
758
2e1d04bc 759Perl termcap interface
f102b883 760
761=item Term::Complete
762
2e1d04bc 763Perl word completion module
f102b883 764
765=item Term::ReadLine
766
2e1d04bc 767Perl interface to various C<readline> packages. If
19799a22 768
769=item Test
770
9e107c59 771Provides a simple framework for writing test scripts
f102b883 772
773=item Test::Harness
774
2e1d04bc 775Run perl standard test scripts with statistics
f102b883 776
777=item Text::Abbrev
778
9e107c59 779Create an abbreviation table from a list
f102b883 780
4e860d0a 781=item Text::Balanced
782
783Extract delimited text sequences from strings.
784
f102b883 785=item Text::ParseWords
786
2e1d04bc 787Parse text into an array of tokens or array of arrays
f102b883 788
789=item Text::Soundex
790
2e1d04bc 791Implementation of the Soundex Algorithm as Described by Knuth
f102b883 792
4e860d0a 793=item Text::Tabs
794
795Expand and unexpand tabs per the unix expand(1) and unexpand(1)
796
f102b883 797=item Text::Wrap
798
9e107c59 799Line wrapping to form simple paragraphs
19799a22 800
801=item Tie::Array
802
9e107c59 803Base class for tied arrays
19799a22 804
805=item Tie::Handle
806
9e107c59 807Base class definitions for tied handles
19799a22 808
9e107c59 809=item Tie::Hash
f102b883 810
9e107c59 811Base class definitions for tied hashes
f102b883 812
813=item Tie::RefHash
814
9e107c59 815Use references as hash keys
f102b883 816
9e107c59 817=item Tie::Scalar
f102b883 818
9e107c59 819Base class definitions for tied scalars
f102b883 820
821=item Tie::SubstrHash
822
19799a22 823Fixed-table-size, fixed-key-length hashing
f102b883 824
825=item Time::Local
826
9e107c59 827Efficiently compute time from local and GMT time
f102b883 828
829=item Time::gmtime
830
9e107c59 831By-name interface to Perl's built-in gmtime() function
f102b883 832
833=item Time::localtime
834
9e107c59 835By-name interface to Perl's built-in localtime() function
f102b883 836
837=item Time::tm
838
9e107c59 839Internal object used by Time::gmtime and Time::localtime
f102b883 840
841=item UNIVERSAL
842
9e107c59 843Base class for ALL classes (blessed references)
f102b883 844
845=item User::grent
846
9e107c59 847By-name interface to Perl's built-in getgr*() functions
f102b883 848
849=item User::pwent
850
9e107c59 851By-name interface to Perl's built-in getpw*() functions
f102b883 852
4e860d0a 853=item Win32
854
855Interfaces to some Win32 API Functions
856
f102b883 857=back
858
19799a22 859To find out I<all> modules installed on your system, including
2e1d04bc 860those without documentation or outside the standard release,
b1866b2d 861just do this:
f102b883 862
5a964f20 863 % find `perl -e 'print "@INC"'` -name '*.pm' -print
f102b883 864
2e1d04bc 865They should all have their own documentation installed and accessible
866via your system man(1) command. If you do not have a B<find>
19799a22 867program, you can use the Perl B<find2perl> program instead, which
868generates Perl code as output you can run through perl. If you
869have a B<man> program but it doesn't find your modules, you'll have
2e1d04bc 870to fix your manpath. See L<perl> for details. If you have no
871system B<man> command, you might try the B<perldoc> program.
f102b883 872
873=head2 Extension Modules
874
19799a22 875Extension modules are written in C (or a mix of Perl and C). They
876are usually dynamically loaded into Perl if and when you need them,
2e1d04bc 877but may also be be linked in statically. Supported extension modules
19799a22 878include Socket, Fcntl, and POSIX.
f102b883 879
880Many popular C extension modules do not come bundled (at least, not
19799a22 881completely) due to their sizes, volatility, or simply lack of time
882for adequate testing and configuration across the multitude of
883platforms on which Perl was beta-tested. You are encouraged to
884look for them on CPAN (described below), or using web search engines
885like Alta Vista or Deja News.
f102b883 886
887=head1 CPAN
888
19799a22 889CPAN stands for Comprehensive Perl Archive Network; it's a globally
890replicated trove of Perl materials, including documentation, style
2e1d04bc 891guides, tricks and traps, alternate ports to non-Unix systems and
19799a22 892occasional binary distributions for these. Search engines for
893CPAN can be found at http://cpan.perl.com/ and at
894http://theory.uwinnipeg.ca/mod_perl/cpan-search.pl .
895
896Most importantly, CPAN includes around a thousand unbundled modules,
897some of which require a C compiler to build. Major categories of
898modules are:
f102b883 899
4e860d0a 900=over
f102b883 901
902=item *
551e1d92 903
f102b883 904Language Extensions and Documentation Tools
905
906=item *
551e1d92 907
f102b883 908Development Support
909
910=item *
551e1d92 911
f102b883 912Operating System Interfaces
913
914=item *
551e1d92 915
f102b883 916Networking, Device Control (modems) and InterProcess Communication
917
918=item *
551e1d92 919
f102b883 920Data Types and Data Type Utilities
921
922=item *
551e1d92 923
f102b883 924Database Interfaces
925
926=item *
551e1d92 927
f102b883 928User Interfaces
929
930=item *
551e1d92 931
f102b883 932Interfaces to / Emulations of Other Programming Languages
933
934=item *
551e1d92 935
f102b883 936File Names, File Systems and File Locking (see also File Handles)
937
938=item *
551e1d92 939
f102b883 940String Processing, Language Text Processing, Parsing, and Searching
941
942=item *
551e1d92 943
f102b883 944Option, Argument, Parameter, and Configuration File Processing
945
946=item *
551e1d92 947
f102b883 948Internationalization and Locale
949
950=item *
551e1d92 951
f102b883 952Authentication, Security, and Encryption
953
954=item *
551e1d92 955
f102b883 956World Wide Web, HTML, HTTP, CGI, MIME
957
958=item *
551e1d92 959
f102b883 960Server and Daemon Utilities
961
962=item *
551e1d92 963
f102b883 964Archiving and Compression
965
966=item *
551e1d92 967
f102b883 968Images, Pixmap and Bitmap Manipulation, Drawing, and Graphing
969
970=item *
551e1d92 971
f102b883 972Mail and Usenet News
973
974=item *
551e1d92 975
f102b883 976Control Flow Utilities (callbacks and exceptions etc)
977
978=item *
551e1d92 979
f102b883 980File Handle and Input/Output Stream Utilities
981
982=item *
551e1d92 983
f102b883 984Miscellaneous Modules
985
986=back
987
19799a22 988Registered CPAN sites as of this writing include the following.
f102b883 989You should try to choose one close to you:
990
4e860d0a 991=head2 Africa
992
cea6626f 993=over 4
f102b883 994
4e860d0a 995=item *
996
997South Africa
998
999 ftp://ftp.is.co.za/programming/perl/CPAN/
1000 ftp://ftp.saix.net/pub/CPAN/
1001 ftp://ftpza.co.za/pub/mirrors/cpan/
1002 ftp://ftp.sun.ac.za/CPAN/
1003
1004=back
1005
1006=head2 Asia
1007
1008=over 4
1009
1010=item *
1011
1012China
1013
1014 ftp://freesoft.cei.gov.cn/pub/languages/perl/CPAN/
1015 http://www2.linuxforum.net/mirror/CPAN/
1016 http://cpan.shellhung.org/
1017 ftp://ftp.shellhung.org/pub/CPAN
1018
1019=item *
1020
1021Hong Kong
1022
1023 http://CPAN.pacific.net.hk/
1024 ftp://ftp.pacific.net.hk/pub/mirror/CPAN/
1025
1026=item *
1027
1028Indonesia
1029
1030 http://piksi.itb.ac.id/CPAN/
1031 ftp://mirrors.piksi.itb.ac.id/CPAN/
1032 http://CPAN.mweb.co.id/
1033 ftp://ftp.mweb.co.id/pub/languages/perl/CPAN/
1034
1035=item *
1036
1037Israel
1038
1039 http://www.iglu.org.il:/pub/CPAN/
1040 ftp://ftp.iglu.org.il/pub/CPAN/
1041 http://bioinfo.weizmann.ac.il/pub/software/perl/CPAN/
1042 ftp://bioinfo.weizmann.ac.il/pub/software/perl/CPAN/
1043
1044=item *
1045
1046Japan
1047
1048 ftp://ftp.u-aizu.ac.jp/pub/lang/perl/CPAN/
1049 ftp://ftp.kddlabs.co.jp/CPAN/
1050 http://mirror.nucba.ac.jp/mirror/Perl/
1051 ftp://mirror.nucba.ac.jp/mirror/Perl/
1052 ftp://ftp.meisei-u.ac.jp/pub/CPAN/
1053 ftp://ftp.jaist.ac.jp/pub/lang/perl/CPAN/
1054 ftp://ftp.dti.ad.jp/pub/lang/CPAN/
1055 ftp://ftp.ring.gr.jp/pub/lang/perl/CPAN/
1056
1057=item *
1058
1059Saudi Arabia
1060
1061 ftp://ftp.isu.net.sa/pub/CPAN/
1062
1063=item *
1064
1065Singapore
1066
1067 http://cpan.hjc.edu.sg
1068 http://ftp.nus.edu.sg/unix/perl/CPAN/
1069 ftp://ftp.nus.edu.sg/pub/unix/perl/CPAN/
1070
1071=item *
1072
1073South Korea
1074
1075 http://CPAN.bora.net/
1076 ftp://ftp.bora.net/pub/CPAN/
1077 http://ftp.kornet.net/CPAN/
1078 ftp://ftp.kornet.net/pub/CPAN/
1079 ftp://ftp.nuri.net/pub/CPAN/
1080
1081=item *
1082
1083Taiwan
1084
1085 ftp://coda.nctu.edu.tw/UNIX/perl/CPAN
1086 ftp://ftp.ee.ncku.edu.tw/pub/perl/CPAN/
1087 ftp://ftp1.sinica.edu.tw/pub1/perl/CPAN/
1088
1089=item *
1090
1091Thailand
1092
1093 http://download.nectec.or.th/CPAN/
1094 ftp://ftp.nectec.or.th/pub/languages/CPAN/
1095 ftp://ftp.cs.riubon.ac.th/pub/mirrors/CPAN/
1096
1097=back
1098
1099=head2 Central America
1100
1101=over 4
1102
1103=item *
1104
1105Costa Rica
1106
1107 ftp://ftp.linux.co.cr/mirrors/CPAN/
1108 http://ftp.ucr.ac.cr/Unix/CPAN/
1109 ftp://ftp.ucr.ac.cr/pub/Unix/CPAN/
1110
1111=back
1112
1113=head2 Europe
1114
1115=over 4
1116
1117=item *
1118
1119Austria
1120
1121 ftp://ftp.tuwien.ac.at/pub/languages/perl/CPAN/
1122
1123=item *
1124
1125Belgium
1126
1127 http://ftp.easynet.be/CPAN/
1128 ftp://ftp.easynet.be/CPAN/
1129 ftp://ftp.kulnet.kuleuven.ac.be/pub/mirror/CPAN/
1130
1131=item *
1132
1133Bulgaria
1134
1135 ftp://ftp.ntrl.net/pub/mirrors/CPAN/
1136
1137=item *
1138
1139Croatia
1140
1141 ftp://ftp.linux.hr/pub/CPAN/
1142
1143=item *
1144
1145Czech Republic
1146
1147 http://www.fi.muni.cz/pub/perl/
1148 ftp://ftp.fi.muni.cz/pub/perl/
1149 ftp://sunsite.mff.cuni.cz/MIRRORS/ftp.funet.fi/pub/languages/perl/CPAN/
1150
1151=item *
1152
1153Denmark
1154
1155 ftp://sunsite.auc.dk/pub/languages/perl/CPAN/
1156 http://www.cpan.dk/CPAN/
1157 ftp://www.cpan.dk/ftp.cpan.org/CPAN/
1158
1159=item *
1160
1161England
1162
1163 http://www.mirror.ac.uk/sites/ftp.funet.fi/pub/languages/perl/CPAN
1164 ftp://ftp.mirror.ac.uk/sites/ftp.funet.fi/pub/languages/perl/CPAN/
1165 ftp://ftp.demon.co.uk/pub/mirrors/perl/CPAN/
1166 ftp://ftp.flirble.org/pub/languages/perl/CPAN/
1167 ftp://ftp.plig.org/pub/CPAN/
1168 ftp://sunsite.doc.ic.ac.uk/packages/CPAN/
1169 http://mirror.uklinux.net/CPAN/
1170 ftp://mirror.uklinux.net/pub/CPAN/
1171 ftp://usit.shef.ac.uk/pub/packages/CPAN/
1172
1173=item *
1174
1175Estonia
1176
1177 ftp://ftp.ut.ee/pub/languages/perl/CPAN/
1178
1179=item *
1180
1181Finland
1182
1183 ftp://ftp.funet.fi/pub/languages/perl/CPAN/
1184
1185=item *
1186
1187France
1188
1189 ftp://cpan.ftp.worldonline.fr/pub/CPAN/
1190 ftp://ftp.club-internet.fr/pub/perl/CPAN/
1191 ftp://ftp.lip6.fr/pub/perl/CPAN/
1192 ftp://ftp.oleane.net/pub/mirrors/CPAN/
1193 ftp://ftp.pasteur.fr/pub/computing/CPAN/
1194 ftp://cpan.cict.fr/pub/CPAN/
1195 ftp://ftp.uvsq.fr/pub/perl/CPAN/
1196
1197=item *
1198
1199Germany
1200
1201 ftp://ftp.rz.ruhr-uni-bochum.de/pub/CPAN/
1202 ftp://ftp.freenet.de/pub/ftp.cpan.org/pub/CPAN/
1203 ftp://ftp.uni-erlangen.de/pub/source/CPAN/
1204 ftp://ftp-stud.fht-esslingen.de/pub/Mirrors/CPAN
1205 ftp://ftp.gigabell.net/pub/CPAN/
1206 http://ftp.gwdg.de/pub/languages/perl/CPAN/
1207 ftp://ftp.gwdg.de/pub/languages/perl/CPAN/
1208 ftp://ftp.uni-hamburg.de/pub/soft/lang/perl/CPAN/
1209 ftp://ftp.leo.org/pub/comp/general/programming/languages/script/perl/CPAN/
1210 ftp://ftp.mpi-sb.mpg.de/pub/perl/CPAN/
1211 ftp://ftp.gmd.de/mirrors/CPAN/
1212
1213=item *
1214
1215Greece
1216
1217 ftp://ftp.forthnet.gr/pub/languages/perl/CPAN
1218 ftp://ftp.ntua.gr/pub/lang/perl/
1219
1220=item *
1221
1222Hungary
1223
1224 http://cpan.artifact.hu/
1225 ftp://cpan.artifact.hu/CPAN/
1226 ftp://ftp.kfki.hu/pub/packages/perl/CPAN/
1227
1228=item *
1229
1230Iceland
1231
1232 http://cpan.gm.is/
1233 ftp://ftp.gm.is/pub/CPAN/
1234
1235=item *
1236
1237Ireland
1238
1239 http://cpan.indigo.ie/
1240 ftp://cpan.indigo.ie/pub/CPAN/
1241 http://sunsite.compapp.dcu.ie/pub/perl/
1242 ftp://sunsite.compapp.dcu.ie/pub/perl/
1243
1244=item *
1245
1246Italy
1247
1248 http://cpan.nettuno.it/
1249 http://gusp.dyndns.org/CPAN/
1250 ftp://gusp.dyndns.org/pub/CPAN
1251 http://softcity.iol.it/cpan
1252 ftp://softcity.iol.it/pub/cpan
1253 ftp://ftp.unina.it/pub/Other/CPAN/
1254 ftp://ftp.unipi.it/pub/mirror/perl/CPAN/
1255 ftp://cis.uniRoma2.it/CPAN/
1256 ftp://ftp.edisontel.it/pub/CPAN_Mirror/
1257 ftp://ftp.flashnet.it/pub/CPAN/
1258
1259=item *
1260
1261Latvia
1262
1263 http://kvin.lv/pub/CPAN/
1264
1265=item *
1266
1267Netherlands
1268
1269 ftp://download.xs4all.nl/pub/mirror/CPAN/
1270 ftp://ftp.nl.uu.net/pub/CPAN/
1271 ftp://ftp.nluug.nl/pub/languages/perl/CPAN/
1272 ftp://ftp.cpan.nl/pub/CPAN/
1273 http://www.cs.uu.nl/mirror/CPAN/
1274 ftp://ftp.cs.uu.nl/mirror/CPAN/
1275
1276=item *
1277
1278Norway
1279
1280 ftp://sunsite.uio.no/pub/languages/perl/CPAN/
1281 ftp://ftp.uit.no/pub/languages/perl/cpan/
1282
1283=item *
1284
1285Poland
1286
1287 ftp://ftp.pk.edu.pl/pub/lang/perl/CPAN/
1288 ftp://ftp.mega.net.pl/pub/mirrors/ftp.perl.com/
1289 ftp://ftp.man.torun.pl/pub/doc/CPAN/
1290 ftp://sunsite.icm.edu.pl/pub/CPAN/
1291
1292=item *
1293
1294Portugal
1295
1296 ftp://ftp.ua.pt/pub/CPAN/
1297 ftp://perl.di.uminho.pt/pub/CPAN/
1298 ftp://ftp.ist.utl.pt/pub/CPAN/
1299 ftp://ftp.netc.pt/pub/CPAN/
1300
1301=item *
1302
1303Romania
1304
1305 ftp://archive.logicnet.ro/mirrors/ftp.cpan.org/CPAN/
1306 ftp://ftp.kappa.ro/pub/mirrors/ftp.perl.org/pub/CPAN/
1307 ftp://ftp.dntis.ro/pub/cpan/
1308 ftp://ftp.opsynet.com/cpan/
1309 ftp://ftp.dnttm.ro/pub/CPAN/
1310 ftp://ftp.timisoara.roedu.net/mirrors/CPAN/
1311
1312=item *
1313
1314Russia
1315
1316 ftp://ftp.chg.ru/pub/lang/perl/CPAN/
1317 http://cpan.rinet.ru/
1318 ftp://cpan.rinet.ru/pub/mirror/CPAN/
1319 ftp://ftp.aha.ru/pub/CPAN/
1320 ftp://ftp.sai.msu.su/pub/lang/perl/CPAN/
1321
1322=item *
1323
1324Slovakia
1325
1326 ftp://ftp.entry.sk/pub/languages/perl/CPAN/
1327
1328=item *
1329
1330Slovenia
1331
1332 ftp://ftp.arnes.si/software/perl/CPAN/
1333
1334=item *
1335
1336Spain
1337
1338 ftp://ftp.rediris.es/mirror/CPAN/
1339 ftp://ftp.etse.urv.es/pub/perl/
1340
1341=item *
1342
1343Sweden
1344
1345 http://ftp.du.se/CPAN/
1346 ftp://ftp.du.se/pub/CPAN/
1347 ftp://ftp.sunet.se/pub/lang/perl/CPAN/
1348
1349=item *
1350
1351Switzerland
1352
1353 ftp://ftp.danyk.ch/CPAN/
1354 ftp://sunsite.cnlab-switch.ch/mirror/CPAN/
1355
1356=item *
1357
1358Turkey
1359
1360 ftp://sunsite.bilkent.edu.tr/pub/languages/CPAN/
1361
1362=back
1363
1364=head2 North America
1365
1366=over 4
1367
1368=item *
1369
1370Canada
1371
1372=over 8
1373
1374=item *
1375
1376Alberta
1377
1378 http://sunsite.ualberta.ca/pub/Mirror/CPAN/
1379 ftp://sunsite.ualberta.ca/pub/Mirror/CPAN/
1380
1381=item *
1382
1383Manitoba
1384
1385 http://theoryx5.uwinnipeg.ca/pub/CPAN/
1386 ftp://theoryx5.uwinnipeg.ca/pub/CPAN/
1387
1388=item *
1389
1390Nova Scotia
1391
1392 ftp://cpan.chebucto.ns.ca/pub/CPAN/
1393
1394=item *
1395
1396Ontario
1397
1398 ftp://ftp.crc.ca/pub/packages/lang/perl/CPAN/
1399
1400=item *
1401
1402Mexico
1403
1404 http://www.msg.com.mx/CPAN/
1405 ftp://ftp.msg.com.mx/pub/CPAN/
1406
1407=back
1408
1409=item *
1410
1411United States
1412
1413=over 8
1414
1415=item *
1416
1417Alabama
1418
1419 http://mirror.hiwaay.net/CPAN/
1420 ftp://mirror.hiwaay.net/CPAN/
1421
1422=item *
1423
1424California
1425
1426 http://www.cpan.org/
1427 ftp://ftp.cpan.org/CPAN/
1428 ftp://cpan.nas.nasa.gov/pub/perl/CPAN/
1429 ftp://ftp.digital.com/pub/plan/perl/CPAN/
1430 http://www.kernel.org/pub/mirrors/cpan/
1431 ftp://ftp.kernel.org/pub/mirrors/cpan/
1432 http://www.perl.com/CPAN/
1433 http://download.sourceforge.net/mirrors/CPAN/
1434
1435=item *
1436
1437Colorado
1438
1439 ftp://ftp.cs.colorado.edu/pub/perl/CPAN/
1440
1441=item *
1442
1443Florida
1444
1445 ftp://ftp.cise.ufl.edu/pub/perl/CPAN/
1446
1447=item *
1448
1449Georgia
1450
1451 ftp://ftp.twoguys.org/CPAN/
1452
1453=item *
1454
1455Illinois
1456
1457 http://www.neurogames.com/mirrors/CPAN
1458 http://uiarchive.uiuc.edu/mirrors/ftp/ftp.cpan.org/pub/CPAN/
1459 ftp://uiarchive.uiuc.edu/mirrors/ftp/ftp.cpan.org/pub/CPAN/
1460
1461=item *
1462
1463Indiana
1464
1465 ftp://ftp.uwsg.indiana.edu/pub/perl/CPAN/
1466 http://cpan.nitco.com/
1467 ftp://cpan.nitco.com/pub/CPAN/
1468 ftp://cpan.in-span.net/
1469 http://csociety-ftp.ecn.purdue.edu/pub/CPAN
1470 ftp://csociety-ftp.ecn.purdue.edu/pub/CPAN
1471
1472=item *
1473
1474Kentucky
1475
1476 http://cpan.uky.edu/
1477 ftp://cpan.uky.edu/pub/CPAN/
1478
1479=item *
1480
1481Massachusetts
1482
1483 ftp://ftp.ccs.neu.edu/net/mirrors/ftp.funet.fi/pub/languages/perl/CPAN/
1484 ftp://ftp.iguide.com/pub/mirrors/packages/perl/CPAN/
1485
1486=item *
1487
1488New Jersey
1489
1490 ftp://ftp.cpanel.net/pub/CPAN/
1491
1492=item *
1493
1494New York
1495
1496 ftp://ftp.freesoftware.com/pub/perl/CPAN/
1497 http://www.deao.net/mirrors/CPAN/
1498 ftp://ftp.deao.net/pub/CPAN/
1499 ftp://ftp.stealth.net/pub/mirrors/ftp.cpan.org/pub/CPAN/
1500 http://mirror.nyc.anidea.com/CPAN/
1501 ftp://mirror.nyc.anidea.com/pub/CPAN/
1502 http://www.rge.com/pub/languages/perl/
1503 ftp://ftp.rge.com/pub/languages/perl/
1504 ftp://mirrors.cloud9.net/pub/mirrors/CPAN/
1505
1506=item *
1507
1508North Carolina
1509
1510 ftp://ftp.duke.edu/pub/perl/
1511
1512=item *
1513
1514Ohio
1515
1516 ftp://ftp.loaded.net/pub/CPAN/
1517
1518=item *
1519
1520Oklahoma
1521
1522 ftp://ftp.ou.edu/mirrors/CPAN/
1523
1524=item *
1525
1526Oregon
1527
1528 ftp://ftp.orst.edu/pub/packages/CPAN/
1529
1530=item *
1531
1532Pennsylvania
1533
1534 http://ftp.epix.net/CPAN/
1535 ftp://ftp.epix.net/pub/languages/perl/
1536 ftp://carroll.cac.psu.edu/pub/CPAN/
1537
1538=item *
1539
1540Tennessee
1541
1542 ftp://ftp.sunsite.utk.edu/pub/CPAN/
1543
1544=item *
1545
1546Texas
1547
1548 http://ftp.sedl.org/pub/mirrors/CPAN/
1549 http://jhcloos.com/pub/mirror/CPAN/
1550 ftp://jhcloos.com/pub/mirror/CPAN/
1551
1552=item *
1553
1554Utah
1555
1556 ftp://mirror.xmission.com/CPAN/
1557
1558=item *
1559
1560Virginia
1561
1562 http://mirrors.rcn.net/pub/lang/CPAN/
1563 ftp://mirrors.rcn.net/pub/lang/CPAN/
1564 ftp://ruff.cs.jmu.edu/pub/CPAN/
1565 http://perl.Liquidation.com/CPAN/
1566
1567=item *
1568
1569Washington
1570
1571 http://cpan.llarian.net/
1572 ftp://cpan.llarian.net/pub/CPAN/
1573 ftp://ftp-mirror.internap.com/pub/CPAN/
1574 ftp://ftp.spu.edu/pub/CPAN/
1575
1576=back
1577
1578=back
1579
1580=head2 Oceania
1581
1582=over 4
1583
1584=item *
1585
1586Australia
1587
1588 http://ftp.planetmirror.com/pub/CPAN/
1589 ftp://ftp.planetmirror.com/pub/CPAN/
1590 ftp://mirror.aarnet.edu.au/pub/perl/CPAN/
1591 ftp://cpan.topend.com.au/pub/CPAN/
1592
1593=item *
1594
1595New Zealand
1596
1597 ftp://ftp.auckland.ac.nz/pub/perl/CPAN/
1598
1599=back
1600
1601=head2 South America
1602
1603=over 4
1604
1605=item *
1606
1607Argentina
1608
1609 ftp://mirrors.bannerlandia.com.ar/mirrors/CPAN/
1610
1611=item *
1612
1613Brazil
1614
1615 ftp://cpan.pop-mg.com.br/pub/CPAN/
1616 ftp://ftp.matrix.com.br/pub/perl/
1617 ftp://cpan.if.usp.br/pub/mirror/CPAN/
1618
1619=item *
1620
1621Chile
1622
1623 ftp://ftp.psinet.cl/pub/programming/perl/CPAN/
1624 ftp://sunsite.dcc.uchile.cl/pub/lang/perl/
f102b883 1625
1626=back
1627
1628For an up-to-date listing of CPAN sites,
4e860d0a 1629see http://www.cpan.org/SITES or ftp://www.cpan.org/SITES .
f102b883 1630
1631=head1 Modules: Creation, Use, and Abuse
1632
1633(The following section is borrowed directly from Tim Bunce's modules
1634file, available at your nearest CPAN site.)
1635
1636Perl implements a class using a package, but the presence of a
1637package doesn't imply the presence of a class. A package is just a
1638namespace. A class is a package that provides subroutines that can be
1639used as methods. A method is just a subroutine that expects, as its
1640first argument, either the name of a package (for "static" methods),
1641or a reference to something (for "virtual" methods).
1642
1643A module is a file that (by convention) provides a class of the same
1644name (sans the .pm), plus an import method in that class that can be
1645called to fetch exported symbols. This module may implement some of
1646its methods by loading dynamic C or C++ objects, but that should be
1647totally transparent to the user of the module. Likewise, the module
1648might set up an AUTOLOAD function to slurp in subroutine definitions on
1649demand, but this is also transparent. Only the F<.pm> file is required to
2e1d04bc 1650exist. See L<perlsub>, L<perltoot>, and L<AutoLoader> for details about
f102b883 1651the AUTOLOAD mechanism.
1652
1653=head2 Guidelines for Module Creation
1654
1655=over 4
1656
4e860d0a 1657=item *
1658
1659Do similar modules already exist in some form?
f102b883 1660
1661If so, please try to reuse the existing modules either in whole or
1662by inheriting useful features into a new class. If this is not
1663practical try to get together with the module authors to work on
1664extending or enhancing the functionality of the existing modules.
1665A perfect example is the plethora of packages in perl4 for dealing
1666with command line options.
1667
1668If you are writing a module to expand an already existing set of
1669modules, please coordinate with the author of the package. It
1670helps if you follow the same naming scheme and module interaction
1671scheme as the original author.
1672
4e860d0a 1673=item *
1674
1675Try to design the new module to be easy to extend and reuse.
f102b883 1676
9f1b1f2d 1677Try to C<use warnings;> (or C<use warnings qw(...);>).
1678Remember that you can add C<no warnings qw(...);> to individual blocks
2e1d04bc 1679of code that need less warnings.
19799a22 1680
f102b883 1681Use blessed references. Use the two argument form of bless to bless
1682into the class name given as the first parameter of the constructor,
1683e.g.,:
1684
1685 sub new {
2e1d04bc 1686 my $class = shift;
1687 return bless {}, $class;
f102b883 1688 }
1689
1690or even this if you'd like it to be used as either a static
1691or a virtual method.
1692
1693 sub new {
2e1d04bc 1694 my $self = shift;
1695 my $class = ref($self) || $self;
1696 return bless {}, $class;
f102b883 1697 }
1698
1699Pass arrays as references so more parameters can be added later
1700(it's also faster). Convert functions into methods where
1701appropriate. Split large methods into smaller more flexible ones.
1702Inherit methods from other modules if appropriate.
1703
1704Avoid class name tests like: C<die "Invalid" unless ref $ref eq 'FOO'>.
19799a22 1705Generally you can delete the C<eq 'FOO'> part with no harm at all.
f102b883 1706Let the objects look after themselves! Generally, avoid hard-wired
1707class names as far as possible.
1708
c47ff5f1 1709Avoid C<< $r->Class::func() >> where using C<@ISA=qw(... Class ...)> and
1710C<< $r->func() >> would work (see L<perlbot> for more details).
f102b883 1711
1712Use autosplit so little used or newly added functions won't be a
5a964f20 1713burden to programs that don't use them. Add test functions to
f102b883 1714the module after __END__ either using AutoSplit or by saying:
1715
1716 eval join('',<main::DATA>) || die $@ unless caller();
1717
1718Does your module pass the 'empty subclass' test? If you say
19799a22 1719C<@SUBCLASS::ISA = qw(YOURCLASS);> your applications should be able
f102b883 1720to use SUBCLASS in exactly the same way as YOURCLASS. For example,
1721does your application still work if you change: C<$obj = new YOURCLASS;>
1722into: C<$obj = new SUBCLASS;> ?
1723
1724Avoid keeping any state information in your packages. It makes it
1725difficult for multiple other packages to use yours. Keep state
1726information in objects.
1727
2e1d04bc 1728Always use B<-w>.
19799a22 1729
1730Try to C<use strict;> (or C<use strict qw(...);>).
f102b883 1731Remember that you can add C<no strict qw(...);> to individual blocks
2e1d04bc 1732of code that need less strictness.
19799a22 1733
2e1d04bc 1734Always use B<-w>.
19799a22 1735
f102b883 1736Follow the guidelines in the perlstyle(1) manual.
1737
19799a22 1738Always use B<-w>.
1739
4e860d0a 1740=item *
1741
1742Some simple style guidelines
f102b883 1743
5a964f20 1744The perlstyle manual supplied with Perl has many helpful points.
f102b883 1745
1746Coding style is a matter of personal taste. Many people evolve their
1747style over several years as they learn what helps them write and
1748maintain good code. Here's one set of assorted suggestions that
1749seem to be widely used by experienced developers:
1750
1751Use underscores to separate words. It is generally easier to read
1752$var_names_like_this than $VarNamesLikeThis, especially for
1753non-native speakers of English. It's also a simple rule that works
1754consistently with VAR_NAMES_LIKE_THIS.
1755
1756Package/Module names are an exception to this rule. Perl informally
1757reserves lowercase module names for 'pragma' modules like integer
1758and strict. Other modules normally begin with a capital letter and
1759use mixed case with no underscores (need to be short and portable).
1760
1761You may find it helpful to use letter case to indicate the scope
1762or nature of a variable. For example:
1763
5a964f20 1764 $ALL_CAPS_HERE constants only (beware clashes with Perl vars)
f102b883 1765 $Some_Caps_Here package-wide global/static
1766 $no_caps_here function scope my() or local() variables
1767
1768Function and method names seem to work best as all lowercase.
c47ff5f1 1769e.g., C<< $obj->as_string() >>.
f102b883 1770
1771You can use a leading underscore to indicate that a variable or
1772function should not be used outside the package that defined it.
1773
4e860d0a 1774=item *
1775
1776Select what to export.
f102b883 1777
1778Do NOT export method names!
1779
1780Do NOT export anything else by default without a good reason!
1781
1782Exports pollute the namespace of the module user. If you must
1783export try to use @EXPORT_OK in preference to @EXPORT and avoid
1784short or common names to reduce the risk of name clashes.
1785
1786Generally anything not exported is still accessible from outside the
c47ff5f1 1787module using the ModuleName::item_name (or C<< $blessed_ref->method >>)
f102b883 1788syntax. By convention you can use a leading underscore on names to
1789indicate informally that they are 'internal' and not for public use.
1790
1791(It is actually possible to get private functions by saying:
1792C<my $subref = sub { ... }; &$subref;>. But there's no way to call that
1793directly as a method, because a method must have a name in the symbol
1794table.)
1795
1796As a general rule, if the module is trying to be object oriented
1797then export nothing. If it's just a collection of functions then
1798@EXPORT_OK anything but use @EXPORT with caution.
1799
4e860d0a 1800=item *
1801
1802Select a name for the module.
f102b883 1803
1804This name should be as descriptive, accurate, and complete as
1805possible. Avoid any risk of ambiguity. Always try to use two or
1806more whole words. Generally the name should reflect what is special
1807about what the module does rather than how it does it. Please use
1808nested module names to group informally or categorize a module.
1809There should be a very good reason for a module not to have a nested name.
1810Module names should begin with a capital letter.
1811
1812Having 57 modules all called Sort will not make life easy for anyone
1813(though having 23 called Sort::Quick is only marginally better :-).
1814Imagine someone trying to install your module alongside many others.
1815If in any doubt ask for suggestions in comp.lang.perl.misc.
1816
1817If you are developing a suite of related modules/classes it's good
1818practice to use nested classes with a common prefix as this will
1819avoid namespace clashes. For example: Xyz::Control, Xyz::View,
1820Xyz::Model etc. Use the modules in this list as a naming guide.
1821
1822If adding a new module to a set, follow the original author's
1823standards for naming modules and the interface to methods in
1824those modules.
1825
165c0277 1826If developing modules for private internal or project specific use,
1827that will never be released to the public, then you should ensure
1828that their names will not clash with any future public module. You
1829can do this either by using the reserved Local::* category or by
1830using a category name that includes an underscore like Foo_Corp::*.
1831
f102b883 1832To be portable each component of a module name should be limited to
183311 characters. If it might be used on MS-DOS then try to ensure each is
1834unique in the first 8 characters. Nested modules make this easier.
1835
4e860d0a 1836=item *
1837
1838Have you got it right?
f102b883 1839
1840How do you know that you've made the right decisions? Have you
1841picked an interface design that will cause problems later? Have
1842you picked the most appropriate name? Do you have any questions?
1843
1844The best way to know for sure, and pick up many helpful suggestions,
1845is to ask someone who knows. Comp.lang.perl.misc is read by just about
1846all the people who develop modules and it's the best place to ask.
1847
1848All you need to do is post a short summary of the module, its
1849purpose and interfaces. A few lines on each of the main methods is
1850probably enough. (If you post the whole module it might be ignored
1851by busy people - generally the very people you want to read it!)
1852
1853Don't worry about posting if you can't say when the module will be
1854ready - just say so in the message. It might be worth inviting
1855others to help you, they may be able to complete it for you!
1856
4e860d0a 1857=item *
1858
1859README and other Additional Files.
f102b883 1860
1861It's well known that software developers usually fully document the
1862software they write. If, however, the world is in urgent need of
1863your software and there is not enough time to write the full
1864documentation please at least provide a README file containing:
1865
1866=over 10
1867
1868=item *
4e860d0a 1869
f102b883 1870A description of the module/package/extension etc.
1871
1872=item *
4e860d0a 1873
f102b883 1874A copyright notice - see below.
1875
1876=item *
4e860d0a 1877
f102b883 1878Prerequisites - what else you may need to have.
1879
1880=item *
4e860d0a 1881
f102b883 1882How to build it - possible changes to Makefile.PL etc.
1883
1884=item *
4e860d0a 1885
f102b883 1886How to install it.
1887
1888=item *
4e860d0a 1889
f102b883 1890Recent changes in this release, especially incompatibilities
1891
1892=item *
4e860d0a 1893
f102b883 1894Changes / enhancements you plan to make in the future.
1895
1896=back
1897
1898If the README file seems to be getting too large you may wish to
1899split out some of the sections into separate files: INSTALL,
1900Copying, ToDo etc.
1901
1902=over 4
1903
1904=item Adding a Copyright Notice.
1905
4e860d0a 1906
f102b883 1907How you choose to license your work is a personal decision.
1908The general mechanism is to assert your Copyright and then make
1909a declaration of how others may copy/use/modify your work.
1910
1911Perl, for example, is supplied with two types of licence: The GNU
1912GPL and The Artistic Licence (see the files README, Copying, and
1913Artistic). Larry has good reasons for NOT just using the GNU GPL.
1914
1915My personal recommendation, out of respect for Larry, Perl, and the
5a964f20 1916Perl community at large is to state something simply like:
f102b883 1917
1918 Copyright (c) 1995 Your Name. All rights reserved.
1919 This program is free software; you can redistribute it and/or
1920 modify it under the same terms as Perl itself.
1921
1922This statement should at least appear in the README file. You may
1923also wish to include it in a Copying file and your source files.
1924Remember to include the other words in addition to the Copyright.
1925
4e860d0a 1926=item *
1927
1928Give the module a version/issue/release number.
f102b883 1929
1930To be fully compatible with the Exporter and MakeMaker modules you
1931should store your module's version number in a non-my package
1932variable called $VERSION. This should be a floating point
1933number with at least two digits after the decimal (i.e., hundredths,
1934e.g, C<$VERSION = "0.01">). Don't use a "1.3.2" style version.
19799a22 1935See L<Exporter> for details.
f102b883 1936
1937It may be handy to add a function or method to retrieve the number.
1938Use the number in announcements and archive file names when
1939releasing the module (ModuleName-1.02.tar.Z).
1940See perldoc ExtUtils::MakeMaker.pm for details.
1941
4e860d0a 1942=item *
1943
1944How to release and distribute a module.
f102b883 1945
1946It's good idea to post an announcement of the availability of your
1947module (or the module itself if small) to the comp.lang.perl.announce
1948Usenet newsgroup. This will at least ensure very wide once-off
1949distribution.
1950
2e1d04bc 1951If possible, register the module with CPAN. You should
f102b883 1952include details of its location in your announcement.
1953
1954Some notes about ftp archives: Please use a long descriptive file
5a964f20 1955name that includes the version number. Most incoming directories
f102b883 1956will not be readable/listable, i.e., you won't be able to see your
1957file after uploading it. Remember to send your email notification
1958message as soon as possible after uploading else your file may get
1959deleted automatically. Allow time for the file to be processed
1960and/or check the file has been processed before announcing its
1961location.
1962
1963FTP Archives for Perl Modules:
1964
6cecdcac 1965Follow the instructions and links on:
f102b883 1966
4e860d0a 1967 http://www.cpan.org/modules/00modlist.long.html
1968 http://www.cpan.org/modules/04pause.html
f102b883 1969
1970or upload to one of these sites:
1971
6cecdcac 1972 https://pause.kbx.de/pause/
1973 http://pause.perl.org/pause/
f102b883 1974
6cecdcac 1975and notify <modules@perl.org>.
f102b883 1976
1977By using the WWW interface you can ask the Upload Server to mirror
1978your modules from your ftp or WWW site into your own directory on
1979CPAN!
1980
1981Please remember to send me an updated entry for the Module list!
1982
4e860d0a 1983=item *
1984
1985Take care when changing a released module.
f102b883 1986
7b8d334a 1987Always strive to remain compatible with previous released versions.
1988Otherwise try to add a mechanism to revert to the
19799a22 1989old behavior if people rely on it. Document incompatible changes.
f102b883 1990
1991=back
1992
1993=back
1994
1995=head2 Guidelines for Converting Perl 4 Library Scripts into Modules
1996
1997=over 4
1998
4e860d0a 1999=item *
2000
2001There is no requirement to convert anything.
f102b883 2002
2003If it ain't broke, don't fix it! Perl 4 library scripts should
2004continue to work with no problems. You may need to make some minor
2005changes (like escaping non-array @'s in double quoted strings) but
2006there is no need to convert a .pl file into a Module for just that.
2007
4e860d0a 2008=item *
2009
2010Consider the implications.
f102b883 2011
5a964f20 2012All Perl applications that make use of the script will need to
f102b883 2013be changed (slightly) if the script is converted into a module. Is
2014it worth it unless you plan to make other changes at the same time?
2015
4e860d0a 2016=item *
2017
2018Make the most of the opportunity.
f102b883 2019
2020If you are going to convert the script to a module you can use the
19799a22 2021opportunity to redesign the interface. The guidelines for module
2022creation above include many of the issues you should consider.
f102b883 2023
4e860d0a 2024=item *
2025
2026The pl2pm utility will get you started.
f102b883 2027
2028This utility will read *.pl files (given as parameters) and write
2029corresponding *.pm files. The pl2pm utilities does the following:
2030
2031=over 10
2032
2033=item *
4e860d0a 2034
f102b883 2035Adds the standard Module prologue lines
2036
2037=item *
4e860d0a 2038
f102b883 2039Converts package specifiers from ' to ::
2040
2041=item *
4e860d0a 2042
f102b883 2043Converts die(...) to croak(...)
2044
2045=item *
4e860d0a 2046
f102b883 2047Several other minor changes
2048
2049=back
2050
2051Being a mechanical process pl2pm is not bullet proof. The converted
2052code will need careful checking, especially any package statements.
2053Don't delete the original .pl file till the new .pm one works!
2054
2055=back
2056
2057=head2 Guidelines for Reusing Application Code
2058
2059=over 4
2060
4e860d0a 2061=item *
551e1d92 2062
2063Complete applications rarely belong in the Perl Module Library.
f102b883 2064
4e860d0a 2065=item *
551e1d92 2066
2067Many applications contain some Perl code that could be reused.
f102b883 2068
2069Help save the world! Share your code in a form that makes it easy
2070to reuse.
2071
4e860d0a 2072=item *
551e1d92 2073
2074Break-out the reusable code into one or more separate module files.
f102b883 2075
4e860d0a 2076=item *
551e1d92 2077
2078Take the opportunity to reconsider and redesign the interfaces.
2079
4e860d0a 2080=item *
f102b883 2081
551e1d92 2082In some cases the 'application' can then be reduced to a small
f102b883 2083
2084fragment of code built on top of the reusable modules. In these cases
2085the application could invoked as:
2086
5a964f20 2087 % perl -e 'use Module::Name; method(@ARGV)' ...
f102b883 2088or
5a964f20 2089 % perl -mModule::Name ... (in perl5.002 or higher)
f102b883 2090
2091=back
2092
2093=head1 NOTE
2094
2095Perl does not enforce private and public parts of its modules as you may
2096have been used to in other languages like C++, Ada, or Modula-17. Perl
2097doesn't have an infatuation with enforced privacy. It would prefer
2098that you stayed out of its living room because you weren't invited, not
2099because it has a shotgun.
2100
2101The module and its user have a contract, part of which is common law,
2102and part of which is "written". Part of the common law contract is
2103that a module doesn't pollute any namespace it wasn't asked to. The
2104written contract for the module (A.K.A. documentation) may make other
2105provisions. But then you know when you C<use RedefineTheWorld> that
2106you're redefining the world and willing to take the consequences.