-
Notifications
You must be signed in to change notification settings - Fork 2
/
Copy pathperl5120delta.html
2553 lines (1635 loc) · 115 KB
/
perl5120delta.html
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
<?xml version="1.0" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>perl5120delta - what is new for perl v5.12.0</title>
<meta http-equiv="content-type" content="text/html; charset=utf-8" />
<link rev="made" href="mailto:[email protected]" />
</head>
<body>
<ul id="index">
<li><a href="#NAME">NAME</a></li>
<li><a href="#DESCRIPTION">DESCRIPTION</a></li>
<li><a href="#Core-Enhancements">Core Enhancements</a>
<ul>
<li><a href="#New-package-NAME-VERSION-syntax">New package NAME VERSION syntax</a></li>
<li><a href="#The-...-operator">The ... operator</a></li>
<li><a href="#Implicit-strictures">Implicit strictures</a></li>
<li><a href="#Unicode-improvements">Unicode improvements</a></li>
<li><a href="#Y2038-compliance">Y2038 compliance</a></li>
<li><a href="#qr-overloading">qr overloading</a></li>
<li><a href="#Pluggable-keywords">Pluggable keywords</a></li>
<li><a href="#APIs-for-more-internals">APIs for more internals</a></li>
<li><a href="#Overridable-function-lookup">Overridable function lookup</a></li>
<li><a href="#A-proper-interface-for-pluggable-Method-Resolution-Orders">A proper interface for pluggable Method Resolution Orders</a></li>
<li><a href="#N-experimental-regex-escape">\N experimental regex escape</a></li>
<li><a href="#DTrace-support">DTrace support</a></li>
<li><a href="#Support-for-configure_requires-in-CPAN-module-metadata">Support for configure_requires in CPAN module metadata</a></li>
<li><a href="#each-keys-values-are-now-more-flexible">each, keys, values are now more flexible</a></li>
<li><a href="#when-as-a-statement-modifier">when as a statement modifier</a></li>
<li><a href="#flexibility">$, flexibility</a></li>
<li><a href="#in-when-clauses">// in when clauses</a></li>
<li><a href="#Enabling-warnings-from-your-shell-environment">Enabling warnings from your shell environment</a></li>
<li><a href="#delete-local">delete local</a></li>
<li><a href="#New-support-for-Abstract-namespace-sockets">New support for Abstract namespace sockets</a></li>
<li><a href="#bit-limit-on-substr-arguments-removed">32-bit limit on substr arguments removed</a></li>
</ul>
</li>
<li><a href="#Potentially-Incompatible-Changes">Potentially Incompatible Changes</a>
<ul>
<li><a href="#Deprecations-warn-by-default">Deprecations warn by default</a></li>
<li><a href="#Version-number-formats">Version number formats</a></li>
<li><a href="#INC-reorganization">@INC reorganization</a></li>
<li><a href="#REGEXPs-are-now-first-class">REGEXPs are now first class</a></li>
<li><a href="#Switch-statement-changes">Switch statement changes</a></li>
<li><a href="#Smart-match-changes">Smart match changes</a>
<ul>
<li><a href="#Changes-to-type-based-dispatch">Changes to type-based dispatch</a></li>
<li><a href="#Smart-match-and-overloading">Smart match and overloading</a></li>
</ul>
</li>
<li><a href="#Other-potentially-incompatible-changes">Other potentially incompatible changes</a></li>
</ul>
</li>
<li><a href="#Deprecations">Deprecations</a></li>
<li><a href="#Unicode-overhaul">Unicode overhaul</a></li>
<li><a href="#Modules-and-Pragmata">Modules and Pragmata</a>
<ul>
<li><a href="#New-Modules-and-Pragmata">New Modules and Pragmata</a></li>
<li><a href="#Updated-Pragmata">Updated Pragmata</a></li>
<li><a href="#Updated-Modules">Updated Modules</a></li>
<li><a href="#Removed-Modules-and-Pragmata">Removed Modules and Pragmata</a></li>
<li><a href="#Deprecated-Modules-and-Pragmata">Deprecated Modules and Pragmata</a></li>
</ul>
</li>
<li><a href="#Documentation">Documentation</a>
<ul>
<li><a href="#New-Documentation">New Documentation</a></li>
<li><a href="#Changes-to-Existing-Documentation">Changes to Existing Documentation</a></li>
</ul>
</li>
<li><a href="#Selected-Performance-Enhancements">Selected Performance Enhancements</a></li>
<li><a href="#Installation-and-Configuration-Improvements">Installation and Configuration Improvements</a></li>
<li><a href="#Internal-Changes">Internal Changes</a></li>
<li><a href="#Testing">Testing</a>
<ul>
<li><a href="#Testing-improvements">Testing improvements</a></li>
<li><a href="#New-Tests">New Tests</a></li>
</ul>
</li>
<li><a href="#New-or-Changed-Diagnostics">New or Changed Diagnostics</a>
<ul>
<li><a href="#New-Diagnostics">New Diagnostics</a></li>
<li><a href="#Changed-Diagnostics">Changed Diagnostics</a></li>
</ul>
</li>
<li><a href="#Utility-Changes">Utility Changes</a></li>
<li><a href="#Selected-Bug-Fixes">Selected Bug Fixes</a></li>
<li><a href="#Platform-Specific-Changes">Platform Specific Changes</a>
<ul>
<li><a href="#New-Platforms">New Platforms</a></li>
<li><a href="#Discontinued-Platforms">Discontinued Platforms</a></li>
<li><a href="#Updated-Platforms">Updated Platforms</a></li>
</ul>
</li>
<li><a href="#Known-Problems">Known Problems</a></li>
<li><a href="#Errata">Errata</a></li>
<li><a href="#Acknowledgements">Acknowledgements</a></li>
<li><a href="#Reporting-Bugs">Reporting Bugs</a></li>
<li><a href="#SEE-ALSO">SEE ALSO</a></li>
</ul>
<h1 id="NAME">NAME</h1>
<p>perl5120delta - what is new for perl v5.12.0</p>
<h1 id="DESCRIPTION">DESCRIPTION</h1>
<p>This document describes differences between the 5.10.0 release and the 5.12.0 release.</p>
<p>Many of the bug fixes in 5.12.0 are already included in the 5.10.1 maintenance release.</p>
<p>You can see the list of those changes in the 5.10.1 release notes (<a href="/cperl/perl5101delta.html">perl5101delta</a>).</p>
<h1 id="Core-Enhancements">Core Enhancements</h1>
<h2 id="New-package-NAME-VERSION-syntax">New <code>package NAME VERSION</code> syntax</h2>
<p>This new syntax allows a module author to set the $VERSION of a namespace when the namespace is declared with 'package'. It eliminates the need for <code>our $VERSION = ...</code> and similar constructs. E.g.</p>
<pre><code> package Foo::Bar 1.23;
# $Foo::Bar::VERSION == 1.23</code></pre>
<p>There are several advantages to this:</p>
<ul>
<li><p><code>$VERSION</code> is parsed in exactly the same way as <code>use NAME VERSION</code></p>
</li>
<li><p><code>$VERSION</code> is set at compile time</p>
</li>
<li><p><code>$VERSION</code> is a version object that provides proper overloading of comparison operators so comparing <code>$VERSION</code> to decimal (1.23) or dotted-decimal (v1.2.3) version numbers works correctly.</p>
</li>
<li><p>Eliminates <code>$VERSION = ...</code> and <code>eval $VERSION</code> clutter</p>
</li>
<li><p>As it requires VERSION to be a numeric literal or v-string literal, it can be statically parsed by toolchain modules without <code>eval</code> the way MM->parse_version does for <code>$VERSION = ...</code></p>
</li>
</ul>
<p>It does not break old code with only <code>package NAME</code>, but code that uses <code>package NAME VERSION</code> will need to be restricted to perl 5.12.0 or newer This is analogous to the change to <code>open</code> from two-args to three-args. Users requiring the latest Perl will benefit, and perhaps after several years, it will become a standard practice.</p>
<p>However, <code>package NAME VERSION</code> requires a new, 'strict' version number format. See <a href="#Version-number-formats">"Version number formats"</a> for details.</p>
<h2 id="The-...-operator">The <code>...</code> operator</h2>
<p>A new operator, <code>...</code>, nicknamed the Yada Yada operator, has been added. It is intended to mark placeholder code that is not yet implemented. See <a href="/cperl/perlop.html#Yada-Yada-Operator">"Yada Yada Operator" in perlop</a>.</p>
<h2 id="Implicit-strictures">Implicit strictures</h2>
<p>Using the <code>use VERSION</code> syntax with a version number greater or equal to 5.11.0 will lexically enable strictures just like <code>use strict</code> would do (in addition to enabling features.) The following:</p>
<pre><code> use 5.12.0;</code></pre>
<p>means:</p>
<pre><code> use strict;
use feature ':5.12';</code></pre>
<h2 id="Unicode-improvements">Unicode improvements</h2>
<p>Perl 5.12 comes with Unicode 5.2, the latest version available to us at the time of release. This version of Unicode was released in October 2009. See <a href="http://www.unicode.org/versions/Unicode5.2.0">http://www.unicode.org/versions/Unicode5.2.0</a> for further details about what's changed in this version of the standard. See <a href="/cperl/perlunicode.html">perlunicode</a> for instructions on installing and using other versions of Unicode.</p>
<p>Additionally, Perl's developers have significantly improved Perl's Unicode implementation. For full details, see <a href="#Unicode-overhaul">"Unicode overhaul"</a> below.</p>
<h2 id="Y2038-compliance">Y2038 compliance</h2>
<p>Perl's core time-related functions are now Y2038 compliant. (It may not mean much to you, but your kids will love it!)</p>
<h2 id="qr-overloading">qr overloading</h2>
<p>It is now possible to overload the <code>qr//</code> operator, that is, conversion to regexp, like it was already possible to overload conversion to boolean, string or number of objects. It is invoked when an object appears on the right hand side of the <code>=~</code> operator or when it is interpolated into a regexp. See <a href="/cperl/lib/overload.html">overload</a>.</p>
<h2 id="Pluggable-keywords">Pluggable keywords</h2>
<p>Extension modules can now cleanly hook into the Perl parser to define new kinds of keyword-headed expression and compound statement. The syntax following the keyword is defined entirely by the extension. This allows a completely non-Perl sublanguage to be parsed inline, with the correct ops cleanly generated.</p>
<p>See <a href="/cperl/perlapi.html#PL_keyword_plugin">"PL_keyword_plugin" in perlapi</a> for the mechanism. The Perl core source distribution also includes a new module <a>XS::APItest::KeywordRPN</a>, which implements reverse Polish notation arithmetic via pluggable keywords. This module is mainly used for test purposes, and is not normally installed, but also serves as an example of how to use the new mechanism.</p>
<p>Perl's developers consider this feature to be experimental. We may remove it or change it in a backwards-incompatible way in Perl 5.14.</p>
<h2 id="APIs-for-more-internals">APIs for more internals</h2>
<p>The lowest layers of the lexer and parts of the pad system now have C APIs available to XS extensions. These are necessary to support proper use of pluggable keywords, but have other uses too. The new APIs are experimental, and only cover a small proportion of what would be necessary to take full advantage of the core's facilities in these areas. It is intended that the Perl 5.13 development cycle will see the addition of a full range of clean, supported interfaces.</p>
<p>Perl's developers consider this feature to be experimental. We may remove it or change it in a backwards-incompatible way in Perl 5.14.</p>
<h2 id="Overridable-function-lookup">Overridable function lookup</h2>
<p>Where an extension module hooks the creation of rv2cv ops to modify the subroutine lookup process, this now works correctly for bareword subroutine calls. This means that prototypes on subroutines referenced this way will be processed correctly. (Previously bareword subroutine names were initially looked up, for parsing purposes, by an unhookable mechanism, so extensions could only properly influence subroutine names that appeared with an <code>&</code> sigil.)</p>
<h2 id="A-proper-interface-for-pluggable-Method-Resolution-Orders">A proper interface for pluggable Method Resolution Orders</h2>
<p>As of Perl 5.12.0 there is a new interface for plugging and using method resolution orders other than the default linear depth first search. The C3 method resolution order added in 5.10.0 has been re-implemented as a plugin, without changing its Perl-space interface. See <a href="/cperl/perlmroapi.html">perlmroapi</a> for more information.</p>
<h2 id="N-experimental-regex-escape"><code>\N</code> experimental regex escape</h2>
<p>Perl now supports <code>\N</code>, a new regex escape which you can think of as the inverse of <code>\n</code>. It will match any character that is not a newline, independently from the presence or absence of the single line match modifier <code>/s</code>. It is not usable within a character class. <code>\N{3}</code> means to match 3 non-newlines; <code>\N{5,}</code> means to match at least 5. <code>\N{NAME}</code> still means the character or sequence named <code>NAME</code>, but <code>NAME</code> no longer can be things like <code>3</code>, or <code>5,</code>.</p>
<p>This will break a <a href="/cperl/lib/charnames.html#CUSTOM-TRANSLATORS">custom charnames translator</a> which allows numbers for character names, as <code>\N{3}</code> will now mean to match 3 non-newline characters, and not the character whose name is <code>3</code>. (No name defined by the Unicode standard is a number, so only custom translators might be affected.)</p>
<p>Perl's developers are somewhat concerned about possible user confusion with the existing <code>\N{...}</code> construct which matches characters by their Unicode name. Consequently, this feature is experimental. We may remove it or change it in a backwards-incompatible way in Perl 5.14.</p>
<h2 id="DTrace-support">DTrace support</h2>
<p>Perl now has some support for DTrace. See "DTrace support" in <i>INSTALL</i>.</p>
<h2 id="Support-for-configure_requires-in-CPAN-module-metadata">Support for <code>configure_requires</code> in CPAN module metadata</h2>
<p>Both <code>CPAN</code> and <code>CPANPLUS</code> now support the <code>configure_requires</code> keyword in the <i>META.yml</i> metadata file included in most recent CPAN distributions. This allows distribution authors to specify configuration prerequisites that must be installed before running <i>Makefile.PL</i> or <i>Build.PL</i>.</p>
<p>See the documentation for <code>ExtUtils::MakeMaker</code> or <code>Module::Build</code> for more on how to specify <code>configure_requires</code> when creating a distribution for CPAN.</p>
<h2 id="each-keys-values-are-now-more-flexible"><code>each</code>, <code>keys</code>, <code>values</code> are now more flexible</h2>
<p>The <code>each</code>, <code>keys</code>, <code>values</code> function can now operate on arrays.</p>
<h2 id="when-as-a-statement-modifier"><code>when</code> as a statement modifier</h2>
<p><code>when</code> is now allowed to be used as a statement modifier.</p>
<h2 id="flexibility"><code>$,</code> flexibility</h2>
<p>The variable <code>$,</code> may now be tied.</p>
<h2 id="in-when-clauses">// in when clauses</h2>
<p>// now behaves like || in when clauses</p>
<h2 id="Enabling-warnings-from-your-shell-environment">Enabling warnings from your shell environment</h2>
<p>You can now set <code>-W</code> from the <code>PERL5OPT</code> environment variable</p>
<h2 id="delete-local"><code>delete local</code></h2>
<p><code>delete local</code> now allows you to locally delete a hash entry.</p>
<h2 id="New-support-for-Abstract-namespace-sockets">New support for Abstract namespace sockets</h2>
<p>Abstract namespace sockets are Linux-specific socket type that live in AF_UNIX family, slightly abusing it to be able to use arbitrary character arrays as addresses: They start with nul byte and are not terminated by nul byte, but with the length passed to the socket() system call.</p>
<h2 id="bit-limit-on-substr-arguments-removed">32-bit limit on substr arguments removed</h2>
<p>The 32-bit limit on <code>substr</code> arguments has now been removed. The full range of the system's signed and unsigned integers is now available for the <code>pos</code> and <code>len</code> arguments.</p>
<h1 id="Potentially-Incompatible-Changes">Potentially Incompatible Changes</h1>
<h2 id="Deprecations-warn-by-default">Deprecations warn by default</h2>
<p>Over the years, Perl's developers have deprecated a number of language features for a variety of reasons. Perl now defaults to issuing a warning if a deprecated language feature is used. Many of the deprecations Perl now warns you about have been deprecated for many years. You can find a list of what was deprecated in a given release of Perl in the <code>perl5xxdelta.pod</code> file for that release.</p>
<p>To disable this feature in a given lexical scope, you should use <code>no warnings 'deprecated';</code> For information about which language features are deprecated and explanations of various deprecation warnings, please see <a href="/cperl/perldiag.html">perldiag</a>. See <a href="#Deprecations">"Deprecations"</a> below for the list of features and modules Perl's developers have deprecated as part of this release.</p>
<h2 id="Version-number-formats">Version number formats</h2>
<p>Acceptable version number formats have been formalized into "strict" and "lax" rules. <code>package NAME VERSION</code> takes a strict version number. <code>UNIVERSAL::VERSION</code> and the <a href="/cperl/lib/version.html">version</a> object constructors take lax version numbers. Providing an invalid version will result in a fatal error. The version argument in <code>use NAME VERSION</code> is first parsed as a numeric literal or v-string and then passed to <code>UNIVERSAL::VERSION</code> (and must then pass the "lax" format test).</p>
<p>These formats are documented fully in the <a href="/cperl/lib/version.html">version</a> module. To a first approximation, a "strict" version number is a positive decimal number (integer or decimal-fraction) without exponentiation or else a dotted-decimal v-string with a leading 'v' character and at least three components. A "lax" version number allows v-strings with fewer than three components or without a leading 'v'. Under "lax" rules, both decimal and dotted-decimal versions may have a trailing "alpha" component separated by an underscore character after a fractional or dotted-decimal component.</p>
<p>The <a href="/cperl/lib/version.html">version</a> module adds <code>version::is_strict</code> and <code>version::is_lax</code> functions to check a scalar against these rules.</p>
<h2 id="INC-reorganization">@INC reorganization</h2>
<p>In <code>@INC</code>, <code>ARCHLIB</code> and <code>PRIVLIB</code> now occur after the current version's <code>site_perl</code> and <code>vendor_perl</code>. Modules installed into <code>site_perl</code> and <code>vendor_perl</code> will now be loaded in preference to those installed in <code>ARCHLIB</code> and <code>PRIVLIB</code>.</p>
<h2 id="REGEXPs-are-now-first-class">REGEXPs are now first class</h2>
<p>Internally, Perl now treats compiled regular expressions (such as those created with <code>qr//</code>) as first class entities. Perl modules which serialize, deserialize or otherwise have deep interaction with Perl's internal data structures need to be updated for this change. Most affected CPAN modules have already been updated as of this writing.</p>
<h2 id="Switch-statement-changes">Switch statement changes</h2>
<p>The <code>given</code>/<code>when</code> switch statement handles complex statements better than Perl 5.10.0 did (These enhancements are also available in 5.10.1 and subsequent 5.10 releases.) There are two new cases where <code>when</code> now interprets its argument as a boolean, instead of an expression to be used in a smart match:</p>
<dl>
<dt id="flip-flop-operators">flip-flop operators</dt>
<dd>
<p>The <code>..</code> and <code>...</code> flip-flop operators are now evaluated in boolean context, following their usual semantics; see <a href="/cperl/perlop.html#Range-Operators">"Range Operators" in perlop</a>.</p>
<p>Note that, as in perl 5.10.0, <code>when (1..10)</code> will not work to test whether a given value is an integer between 1 and 10; you should use <code>when ([1..10])</code> instead (note the array reference).</p>
<p>However, contrary to 5.10.0, evaluating the flip-flop operators in boolean context ensures it can now be useful in a <code>when()</code>, notably for implementing bistable conditions, like in:</p>
<pre><code> when (/^=begin/ .. /^=end/) {
# do something
}</code></pre>
</dd>
<dt id="defined-or-operator">defined-or operator</dt>
<dd>
<p>A compound expression involving the defined-or operator, as in <code>when (expr1 // expr2)</code>, will be treated as boolean if the first expression is boolean. (This just extends the existing rule that applies to the regular or operator, as in <code>when (expr1 || expr2)</code>.)</p>
</dd>
</dl>
<h2 id="Smart-match-changes">Smart match changes</h2>
<p>Since Perl 5.10.0, Perl's developers have made a number of changes to the smart match operator. These, of course, also alter the behaviour of the switch statements where smart matching is implicitly used. These changes were also made for the 5.10.1 release, and will remain in subsequent 5.10 releases.</p>
<h3 id="Changes-to-type-based-dispatch">Changes to type-based dispatch</h3>
<p>The smart match operator <code>~~</code> is no longer commutative. The behaviour of a smart match now depends primarily on the type of its right hand argument. Moreover, its semantics have been adjusted for greater consistency or usefulness in several cases. While the general backwards compatibility is maintained, several changes must be noted:</p>
<ul>
<li><p>Code references with an empty prototype are no longer treated specially. They are passed an argument like the other code references (even if they choose to ignore it).</p>
</li>
<li><p><code>%hash ~~ sub {}</code> and <code>@array ~~ sub {}</code> now test that the subroutine returns a true value for each key of the hash (or element of the array), instead of passing the whole hash or array as a reference to the subroutine.</p>
</li>
<li><p>Due to the commutativity breakage, code references are no longer treated specially when appearing on the left of the <code>~~</code> operator, but like any vulgar scalar.</p>
</li>
<li><p><code>undef ~~ %hash</code> is always false (since <code>undef</code> can't be a key in a hash). No implicit conversion to <code>""</code> is done (as was the case in perl 5.10.0).</p>
</li>
<li><p><code>$scalar ~~ @array</code> now always distributes the smart match across the elements of the array. It's true if one element in @array verifies <code>$scalar ~~ $element</code>. This is a generalization of the old behaviour that tested whether the array contained the scalar.</p>
</li>
</ul>
<p>The full dispatch table for the smart match operator is given in <a href="/cperl/perlsyn.html#Smart-matching-in-detail">"Smart matching in detail" in perlsyn</a>.</p>
<h3 id="Smart-match-and-overloading">Smart match and overloading</h3>
<p>According to the rule of dispatch based on the rightmost argument type, when an object overloading <code>~~</code> appears on the right side of the operator, the overload routine will always be called (with a 3rd argument set to a true value, see <a href="/cperl/lib/overload.html">overload</a>.) However, when the object will appear on the left, the overload routine will be called only when the rightmost argument is a simple scalar. This way, distributivity of smart match across arrays is not broken, as well as the other behaviours with complex types (coderefs, hashes, regexes). Thus, writers of overloading routines for smart match mostly need to worry only with comparing against a scalar, and possibly with stringification overloading; the other common cases will be automatically handled consistently.</p>
<p><code>~~</code> will now refuse to work on objects that do not overload it (in order to avoid relying on the object's underlying structure). (However, if the object overloads the stringification or the numification operators, and if overload fallback is active, it will be used instead, as usual.)</p>
<h2 id="Other-potentially-incompatible-changes">Other potentially incompatible changes</h2>
<ul>
<li><p>The definitions of a number of Unicode properties have changed to match those of the current Unicode standard. These are listed above under <a href="#Unicode-overhaul">"Unicode overhaul"</a>. This change may break code that expects the old definitions.</p>
</li>
<li><p>The boolkeys op has moved to the group of hash ops. This breaks binary compatibility.</p>
</li>
<li><p>Filehandles are now always blessed into <code>IO::File</code>.</p>
<p>The previous behaviour was to bless Filehandles into <a href="/cperl/lib/FileHandle.html">FileHandle</a> (an empty proxy class) if it was loaded into memory and otherwise to bless them into <code>IO::Handle</code>.</p>
</li>
<li><p>The semantics of <code>use feature :5.10*</code> have changed slightly. See <a href="#Modules-and-Pragmata">"Modules and Pragmata"</a> for more information.</p>
</li>
<li><p>Perl's developers now use git, rather than Perforce. This should be a purely internal change only relevant to people actively working on the core. However, you may see minor difference in perl as a consequence of the change. For example in some of details of the output of <code>perl -V</code>. See <a href="/cperl/perlrepository.html">perlrepository</a> for more information.</p>
</li>
<li><p>As part of the <code>Test::Harness</code> 2.x to 3.x upgrade, the experimental <code>Test::Harness::Straps</code> module has been removed. See <a href="#Modules-and-Pragmata">"Modules and Pragmata"</a> for more details.</p>
</li>
<li><p>As part of the <code>ExtUtils::MakeMaker</code> upgrade, the <code>ExtUtils::MakeMaker::bytes</code> and <code>ExtUtils::MakeMaker::vmsish</code> modules have been removed from this distribution.</p>
</li>
<li><p><code>Module::CoreList</code> no longer contains the <code>%:patchlevel</code> hash.</p>
</li>
<li><p><code>length undef</code> now returns undef.</p>
</li>
<li><p>Unsupported private C API functions are now declared "static" to prevent leakage to Perl's public API.</p>
</li>
<li><p>To support the bootstrapping process, <i>miniperl</i> no longer builds with UTF-8 support in the regexp engine.</p>
<p>This allows a build to complete with PERL_UNICODE set and a UTF-8 locale. Without this there's a bootstrapping problem, as miniperl can't load the UTF-8 components of the regexp engine, because they're not yet built.</p>
</li>
<li><p><i>miniperl</i>'s @INC is now restricted to just <code>-I...</code>, the split of <code>$ENV{PERL5LIB}</code>, and "<code>.</code>"</p>
</li>
<li><p>A space or a newline is now required after a <code>"#line XXX"</code> directive.</p>
</li>
<li><p>Tied filehandles now have an additional method EOF which provides the EOF type.</p>
</li>
<li><p>To better match all other flow control statements, <code>foreach</code> may no longer be used as an attribute.</p>
</li>
<li><p>Perl's command-line switch "-P", which was deprecated in version 5.10.0, has now been removed. The CPAN module <code>Filter::cpp</code> can be used as an alternative.</p>
</li>
</ul>
<h1 id="Deprecations">Deprecations</h1>
<p>From time to time, Perl's developers find it necessary to deprecate features or modules we've previously shipped as part of the core distribution. We are well aware of the pain and frustration that a backwards-incompatible change to Perl can cause for developers building or maintaining software in Perl. You can be sure that when we deprecate a functionality or syntax, it isn't a choice we make lightly. Sometimes, we choose to deprecate functionality or syntax because it was found to be poorly designed or implemented. Sometimes, this is because they're holding back other features or causing performance problems. Sometimes, the reasons are more complex. Wherever possible, we try to keep deprecated functionality available to developers in its previous form for at least one major release. So long as a deprecated feature isn't actively disrupting our ability to maintain and extend Perl, we'll try to leave it in place as long as possible.</p>
<p>The following items are now deprecated:</p>
<dl>
<dt id="suidperl">suidperl</dt>
<dd>
<p><code>suidperl</code> is no longer part of Perl. It used to provide a mechanism to emulate setuid permission bits on systems that don't support it properly.</p>
</dd>
<dt id="Use-of-:-to-mean-an-empty-attribute-list">Use of <code>:=</code> to mean an empty attribute list</dt>
<dd>
<p>An accident of Perl's parser meant that these constructions were all equivalent:</p>
<pre><code> my $pi := 4;
my $pi : = 4;
my $pi : = 4;</code></pre>
<p>with the <code>:</code> being treated as the start of an attribute list, which ends before the <code>=</code>. As whitespace is not significant here, all are parsed as an empty attribute list, hence all the above are equivalent to, and better written as</p>
<pre><code> my $pi = 4;</code></pre>
<p>because no attribute processing is done for an empty list.</p>
<p>As is, this meant that <code>:=</code> cannot be used as a new token, without silently changing the meaning of existing code. Hence that particular form is now deprecated, and will become a syntax error. If it is absolutely necessary to have empty attribute lists (for example, because of a code generator) then avoid the warning by adding a space before the <code>=</code>.</p>
</dd>
<dt id="UNIVERSAL-import"><code>UNIVERSAL->import()</code></dt>
<dd>
<p>The method <code>UNIVERSAL->import()</code> is now deprecated. Attempting to pass import arguments to a <code>use UNIVERSAL</code> statement will result in a deprecation warning.</p>
</dd>
<dt id="Use-of-goto-to-jump-into-a-construct">Use of "goto" to jump into a construct</dt>
<dd>
<p>Using <code>goto</code> to jump from an outer scope into an inner scope is now deprecated. This rare use case was causing problems in the implementation of scopes.</p>
</dd>
<dt id="Custom-character-names-in-N-name-that-dont-look-like-names">Custom character names in \N{name} that don't look like names</dt>
<dd>
<p>In <code>\N{<i>name</i>}</code>, <i>name</i> can be just about anything. The standard Unicode names have a very limited domain, but a custom name translator could create names that are, for example, made up entirely of punctuation symbols. It is now deprecated to make names that don't begin with an alphabetic character, and aren't alphanumeric or contain other than a very few other characters, namely spaces, dashes, parentheses and colons. Because of the added meaning of <code>\N</code> (See <a href="#N-experimental-regex-escape">"<code>\N</code> experimental regex escape"</a>), names that look like curly brace -enclosed quantifiers won't work. For example, <code>\N{3,4}</code> now means to match 3 to 4 non-newlines; before a custom name <code>3,4</code> could have been created.</p>
</dd>
<dt id="Deprecated-Modules">Deprecated Modules</dt>
<dd>
<p>The following modules will be removed from the core distribution in a future release, and should be installed from CPAN instead. Distributions on CPAN which require these should add them to their prerequisites. The core versions of these modules warnings will issue a deprecation warning.</p>
<p>If you ship a packaged version of Perl, either alone or as part of a larger system, then you should carefully consider the repercussions of core module deprecations. You may want to consider shipping your default build of Perl with packages for some or all deprecated modules which install into <code>vendor</code> or <code>site</code> perl library directories. This will inhibit the deprecation warnings.</p>
<p>Alternatively, you may want to consider patching <i>lib/deprecate.pm</i> to provide deprecation warnings specific to your packaging system or distribution of Perl, consistent with how your packaging system or distribution manages a staged transition from a release where the installation of a single package provides the given functionality, to a later release where the system administrator needs to know to install multiple packages to get that same functionality.</p>
<p>You can silence these deprecation warnings by installing the modules in question from CPAN. To install the latest version of all of them, just install <code>Task::Deprecations::5_12</code>.</p>
<dl>
<dt id="Class::ISA"><a>Class::ISA</a></dt>
<dd>
</dd>
<dt id="Pod::Plainer"><a>Pod::Plainer</a></dt>
<dd>
</dd>
<dt id="Shell"><a>Shell</a></dt>
<dd>
</dd>
<dt id="Switch"><a>Switch</a></dt>
<dd>
<p>Switch is buggy and should be avoided. You may find Perl's new <code>given</code>/<code>when</code> feature a suitable replacement. See <a href="/cperl/perlsyn.html#Switch-statements">"Switch statements" in perlsyn</a> for more information.</p>
</dd>
</dl>
</dd>
<dt id="Assignment-to">Assignment to $[</dt>
<dd>
</dd>
<dt id="Use-of-the-attribute-:locked-on-subroutines">Use of the attribute :locked on subroutines</dt>
<dd>
</dd>
<dt id="Use-of-locked-with-the-attributes-pragma">Use of "locked" with the attributes pragma</dt>
<dd>
</dd>
<dt id="Use-of-unique-with-the-attributes-pragma">Use of "unique" with the attributes pragma</dt>
<dd>
</dd>
<dt id="Perl_pmflag">Perl_pmflag</dt>
<dd>
<p><code>Perl_pmflag</code> is no longer part of Perl's public API. Calling it now generates a deprecation warning, and it will be removed in a future release. Although listed as part of the API, it was never documented, and only ever used in <i>toke.c</i>, and prior to 5.10, <i>regcomp.c</i>. In core, it has been replaced by a static function.</p>
</dd>
<dt id="Numerous-Perl-4-era-libraries">Numerous Perl 4-era libraries</dt>
<dd>
<p><i>termcap.pl</i>, <i>tainted.pl</i>, <i>stat.pl</i>, <i>shellwords.pl</i>, <i>pwd.pl</i>, <i>open3.pl</i>, <i>open2.pl</i>, <i>newgetopt.pl</i>, <i>look.pl</i>, <i>find.pl</i>, <i>finddepth.pl</i>, <i>importenv.pl</i>, <i>hostname.pl</i>, <i>getopts.pl</i>, <i>getopt.pl</i>, <i>getcwd.pl</i>, <i>flush.pl</i>, <i>fastcwd.pl</i>, <i>exceptions.pl</i>, <i>ctime.pl</i>, <i>complete.pl</i>, <i>cacheout.pl</i>, <i>bigrat.pl</i>, <i>bigint.pl</i>, <i>bigfloat.pl</i>, <i>assert.pl</i>, <i>abbrev.pl</i>, <i>dotsh.pl</i>, and <i>timelocal.pl</i> are all now deprecated. Earlier, Perl's developers intended to remove these libraries from Perl's core for the 5.14.0 release.</p>
<p>During final testing before the release of 5.12.0, several developers discovered current production code using these ancient libraries, some inside the Perl core itself. Accordingly, the pumpking granted them a stay of execution. They will begin to warn about their deprecation in the 5.14.0 release and will be removed in the 5.16.0 release.</p>
</dd>
</dl>
<h1 id="Unicode-overhaul">Unicode overhaul</h1>
<p>Perl's developers have made a concerted effort to update Perl to be in sync with the latest Unicode standard. Changes for this include:</p>
<p>Perl can now handle every Unicode character property. New documentation, <a href="/cperl/perluniprops.html">perluniprops</a>, lists all available non-Unihan character properties. By default, perl does not expose Unihan, deprecated or Unicode-internal properties. See below for more details on these; there is also a section in the pod listing them, and explaining why they are not exposed.</p>
<p>Perl now fully supports the Unicode compound-style of using <code>=</code> and <code>:</code> in writing regular expressions: <code>\p{property=value}</code> and <code>\p{property:value}</code> (both of which mean the same thing).</p>
<p>Perl now fully supports the Unicode loose matching rules for text between the braces in <code>\p{...}</code> constructs. In addition, Perl allows underscores between digits of numbers.</p>
<p>Perl now accepts all the Unicode-defined synonyms for properties and property values.</p>
<p><code>qr/\X/</code>, which matches a Unicode logical character, has been expanded to work better with various Asian languages. It now is defined as an <i>extended grapheme cluster</i>. (See <a href="http://www.unicode.org/reports/tr29/">http://www.unicode.org/reports/tr29/</a>). Anything matched previously and that made sense will continue to be accepted. Additionally:</p>
<ul>
<li><p><code>\X</code> will not break apart a <code><span style="white-space: nowrap;">CR LF</span></code> sequence.</p>
</li>
<li><p><code>\X</code> will now match a sequence which includes the <code>ZWJ</code> and <code>ZWNJ</code> characters.</p>
</li>
<li><p><code>\X</code> will now always match at least one character, including an initial mark. Marks generally come after a base character, but it is possible in Unicode to have them in isolation, and <code>\X</code> will now handle that case, for example at the beginning of a line, or after a <code>ZWSP</code>. And this is the part where <code>\X</code> doesn't match the things that it used to that don't make sense. Formerly, for example, you could have the nonsensical case of an accented LF.</p>
</li>
<li><p><code>\X</code> will now match a (Korean) Hangul syllable sequence, and the Thai and Lao exception cases.</p>
</li>
</ul>
<p>Otherwise, this change should be transparent for the non-affected languages.</p>
<p><code>\p{...}</code> matches using the Canonical_Combining_Class property were completely broken in previous releases of Perl. They should now work correctly.</p>
<p>Before Perl 5.12, the Unicode <code>Decomposition_Type=Compat</code> property and a Perl extension had the same name, which led to neither matching all the correct values (with more than 100 mistakes in one, and several thousand in the other). The Perl extension has now been renamed to be <code>Decomposition_Type=Noncanonical</code> (short: <code>dt=noncanon</code>). It has the same meaning as was previously intended, namely the union of all the non-canonical Decomposition types, with Unicode <code>Compat</code> being just one of those.</p>
<p><code>\p{Decomposition_Type=Canonical}</code> now includes the Hangul syllables.</p>
<p><code>\p{Uppercase}</code> and <code>\p{Lowercase}</code> now work as the Unicode standard says they should. This means they each match a few more characters than they used to.</p>
<p><code>\p{Cntrl}</code> now matches the same characters as <code>\p{Control}</code>. This means it no longer will match Private Use (gc=co), Surrogates (gc=cs), nor Format (gc=cf) code points. The Format code points represent the biggest possible problem. All but 36 of them are either officially deprecated or strongly discouraged from being used. Of those 36, likely the most widely used are the soft hyphen (U+00AD), and BOM, ZWSP, ZWNJ, WJ, and similar characters, plus bidirectional controls.</p>
<p><code>\p{Alpha}</code> now matches the same characters as <code>\p{Alphabetic}</code>. Before 5.12, Perl's definition included a number of things that aren't really alpha (all marks) while omitting many that were. The definitions of <code>\p{Alnum}</code> and <code>\p{Word}</code> depend on Alpha's definition and have changed accordingly.</p>
<p><code>\p{Word}</code> no longer incorrectly matches non-word characters such as fractions.</p>
<p><code>\p{Print}</code> no longer matches the line control characters: Tab, LF, CR, FF, VT, and NEL. This brings it in line with standards and the documentation.</p>
<p><code>\p{XDigit}</code> now matches the same characters as <code>\p{Hex_Digit}</code>. This means that in addition to the characters it currently matches, <code>[A-Fa-f0-9]</code>, it will also match the 22 fullwidth equivalents, for example U+FF10: FULLWIDTH DIGIT ZERO.</p>
<p>The Numeric type property has been extended to include the Unihan characters.</p>
<p>There is a new Perl extension, the 'Present_In', or simply 'In', property. This is an extension of the Unicode Age property, but <code>\p{In=5.0}</code> matches any code point whose usage has been determined <i>as of</i> Unicode version 5.0. The <code>\p{Age=5.0}</code> only matches code points added in <i>precisely</i> version 5.0.</p>
<p>A number of properties now have the correct values for unassigned code points. The affected properties are Bidi_Class, East_Asian_Width, Joining_Type, Decomposition_Type, Hangul_Syllable_Type, Numeric_Type, and Line_Break.</p>
<p>The Default_Ignorable_Code_Point, ID_Continue, and ID_Start properties are now up to date with current Unicode definitions.</p>
<p>Earlier versions of Perl erroneously exposed certain properties that are supposed to be Unicode internal-only. Use of these in regular expressions will now generate, if enabled, a deprecation warning message. The properties are: Other_Alphabetic, Other_Default_Ignorable_Code_Point, Other_Grapheme_Extend, Other_ID_Continue, Other_ID_Start, Other_Lowercase, Other_Math, and Other_Uppercase.</p>
<p>It is now possible to change which Unicode properties Perl understands on a per-installation basis. As mentioned above, certain properties are turned off by default. These include all the Unihan properties (which should be accessible via the CPAN module Unicode::Unihan) and any deprecated or Unicode internal-only property that Perl has never exposed.</p>
<p>The generated files in the <code>lib/unicore/To</code> directory are now more clearly marked as being stable, directly usable by applications. New hash entries in them give the format of the normal entries, which allows for easier machine parsing. Perl can generate files in this directory for any property, though most are suppressed. You can find instructions for changing which are written in <a href="/cperl/perluniprops.html">perluniprops</a>.</p>
<h1 id="Modules-and-Pragmata">Modules and Pragmata</h1>
<h2 id="New-Modules-and-Pragmata">New Modules and Pragmata</h2>
<dl>
<dt id="autodie"><code>autodie</code></dt>
<dd>
<p><code>autodie</code> is a new lexically-scoped alternative for the <code>Fatal</code> module. The bundled version is 2.06_01. Note that in this release, using a string eval when <code>autodie</code> is in effect can cause the autodie behaviour to leak into the surrounding scope. See <a href="/cperl/lib/autodie.html#BUGS">"BUGS" in autodie</a> for more details.</p>
<p>Version 2.06_01 has been added to the Perl core.</p>
</dd>
<dt id="Compress::Raw::Bzip2"><code>Compress::Raw::Bzip2</code></dt>
<dd>
<p>Version 2.024 has been added to the Perl core.</p>
</dd>
<dt id="overloading"><code>overloading</code></dt>
<dd>
<p><code>overloading</code> allows you to lexically disable or enable overloading for some or all operations.</p>
<p>Version 0.001 has been added to the Perl core.</p>
</dd>
<dt id="parent"><code>parent</code></dt>
<dd>
<p><code>parent</code> establishes an ISA relationship with base classes at compile time. It provides the key feature of <code>base</code> without further unwanted behaviors.</p>
<p>Version 0.223 has been added to the Perl core.</p>
</dd>
<dt id="Parse::CPAN::Meta"><code>Parse::CPAN::Meta</code></dt>
<dd>
<p>Version 1.40 has been added to the Perl core.</p>
</dd>
<dt id="VMS::DCLsym"><code>VMS::DCLsym</code></dt>
<dd>
<p>Version 1.03 has been added to the Perl core.</p>
</dd>
<dt id="VMS::Stdio"><code>VMS::Stdio</code></dt>
<dd>
<p>Version 2.4 has been added to the Perl core.</p>
</dd>
<dt id="XS::APItest::KeywordRPN"><code>XS::APItest::KeywordRPN</code></dt>
<dd>
<p>Version 0.003 has been added to the Perl core.</p>
</dd>
</dl>
<h2 id="Updated-Pragmata">Updated Pragmata</h2>
<dl>
<dt id="base"><code>base</code></dt>
<dd>
<p>Upgraded from version 2.13 to 2.15.</p>
</dd>
<dt id="bignum"><code>bignum</code></dt>
<dd>
<p>Upgraded from version 0.22 to 0.23.</p>
</dd>
<dt id="charnames"><code>charnames</code></dt>
<dd>
<p><code>charnames</code> now contains the Unicode <i>NameAliases.txt</i> database file. This has the effect of adding some extra <code>\N</code> character names that formerly wouldn't have been recognised; for example, <code>"\N{LATIN CAPITAL LETTER GHA}"</code>.</p>
<p>Upgraded from version 1.06 to 1.07.</p>
</dd>
<dt id="constant"><code>constant</code></dt>
<dd>
<p>Upgraded from version 1.13 to 1.20.</p>
</dd>
<dt id="diagnostics"><code>diagnostics</code></dt>
<dd>
<p><code>diagnostics</code> now supports %.0f formatting internally.</p>
<p><code>diagnostics</code> no longer suppresses <code>Use of uninitialized value in range (or flip)</code> warnings. [perl #71204]</p>
<p>Upgraded from version 1.17 to 1.19.</p>
</dd>
<dt id="feature"><code>feature</code></dt>
<dd>
<p>In <code>feature</code>, the meaning of the <code>:5.10</code> and <code>:5.10.X</code> feature bundles has changed slightly. The last component, if any (i.e. <code>X</code>) is simply ignored. This is predicated on the assumption that new features will not, in general, be added to maintenance releases. So <code>:5.10</code> and <code>:5.10.X</code> have identical effect. This is a change to the behaviour documented for 5.10.0.</p>
<p><code>feature</code> now includes the <code>unicode_strings</code> feature:</p>
<pre><code> use feature "unicode_strings";</code></pre>
<p>This pragma turns on Unicode semantics for the case-changing operations (<code>uc</code>, <code>lc</code>, <code>ucfirst</code>, <code>lcfirst</code>) on strings that don't have the internal UTF-8 flag set, but that contain single-byte characters between 128 and 255.</p>
<p>Upgraded from version 1.11 to 1.16.</p>
</dd>
<dt id="less"><code>less</code></dt>
<dd>
<p><code>less</code> now includes the <code>stash_name</code> method to allow subclasses of <code>less</code> to pick where in %^H to store their stash.</p>
<p>Upgraded from version 0.02 to 0.03.</p>
</dd>
<dt id="lib"><code>lib</code></dt>
<dd>
<p>Upgraded from version 0.5565 to 0.62.</p>
</dd>
<dt id="mro"><code>mro</code></dt>
<dd>
<p><code>mro</code> is now implemented as an XS extension. The documented interface has not changed. Code relying on the implementation detail that some <code>mro::</code> methods happened to be available at all times gets to "keep both pieces".</p>
<p>Upgraded from version 1.00 to 1.02.</p>
</dd>
<dt id="overload"><code>overload</code></dt>
<dd>
<p><code>overload</code> now allow overloading of 'qr'.</p>
<p>Upgraded from version 1.06 to 1.10.</p>
</dd>
<dt id="threads"><code>threads</code></dt>
<dd>
<p>Upgraded from version 1.67 to 1.75.</p>
</dd>
<dt id="threads::shared"><code>threads::shared</code></dt>
<dd>
<p>Upgraded from version 1.14 to 1.32.</p>
</dd>
<dt id="version"><code>version</code></dt>
<dd>
<p><code>version</code> now has support for <a href="#Version-number-formats">"Version number formats"</a> as described earlier in this document and in its own documentation.</p>
<p>Upgraded from version 0.74 to 0.82.</p>
</dd>
<dt id="warnings"><code>warnings</code></dt>
<dd>
<p><code>warnings</code> has a new <code>warnings::fatal_enabled()</code> function. It also includes a new <code>illegalproto</code> warning category. See also <a href="#New-or-Changed-Diagnostics">"New or Changed Diagnostics"</a> for this change.</p>
<p>Upgraded from version 1.06 to 1.09.</p>
</dd>
</dl>
<h2 id="Updated-Modules">Updated Modules</h2>
<dl>
<dt id="Archive::Extract"><code>Archive::Extract</code></dt>
<dd>
<p>Upgraded from version 0.24 to 0.38.</p>
</dd>
<dt id="Archive::Tar"><code>Archive::Tar</code></dt>
<dd>
<p>Upgraded from version 1.38 to 1.54.</p>
</dd>
<dt id="Attribute::Handlers"><code>Attribute::Handlers</code></dt>
<dd>
<p>Upgraded from version 0.79 to 0.87.</p>
</dd>
<dt id="AutoLoader"><code>AutoLoader</code></dt>
<dd>
<p>Upgraded from version 5.63 to 5.70.</p>
</dd>
<dt id="B::Concise"><code>B::Concise</code></dt>
<dd>
<p>Upgraded from version 0.74 to 0.78.</p>
</dd>
<dt id="B::Debug"><code>B::Debug</code></dt>
<dd>
<p>Upgraded from version 1.05 to 1.12.</p>
</dd>
<dt id="B::Deparse"><code>B::Deparse</code></dt>
<dd>
<p>Upgraded from version 0.83 to 0.96.</p>
</dd>
<dt id="B::Lint"><code>B::Lint</code></dt>
<dd>
<p>Upgraded from version 1.09 to 1.11_01.</p>
</dd>
<dt id="CGI"><code>CGI</code></dt>
<dd>
<p>Upgraded from version 3.29 to 3.48.</p>
</dd>
<dt id="Class::ISA1"><code>Class::ISA</code></dt>
<dd>
<p>Upgraded from version 0.33 to 0.36.</p>
<p>NOTE: <code>Class::ISA</code> is deprecated and may be removed from a future version of Perl.</p>
</dd>
<dt id="Compress::Raw::Zlib"><code>Compress::Raw::Zlib</code></dt>
<dd>
<p>Upgraded from version 2.008 to 2.024.</p>
</dd>
<dt id="CPAN"><code>CPAN</code></dt>
<dd>
<p>Upgraded from version 1.9205 to 1.94_56.</p>
</dd>
<dt id="CPANPLUS"><code>CPANPLUS</code></dt>
<dd>
<p>Upgraded from version 0.84 to 0.90.</p>
</dd>
<dt id="CPANPLUS::Dist::Build"><code>CPANPLUS::Dist::Build</code></dt>
<dd>
<p>Upgraded from version 0.06_02 to 0.46.</p>
</dd>
<dt id="Data::Dumper"><code>Data::Dumper</code></dt>
<dd>
<p>Upgraded from version 2.121_14 to 2.125.</p>
</dd>
<dt id="DB_File"><code>DB_File</code></dt>
<dd>
<p>Upgraded from version 1.816_1 to 1.820.</p>
</dd>
<dt id="Devel::PPPort"><code>Devel::PPPort</code></dt>
<dd>
<p>Upgraded from version 3.13 to 3.19.</p>
</dd>
<dt id="Digest"><code>Digest</code></dt>
<dd>
<p>Upgraded from version 1.15 to 1.16.</p>
</dd>
<dt id="Digest::MD5"><code>Digest::MD5</code></dt>
<dd>
<p>Upgraded from version 2.36_01 to 2.39.</p>
</dd>
<dt id="Digest::SHA"><code>Digest::SHA</code></dt>
<dd>
<p>Upgraded from version 5.45 to 5.47.</p>
</dd>
<dt id="Encode"><code>Encode</code></dt>
<dd>
<p>Upgraded from version 2.23 to 2.39.</p>
</dd>
<dt id="Exporter"><code>Exporter</code></dt>
<dd>
<p>Upgraded from version 5.62 to 5.64_01.</p>
</dd>
<dt id="ExtUtils::CBuilder"><code>ExtUtils::CBuilder</code></dt>
<dd>
<p>Upgraded from version 0.21 to 0.27.</p>
</dd>
<dt id="ExtUtils::Command"><code>ExtUtils::Command</code></dt>
<dd>
<p>Upgraded from version 1.13 to 1.16.</p>
</dd>
<dt id="ExtUtils::Constant"><code>ExtUtils::Constant</code></dt>
<dd>
<p>Upgraded from version 0.2 to 0.22.</p>
</dd>
<dt id="ExtUtils::Install"><code>ExtUtils::Install</code></dt>
<dd>
<p>Upgraded from version 1.44 to 1.55.</p>
</dd>
<dt id="ExtUtils::MakeMaker"><code>ExtUtils::MakeMaker</code></dt>
<dd>
<p>Upgraded from version 6.42 to 6.56.</p>
</dd>
<dt id="ExtUtils::Manifest"><code>ExtUtils::Manifest</code></dt>
<dd>
<p>Upgraded from version 1.51_01 to 1.57.</p>
</dd>
<dt id="ExtUtils::ParseXS"><code>ExtUtils::ParseXS</code></dt>
<dd>
<p>Upgraded from version 2.18_02 to 2.21.</p>
</dd>
<dt id="File::Fetch"><code>File::Fetch</code></dt>
<dd>
<p>Upgraded from version 0.14 to 0.24.</p>
</dd>
<dt id="File::Path"><code>File::Path</code></dt>
<dd>
<p>Upgraded from version 2.04 to 2.08_01.</p>
</dd>
<dt id="File::Temp"><code>File::Temp</code></dt>
<dd>
<p>Upgraded from version 0.18 to 0.22.</p>
</dd>
<dt id="Filter::Simple"><code>Filter::Simple</code></dt>
<dd>
<p>Upgraded from version 0.82 to 0.84.</p>
</dd>
<dt id="Filter::Util::Call"><code>Filter::Util::Call</code></dt>
<dd>
<p>Upgraded from version 1.07 to 1.08.</p>
</dd>
<dt id="Getopt::Long"><code>Getopt::Long</code></dt>
<dd>
<p>Upgraded from version 2.37 to 2.38.</p>
</dd>
<dt id="IO"><code>IO</code></dt>
<dd>
<p>Upgraded from version 1.23_01 to 1.25_02.</p>
</dd>
<dt id="IO::Zlib"><code>IO::Zlib</code></dt>
<dd>
<p>Upgraded from version 1.07 to 1.10.</p>
</dd>
<dt id="IPC::Cmd"><code>IPC::Cmd</code></dt>
<dd>
<p>Upgraded from version 0.40_1 to 0.54.</p>
</dd>
<dt id="IPC::SysV"><code>IPC::SysV</code></dt>
<dd>
<p>Upgraded from version 1.05 to 2.01.</p>
</dd>
<dt id="Locale::Maketext"><code>Locale::Maketext</code></dt>
<dd>
<p>Upgraded from version 1.12 to 1.14.</p>
</dd>
<dt id="Locale::Maketext::Simple"><code>Locale::Maketext::Simple</code></dt>