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1=encoding utf8
2
3=head1 NAME
4
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5[ this is a template for a new perldelta file. Any text flagged as XXX needs
6to be processed before release. ]
7
8perldelta - what is new for perl v5.31.5
d407e309 9
862f380b 10=head1 DESCRIPTION
261e14b0 11
74c14c97 12This document describes differences between the 5.31.4 release and the 5.31.5
862f380b 13release.
261e14b0 14
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15If you are upgrading from an earlier release such as 5.31.3, first read
16L<perl5314delta>, which describes differences between 5.31.3 and 5.31.4.
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17
18=head1 Notice
19
74c14c97 20XXX Any important notices here
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21
22=head1 Core Enhancements
23
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24XXX New core language features go here. Summarize user-visible core language
25enhancements. Particularly prominent performance optimisations could go
26here, but most should go in the L</Performance Enhancements> section.
27
28[ List each enhancement as a =head2 entry ]
29
30=head1 Security
fd41b2d1 31
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32XXX Any security-related notices go here. In particular, any security
33vulnerabilities closed should be noted here rather than in the
34L</Selected Bug Fixes> section.
35
36[ List each security issue as a =head2 entry ]
fd41b2d1 37
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38=head1 Incompatible Changes
39
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40XXX For a release on a stable branch, this section aspires to be:
41
42 There are no changes intentionally incompatible with 5.XXX.XXX
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43 If any exist, they are bugs, and we request that you submit a
44 report. See L</Reporting Bugs> below.
e6132dc0 45
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46[ List each incompatible change as a =head2 entry ]
47
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48=head2 Modifiable variables are no longer permitted in constants
49
50Code like:
51
52 my $var;
53 $sub = sub () { $var };
54
55where C<$var> is referenced elsewhere in some sort of modiable context
56now produces an exception when the sub is defined.
57
58This error can be avoided by adding a return to the sub definition:
59
60 $sub = sub () { return $var };
61
62This has been deprecated since perl 5.22.
63
64[perl #131138]
65
fcbec156 66=head1 Deprecations
e6132dc0 67
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68XXX Any deprecated features, syntax, modules etc. should be listed here.
69
fcbec156 70=head2 Module removals
befef368 71
74c14c97 72XXX Remove this section if not applicable.
befef368 73
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74The following modules will be removed from the core distribution in a
75future release, and will at that time need to be installed from CPAN.
76Distributions on CPAN which require these modules will need to list them as
77prerequisites.
fcbec156 78
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79The core versions of these modules will now issue C<"deprecated">-category
80warnings to alert you to this fact. To silence these deprecation warnings,
81install the modules in question from CPAN.
fcbec156 82
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83Note that these are (with rare exceptions) fine modules that you are encouraged
84to continue to use. Their disinclusion from core primarily hinges on their
85necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
86not usually on concerns over their design.
fcbec156 87
74c14c97 88=over
fcbec156 89
74c14c97 90=item XXX
fcbec156 91
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92XXX Note that deprecated modules should be listed here even if they are listed
93as an updated module in the L</Modules and Pragmata> section.
94
95=back
96
97[ List each other deprecation as a =head2 entry ]
98
99=head1 Performance Enhancements
100
101XXX Changes which enhance performance without changing behaviour go here.
102There may well be none in a stable release.
103
104[ List each enhancement as an =item entry ]
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105
106=over 4
a0348300 107
9c600b76 108=item *
a0348300 109
74c14c97 110XXX
be2eb09e 111
74c14c97 112=back
fcbec156 113
74c14c97 114=head1 Modules and Pragmata
be2eb09e 115
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116XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
117go here. If Module::CoreList is updated, generate an initial draft of the
118following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
119for important changes should then be added by hand. In an ideal world,
120dual-life modules would have a F<Changes> file that could be cribbed.
be2eb09e 121
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122The list of new and updated modules is modified automatically as part of
123preparing a Perl release, so the only reason to manually add entries here is if
124you're summarising the important changes in the module update. (Also, if the
125manually-added details don't match the automatically-generated ones, the
126release manager will have to investigate the situation carefully.)
be2eb09e 127
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128[ Within each section, list entries as an =item entry ]
129
130=head2 New Modules and Pragmata
03b7d279 131
74c14c97 132=over 4
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133
134=item *
135
74c14c97 136XXX Remove this section if not applicable.
03b7d279 137
74c14c97 138=back
03b7d279 139
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140=head2 Updated Modules and Pragmata
141
142=over 4
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143
144=item *
145
74c14c97 146L<XXX> has been upgraded from version A.xx to B.yy.
c8d86fdc 147
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148If there was something important to note about this change, include that here.
149
150=back
c8d86fdc 151
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152=head2 Removed Modules and Pragmata
153
154=over 4
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155
156=item *
157
74c14c97 158XXX
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159
160=back
161
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162=head1 Documentation
163
164XXX Changes to files in F<pod/> go here. Consider grouping entries by
165file and be sure to link to the appropriate page, e.g. L<perlfunc>.
fcbec156 166
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167=head2 New Documentation
168
169XXX Changes which create B<new> files in F<pod/> go here.
170
171=head3 L<XXX>
172
173XXX Description of the purpose of the new file here
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174
175=head2 Changes to Existing Documentation
176
177We have attempted to update the documentation to reflect the changes
178listed in this document. If you find any we have missed, send email
179to L<perlbug@perl.org|mailto:perlbug@perl.org>.
180
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181XXX Changes which significantly change existing files in F<pod/> go here.
182However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
183section.
184
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185Additionally, the following selected changes have been made:
186
74c14c97 187=head3 L<XXX>
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188
189=over 4
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190
191=item *
192
74c14c97 193XXX Description of the change here
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194
195=back
196
197=head1 Diagnostics
198
199The following additions or changes have been made to diagnostic output,
200including warnings and fatal error messages. For the complete list of
201diagnostic messages, see L<perldiag>.
202
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203XXX New or changed warnings emitted by the core's C<C> code go here. Also
204include any changes in L<perldiag> that reconcile it to the C<C> code.
205
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206=head2 New Diagnostics
207
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208XXX Newly added diagnostic messages go under here, separated into New Errors
209and New Warnings
210
211=head3 New Errors
212
213=over 4
214
215=item *
216
217XXX L<message|perldiag/"message">
218
219=back
220
221=head3 New Warnings
222
223=over 4
224
225=item *
226
227XXX L<message|perldiag/"message">
228
229=back
230
231=head2 Changes to Existing Diagnostics
232
233XXX Changes (i.e. rewording) of diagnostic messages go here
234
235=over 4
236
237=item *
238
239XXX Describe change here
240
241=back
242
243=head1 Utility Changes
244
245XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
246Most of these are built within the directory F<utils>.
247
248[ List utility changes as a =head2 entry for each utility and =item
249entries for each change
250Use L<XXX> with program names to get proper documentation linking. ]
251
252=head2 L<XXX>
253
254=over 4
255
256=item *
257
258XXX
259
260=back
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261
262=head1 Configuration and Compilation
263
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264XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
265go here. Any other changes to the Perl build process should be listed here.
266However, any platform-specific changes should be listed in the
267L</Platform Support> section, instead.
268
269[ List changes as an =item entry ].
270
fcbec156 271=over 4
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272
273=item *
274
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275Perl now no longer probes for C<d_u32align>, defaulting to C<define>
276on all platforms. This check was error prone when it was done, which
277was on 32-bit platforms only. [perl #133495]
06bfb2b1 278
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279=back
280
281=head1 Testing
282
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283XXX Any significant changes to the testing of a freshly built perl should be
284listed here. Changes which create B<new> files in F<t/> go here as do any
285large changes to the testing harness (e.g. when parallel testing was added).
286Changes to existing files in F<t/> aren't worth summarizing, although the bugs
287that they represent may be covered elsewhere.
288
289XXX If there were no significant test changes, say this:
290
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291Tests were added and changed to reflect the other additions and changes
292in this release.
293
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294XXX If instead there were significant changes, say this:
295
296Tests were added and changed to reflect the other additions and
297changes in this release. Furthermore, these significant changes were
298made:
299
300[ List each test improvement as an =item entry ]
301
302=over 4
303
304=item *
305
306XXX
307
308=back
309
dad02c36 310=head1 Platform Support
8424e368 311
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312XXX Any changes to platform support should be listed in the sections below.
313
314[ Within the sections, list each platform as an =item entry with specific
315changes as paragraphs below it. ]
316
317=head2 New Platforms
318
319XXX List any platforms that this version of perl compiles on, that previous
320versions did not. These will either be enabled by new files in the F<hints/>
321directories, or new subdirectories and F<README> files at the top level of the
322source tree.
323
324=over 4
325
326=item XXX-some-platform
327
328XXX
329
330=back
331
332=head2 Discontinued Platforms
333
334XXX List any platforms that this version of perl no longer compiles on.
fcbec156 335
fcbec156 336=over 4
061637ca 337
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338=item XXX-some-platform
339
340XXX
341
342=back
343
344=head2 Platform-Specific Notes
fcbec156 345
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346XXX List any changes for specific platforms. This could include configuration
347and compilation changes or changes in portability/compatibility. However,
348changes within modules for platforms should generally be listed in the
349L</Modules and Pragmata> section.
350
351=over 4
0076a047 352
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353=item XXX-some-platform
354
355XXX
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356
357=back
358
359=head1 Internal Changes
360
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361XXX Changes which affect the interface available to C<XS> code go here. Other
362significant internal changes for future core maintainers should be noted as
363well.
364
365[ List each change as an =item entry ]
366
fcbec156 367=over 4
061637ca 368
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369=item *
370
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371Added the C<<PL_curstackinfo->si_cxsubix>> field. This records the stack
372index of the most recently pushed sub/format/eval context. It is set and
373restored automatically by C<cx_pushsub()>, C<cx_popsub()> etc., but would
374need to be manually managed if you do any unusual manipulation of the
375context stack.
285db695 376
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377=item *
378
379Various macros dealing with character type classification and changing
380case where the input is encoded in UTF-8 now require an extra parameter
381to prevent potential reads beyond the end of the buffer. Use of these
382has generated a deprecation warning since 5.26. Details are in
383L<perldeprecation/In XS code, use of various macros dealing with UTF-8.>
384
9064626f 385=back
ed0cf058 386
9064626f 387=head1 Selected Bug Fixes
ed0cf058 388
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389XXX Important bug fixes in the core language are summarized here. Bug fixes in
390files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
391
392[ List each fix as an =item entry ]
393
9064626f 394=over 4
973ae088 395
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396=item *
397
74c14c97 398XXX
f7faf2ad 399
74c14c97 400=back
8714ff4f 401
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402=head1 Known Problems
403
404XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
405tests that had to be C<TODO>ed for the release would be noted here. Unfixed
406platform specific bugs also go here.
407
408[ List each fix as an =item entry ]
409
410=over 4
8714ff4f 411
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412=item *
413
74c14c97 414XXX
7118f704 415
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416=back
417
74c14c97 418=head1 Errata From Previous Releases
fcbec156 419
74c14c97 420=over 4
a3c77565 421
74c14c97 422=item *
fcbec156 423
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424XXX Add anything here that we forgot to add, or were mistaken about, in
425the perldelta of a previous release.
bd833cba 426
74c14c97 427=back
bd833cba 428
74c14c97 429=head1 Obituary
bd833cba 430
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431XXX If any significant core contributor or member of the CPAN community has
432died, add a short obituary here.
bd833cba 433
74c14c97 434=head1 Acknowledgements
bd833cba 435
74c14c97 436XXX Generate this with:
bd833cba 437
74c14c97 438 perl Porting/acknowledgements.pl v5.31.4..HEAD
8424e368 439
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440=head1 Reporting Bugs
441
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442If you find what you think is a bug, you might check the perl bug database
443at L<https://rt.perl.org/>. There may also be information at
71c89d21 444L<https://www.perl.org/>, the Perl Home Page.
44691e6f 445
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446If you believe you have an unreported bug, please run the L<perlbug> program
447included with your release. Be sure to trim your bug down to a tiny but
448sufficient test case. Your bug report, along with the output of C<perl -V>,
0e18d1c4 449will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
44691e6f 450
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451If the bug you are reporting has security implications which make it
452inappropriate to send to a publicly archived mailing list, then see
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453L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
454for details of how to report the issue.
44691e6f 455
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456=head1 Give Thanks
457
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458If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
459you can do so by running the C<perlthanks> program:
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460
461 perlthanks
462
463This will send an email to the Perl 5 Porters list with your show of thanks.
464
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465=head1 SEE ALSO
466
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467The F<Changes> file for an explanation of how to view exhaustive details on
468what changed.
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469
470The F<INSTALL> file for how to build Perl.
471
472The F<README> file for general stuff.
473
474The F<Artistic> and F<Copying> files for copyright information.
475
476=cut