5 [ this is a template for a new perldelta file. Any text flagged as XXX needs
6 to be processed before release. ]
8 perldelta - what is new for perl v5.31.3
12 This document describes differences between the 5.31.2 release and the 5.31.3
15 If you are upgrading from an earlier release such as 5.31.1, first read
16 L<perl5312delta>, which describes differences between 5.31.1 and 5.31.2.
20 XXX Any important notices here
22 =head1 Core Enhancements
24 XXX New core language features go here. Summarize user-visible core language
25 enhancements. Particularly prominent performance optimisations could go
26 here, but most should go in the L</Performance Enhancements> section.
28 [ List each enhancement as a =head2 entry ]
32 XXX Any security-related notices go here. In particular, any security
33 vulnerabilities closed should be noted here rather than in the
34 L</Selected Bug Fixes> section.
36 [ List each security issue as a =head2 entry ]
38 =head1 Incompatible Changes
40 XXX For a release on a stable branch, this section aspires to be:
42 There are no changes intentionally incompatible with 5.XXX.XXX
43 If any exist, they are bugs, and we request that you submit a
44 report. See L</Reporting Bugs> below.
46 [ List each incompatible change as a =head2 entry ]
48 =head2 Plain "0" string now treated as a number for range operator
50 Previously a range C< "0" .. "-1" > would produce a range of numeric
51 strings from "0" through "99", this now produces an empty list, just
54 This was due to a special case that treated strings starting with "0"
55 as strings so ranges like C< "00" .. "03" > produced C< "00", "01",
56 "02", "03" >, but didn't specially handle the string C<"0">.
60 =head2 C<\K> now disallowed in look-ahead and look-behind assertions
62 This was disallowed because it causes unexpected behaviour, and no-one
63 could define what the desired behaviour was.
69 XXX Any deprecated features, syntax, modules etc. should be listed here.
71 =head2 Module removals
73 XXX Remove this section if not applicable.
75 The following modules will be removed from the core distribution in a
76 future release, and will at that time need to be installed from CPAN.
77 Distributions on CPAN which require these modules will need to list them as
80 The core versions of these modules will now issue C<"deprecated">-category
81 warnings to alert you to this fact. To silence these deprecation warnings,
82 install the modules in question from CPAN.
84 Note that these are (with rare exceptions) fine modules that you are encouraged
85 to continue to use. Their disinclusion from core primarily hinges on their
86 necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
87 not usually on concerns over their design.
93 XXX Note that deprecated modules should be listed here even if they are listed
94 as an updated module in the L</Modules and Pragmata> section.
98 [ List each other deprecation as a =head2 entry ]
100 =head1 Performance Enhancements
102 XXX Changes which enhance performance without changing behaviour go here.
103 There may well be none in a stable release.
105 [ List each enhancement as an =item entry ]
115 =head1 Modules and Pragmata
117 XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
118 go here. If Module::CoreList is updated, generate an initial draft of the
119 following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
120 for important changes should then be added by hand. In an ideal world,
121 dual-life modules would have a F<Changes> file that could be cribbed.
123 The list of new and updated modules is modified automatically as part of
124 preparing a Perl release, so the only reason to manually add entries here is if
125 you're summarising the important changes in the module update. (Also, if the
126 manually-added details don't match the automatically-generated ones, the
127 release manager will have to investigate the situation carefully.)
129 [ Within each section, list entries as an =item entry ]
131 =head2 New Modules and Pragmata
137 XXX Remove this section if not applicable.
141 =head2 Updated Modules and Pragmata
147 L<Devel::PPPort> has been upgraded from version 3.54 to 3.55.
149 The test files generated on Win32 are now identical to when they are
150 generated on POSIX-like systems.
154 L<File::Find> has been upgraded from version 1.36 to 1.37.
156 On Win32, the tests no longer require either a file in the drive root
157 directory, or a writable root directory.
161 L<Thread> has been upgraded from version 3.04 to 3.05.
165 L<Getopt::Long> has been upgraded from version 2.50 to 2.51.
169 L<Time::HiRes> has been upgraded from version 1.9761 to 1.9762.
171 Removed obsolete code such as support for pre-5.6 perl and classic
172 MacOS. [perl #134288]
176 L<I18N::LangTags> has been upgraded from version 1.07 to 1.08.
178 Document the C<IGNORE_WIN32_LOCALE> environment variable.
182 L<Test::Simple> has been upgraded from version 1.302164 to 1.302166.
186 L<XXX> has been upgraded from version A.xx to B.yy.
188 If there was something important to note about this change, include that here.
192 =head2 Removed Modules and Pragmata
204 XXX Changes to files in F<pod/> go here. Consider grouping entries by
205 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
207 =head2 New Documentation
209 XXX Changes which create B<new> files in F<pod/> go here.
213 XXX Description of the purpose of the new file here
215 =head2 Changes to Existing Documentation
217 We have attempted to update the documentation to reflect the changes
218 listed in this document. If you find any we have missed, send email
219 to L<perlbug@perl.org|mailto:perlbug@perl.org>.
221 XXX Changes which significantly change existing files in F<pod/> go here.
222 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
225 Additionally, the following selected changes have been made:
233 XXX Description of the change here
239 The following additions or changes have been made to diagnostic output,
240 including warnings and fatal error messages. For the complete list of
241 diagnostic messages, see L<perldiag>.
243 XXX New or changed warnings emitted by the core's C<C> code go here. Also
244 include any changes in L<perldiag> that reconcile it to the C<C> code.
246 =head2 New Diagnostics
248 XXX Newly added diagnostic messages go under here, separated into New Errors
257 XXX L<message|perldiag/"message">
267 XXX L<message|perldiag/"message">
271 =head2 Changes to Existing Diagnostics
273 XXX Changes (i.e. rewording) of diagnostic messages go here
279 XXX Describe change here
283 =head1 Utility Changes
285 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
286 Most of these are built within the directory F<utils>.
288 [ List utility changes as a =head2 entry for each utility and =item
289 entries for each change
290 Use L<XXX> with program names to get proper documentation linking. ]
302 =head1 Configuration and Compilation
304 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
305 go here. Any other changes to the Perl build process should be listed here.
306 However, any platform-specific changes should be listed in the
307 L</Platform Support> section, instead.
309 [ List changes as an =item entry ].
321 XXX Any significant changes to the testing of a freshly built perl should be
322 listed here. Changes which create B<new> files in F<t/> go here as do any
323 large changes to the testing harness (e.g. when parallel testing was added).
324 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
325 that they represent may be covered elsewhere.
327 XXX If there were no significant test changes, say this:
329 Tests were added and changed to reflect the other additions and changes
332 XXX If instead there were significant changes, say this:
334 Tests were added and changed to reflect the other additions and
335 changes in this release. Furthermore, these significant changes were
338 [ List each test improvement as an =item entry ]
348 =head1 Platform Support
350 XXX Any changes to platform support should be listed in the sections below.
352 [ Within the sections, list each platform as an =item entry with specific
353 changes as paragraphs below it. ]
357 XXX List any platforms that this version of perl compiles on, that previous
358 versions did not. These will either be enabled by new files in the F<hints/>
359 directories, or new subdirectories and F<README> files at the top level of the
364 =item XXX-some-platform
370 =head2 Discontinued Platforms
372 XXX List any platforms that this version of perl no longer compiles on.
376 =item XXX-some-platform
382 =head2 Platform-Specific Notes
384 XXX List any changes for specific platforms. This could include configuration
385 and compilation changes or changes in portability/compatibility. However,
386 changes within modules for platforms should generally be listed in the
387 L</Modules and Pragmata> section.
393 F<t/op/magic.t> could fail if environment varables starting with
394 C<FOO> already existed.
398 =head1 Internal Changes
400 XXX Changes which affect the interface available to C<XS> code go here. Other
401 significant internal changes for future core maintainers should be noted as
404 [ List each change as an =item entry ]
410 A new parser function L<parse_subsignature()|perlapi/parse_subsignature>
411 allows a keyword plugin to parse a subroutine signature while C<use feature
412 'signatures'> is in effect. This allows custom keywords to implement
413 semantics similar to regular C<sub> declarations that include signatures.
418 Since on some platforms we need to hold a mutex when temporarily
419 switching locales, new macros (C<STORE_LC_NUMERIC_SET_TO_NEEDED_IN>,
420 C<WITH_LC_NUMERIC_SET_TO_NEEDED> and C<WITH_LC_NUMERIC_SET_TO_NEEDED_IN>)
421 have been added to make it easier to do this safely and efficiently
422 as part of [perl #134172].
426 =head1 Selected Bug Fixes
428 XXX Important bug fixes in the core language are summarized here. Bug fixes in
429 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
431 [ List each fix as an =item entry ]
437 C<< $@ = 100; die; >> now correctly propagates the 100 as an exception
438 instead of ignoring it. [perl #134291]
442 C<< 0 0x@ >> no longer asserts in S_no_op(). [perl #134310]
446 Exceptions thrown while C<$@> is read-only could result in infinite
447 recursion as perl tried to update C<$@>, which throws another
448 exception, resulting in a stack overflow. Perl now replaces C<$@>
449 with a copy if it's not a simple writable SV. [perl #134266]
453 =head1 Known Problems
455 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
456 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
457 platform specific bugs also go here.
459 [ List each fix as an =item entry ]
469 =head1 Errata From Previous Releases
475 XXX Add anything here that we forgot to add, or were mistaken about, in
476 the perldelta of a previous release.
482 XXX If any significant core contributor or member of the CPAN community has
483 died, add a short obituary here.
485 =head1 Acknowledgements
487 XXX Generate this with:
489 perl Porting/acknowledgements.pl v5.31.2..HEAD
491 =head1 Reporting Bugs
493 If you find what you think is a bug, you might check the perl bug database
494 at L<https://rt.perl.org/>. There may also be information at
495 L<http://www.perl.org/>, the Perl Home Page.
497 If you believe you have an unreported bug, please run the L<perlbug> program
498 included with your release. Be sure to trim your bug down to a tiny but
499 sufficient test case. Your bug report, along with the output of C<perl -V>,
500 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
502 If the bug you are reporting has security implications which make it
503 inappropriate to send to a publicly archived mailing list, then see
504 L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
505 for details of how to report the issue.
509 If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
510 you can do so by running the C<perlthanks> program:
514 This will send an email to the Perl 5 Porters list with your show of thanks.
518 The F<Changes> file for an explanation of how to view exhaustive details on
521 The F<INSTALL> file for how to build Perl.
523 The F<README> file for general stuff.
525 The F<Artistic> and F<Copying> files for copyright information.