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 v5.17.9
12 This document describes differences between the 5.17.8 release and the 5.17.9
15 If you are upgrading from an earlier release such as 5.17.7, first read
16 L<perl5178delta>, which describes differences between 5.17.7 and 5.17.8.
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 ]
30 =head2 Interpolations now Accepted in Regular Expression Set Operations
32 Perl v5.17.8 introduced L<regular expression set operations|perlre/(?[ ])>.
33 They have now been expanded to allow the interpolation of a
34 previously-compiled set into a bigger set, like this:
36 my $thai_or_lao = qr/\p{Thai} + \p{Lao}/;
38 qr/(?[ \p{Digit} & $thai_or_lao ])/;
42 XXX Any security-related notices go here. In particular, any security
43 vulnerabilities closed should be noted here rather than in the
44 L</Selected Bug Fixes> section.
46 [ List each security issue as a =head2 entry ]
48 =head1 Incompatible Changes
50 XXX For a release on a stable branch, this section aspires to be:
52 There are no changes intentionally incompatible with 5.XXX.XXX
53 If any exist, they are bugs, and we request that you submit a
54 report. See L</Reporting Bugs> below.
56 [ List each incompatible change as a =head2 entry ]
60 XXX Any deprecated features, syntax, modules etc. should be listed here. In
61 particular, deprecated modules should be listed here even if they are listed as
62 an updated module in the L</Modules and Pragmata> section.
64 [ List each deprecation as a =head2 entry ]
66 =head2 Deprecated Modules
68 The following modules will be removed from the core distribution in a
69 future release, and should be installed from CPAN instead. Distributions
70 on CPAN which require these should add them to their prerequisites. The
71 core versions of these modules C<warnings> will issue a deprecation warning.
73 You can silence these deprecation warnings by installing the modules
74 in question from CPAN.
78 =item L<Archive::Extract>
82 =item L<B::Lint::Debug>
86 =item L<CPANPLUS::Backend>
88 =item L<CPANPLUS::Backend::RV>
90 =item L<CPANPLUS::Config>
92 =item L<CPANPLUS::Config::HomeEnv>
94 =item L<CPANPLUS::Configure>
96 =item C<CPANPLUS::Configure::Setup>
98 =item L<CPANPLUS::Dist>
100 =item L<CPANPLUS::Dist::Autobundle>
102 =item L<CPANPLUS::Dist::Base>
104 =item L<CPANPLUS::Dist::Build>
106 =item L<CPANPLUS::Dist::Build::Constants>
108 =item L<CPANPLUS::Dist::MM>
110 =item L<CPANPLUS::Dist::Sample>
112 =item L<CPANPLUS::Error>
114 =item L<CPANPLUS::Internals>
116 =item C<CPANPLUS::Internals::Constants>
118 =item C<CPANPLUS::Internals::Constants::Report>
120 =item L<CPANPLUS::Internals::Extract>
122 =item L<CPANPLUS::Internals::Fetch>
124 =item L<CPANPLUS::Internals::Report>
126 =item L<CPANPLUS::Internals::Search>
128 =item L<CPANPLUS::Internals::Source>
130 =item L<CPANPLUS::Internals::Source::Memory>
132 =item L<CPANPLUS::Internals::Source::SQLite>
134 =item C<CPANPLUS::Internals::Source::SQLite::Tie>
136 =item L<CPANPLUS::Internals::Utils>
138 =item C<CPANPLUS::Internals::Utils::Autoflush>
140 =item L<CPANPLUS::Module>
142 =item L<CPANPLUS::Module::Author>
144 =item L<CPANPLUS::Module::Author::Fake>
146 =item L<CPANPLUS::Module::Checksums>
148 =item L<CPANPLUS::Module::Fake>
150 =item C<CPANPLUS::Module::Signature>
152 =item L<CPANPLUS::Selfupdate>
154 =item L<CPANPLUS::Shell>
156 =item L<CPANPLUS::Shell::Classic>
158 =item L<CPANPLUS::Shell::Default>
160 =item L<CPANPLUS::Shell::Default::Plugins::CustomSource>
162 =item L<CPANPLUS::Shell::Default::Plugins::Remote>
164 =item L<CPANPLUS::Shell::Default::Plugins::Source>
166 =item L<Devel::InnerPackage>
168 =item L<Log::Message>
170 =item L<Log::Message::Config>
172 =item L<Log::Message::Handlers>
174 =item L<Log::Message::Item>
176 =item L<Log::Message::Simple>
178 =item L<Module::Pluggable>
180 =item L<Module::Pluggable::Object>
182 =item L<Object::Accessor>
186 =item L<Term::UI::History>
190 =head3 Deprecated Utilities
192 The following utilities will be removed from the core distribution in a
193 future release as their associated modules have been deprecated. They
194 will remain available with the applicable CPAN distribution.
200 Included with L<CPANPLUS>.
202 =item C<cpanp-run-perl>
204 Included with L<CPANPLUS>.
208 Included with L<CPANPLUS>.
212 The L<Pod::LaTeX> module was deprecated with 5.17.8.
216 =head2 Five additional characters should be escaped in patterns with C</x>
218 When a regular expression pattern is compiled with C</x>, Perl treats 6
219 characters as white space to ignore, such as SPACE and TAB. However,
220 Unicode recommends 11 characters be treated thusly. In preparation to
221 conforming with this in a future Perl version, in the meantime, use of
222 any of the missing characters will raise a deprecation warning, unless
223 turned off. The five characters are:
225 U+200E LEFT-TO-RIGHT MARK,
226 U+200F RIGHT-TO-LEFT MARK,
227 U+2028 LINE SEPARATOR,
229 U+2029 PARAGRAPH SEPARATOR.
231 =head1 Performance Enhancements
233 XXX Changes which enhance performance without changing behaviour go here.
234 There may well be none in a stable release.
236 [ List each enhancement as a =item entry ]
246 =head1 Modules and Pragmata
248 XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
249 go here. If Module::CoreList is updated, generate an initial draft of the
250 following sections using F<Porting/corelist-perldelta.pl>, which prints stub
251 entries to STDOUT. Results can be pasted in place of the '=head2' entries
252 below. A paragraph summary for important changes should then be added by hand.
253 In an ideal world, dual-life modules would have a F<Changes> file that could be
256 [ Within each section, list entries as a =item entry ]
258 =head2 New Modules and Pragmata
264 L<Config::Perl::V> version 0.16 has been added as a dual-lifed module.
265 It provides structured data retrieval of C<perl -V> output including
266 information only known to the C<perl> binary and not available via L<Config>.
270 =head2 Updated Modules and Pragmata
276 L<Benchmark> has been upgraded from version 1.13 to 1.14.
278 The "too few iterations" message is now a warning on STDERR
279 instead of being output on STDOUT.
283 L<Data::Dumper> has been upgraded from version 2.141 to 2.142.
285 Additional tests were added in order to improve statement, branch, condition
286 and subroutine coverage. On the basis of the coverage analysis, some of the
287 internals of Dumper.pm were refactored. Almost all methods are now
292 L<File::Temp> has been upgraded from version 0.22 to 0.22_90
294 Fixes various bugs involving directory removal. Defers unlinking tempfiles if
295 the initial unlink fails, which fixes problems on NFS.
299 L<PerlIO::scalar> has been upgraded from version 0.15 to 0.16.
301 The buffer scalar supplied may now only contain code pounts 0xFF or
302 lower. [perl #109828]
306 =head2 Removed Modules and Pragmata
318 XXX Changes to files in F<pod/> go here. Consider grouping entries by
319 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
321 =head2 New Documentation
323 XXX Changes which create B<new> files in F<pod/> go here.
327 XXX Description of the purpose of the new file here
329 =head2 Changes to Existing Documentation
331 XXX Changes which significantly change existing files in F<pod/> go here.
332 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
341 A syntax error was fixed in one of illustrative examples.
347 The following additions or changes have been made to diagnostic output,
348 including warnings and fatal error messages. For the complete list of
349 diagnostic messages, see L<perldiag>.
351 XXX New or changed warnings emitted by the core's C<C> code go here. Also
352 include any changes in L<perldiag> that reconcile it to the C<C> code.
354 =head2 New Diagnostics
356 XXX Newly added diagnostic messages go under here, separated into New Errors
365 XXX L<message|perldiag/"message">
375 Strings with code points over 0xFF may not be mapped into in-memory file handles
379 =head2 Changes to Existing Diagnostics
381 XXX Changes (i.e. rewording) of diagnostic messages go here
387 The warnings for \b{ and \B{ were added in the 5.17 series; they are a
388 deprecation warning which should be turned off by that category. One
389 should not have to turn off regular regexp warnings as well to get rid
394 =head1 Utility Changes
396 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
397 Most of these are built within the directories F<utils> and F<x2p>.
399 [ List utility changes as a =head3 entry for each utility and =item
400 entries for each change
401 Use L<XXX> with program names to get proper documentation linking. ]
409 Added C<--feature> switch which lists the first version bundle of each
414 =head1 Configuration and Compilation
416 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
417 go here. Any other changes to the Perl build process should be listed here.
418 However, any platform-specific changes should be listed in the
419 L</Platform Support> section, instead.
421 [ List changes as a =item entry ].
427 Added C<useversionedarchname> option to Configure
429 When set, it includes 'api_versionstring' in 'archname'. E.g.
430 x86_64-linux-5.13.6-thread-multi. It is unset by default.
432 This feature was requested by Tim Bunce, who observed that
433 INSTALL_BASE creates a library structure that does not
434 differentiate by perl version. Instead, it places architecture
435 specific files in "$install_base/lib/perl5/$archname". This makes
436 it difficult to use a common INSTALL_BASE library path with
437 multiple versions of perl.
439 By setting -Duseversionedarchname, the $archname will be
440 distinct for architecture *and* API version, allowing mixed use of
445 Configure will honour the external C<MAILDOMAIN> environment variable, if set.
449 Both C<META.yml> and C<META.json> files are now included in the distribution.
455 XXX Any significant changes to the testing of a freshly built perl should be
456 listed here. Changes which create B<new> files in F<t/> go here as do any
457 large changes to the testing harness (e.g. when parallel testing was added).
458 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
459 that they represent may be covered elsewhere.
461 [ List each test improvement as a =item entry ]
467 Enable perl core tests to pass when locale support is not available.
469 use L<locale> - this will now die if $Config{d_setlocale} is not true.
470 All tests that use L<locale> will skip if $Config{d_setlocale} is not true.
471 This enables us to pass tests on Android which uses ICU instead of locales.
475 =head1 Platform Support
477 XXX Any changes to platform support should be listed in the sections below.
479 [ Within the sections, list each platform as a =item entry with specific
480 changes as paragraphs below it. ]
484 XXX List any platforms that this version of perl compiles on, that previous
485 versions did not. These will either be enabled by new files in the F<hints/>
486 directories, or new subdirectories and F<README> files at the top level of the
491 =item XXX-some-platform
497 =head2 Discontinued Platforms
499 XXX List any platforms that this version of perl no longer compiles on.
503 =item XXX-some-platform
509 =head2 Platform-Specific Notes
511 XXX List any changes for specific platforms. This could include configuration
512 and compilation changes or changes in portability/compatibility. However,
513 changes within modules for platforms should generally be listed in the
514 L</Modules and Pragmata> section.
520 The character set for Extended Filename Syntax (EFS) is now enabled by default on
521 VMS. Among other things, this provides better handling of dots in directory names,
522 multiple dots in filenames,and spaces in filenames. To obtain the old behavior,
523 set the logical name C<DECC$EFS_CHARSET> to C<DISABLE>.
527 =head1 Internal Changes
529 XXX Changes which affect the interface available to C<XS> code go here. Other
530 significant internal changes for future core maintainers should be noted as
533 [ List each change as a =item entry ]
539 Synonyms for the misleadingly named C<av_len()> has been created:
540 C<av_top_index()> and C<av_tindex>. All three of these return the
541 number of the highest index in the array, not the number of elements it
542 contains. (The name C<av_top> which was introduced in Perl v.5.17.8 has
549 =head1 Selected Bug Fixes
551 XXX Important bug fixes in the core language are summarized here. Bug fixes in
552 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
554 [ List each fix as a =item entry ]
560 -DPERL_GLOBAL_STRUCT builds now free the global struct B<after>
561 they've finished using it.
565 A trailing '/' on a path in @INC will no longer have an additional '/' appended.
569 =head1 Known Problems
571 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
572 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
573 platform specific bugs also go here.
575 [ List each fix as a =item entry ]
587 XXX If any significant core contributor has died, we've added a short obituary
590 =head1 Acknowledgements
592 XXX Generate this with:
594 perl Porting/acknowledgements.pl v5.17.8..HEAD
596 =head1 Reporting Bugs
598 If you find what you think is a bug, you might check the articles recently
599 posted to the comp.lang.perl.misc newsgroup and the perl bug database at
600 http://rt.perl.org/perlbug/ . There may also be information at
601 http://www.perl.org/ , the Perl Home Page.
603 If you believe you have an unreported bug, please run the L<perlbug> program
604 included with your release. Be sure to trim your bug down to a tiny but
605 sufficient test case. Your bug report, along with the output of C<perl -V>,
606 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
608 If the bug you are reporting has security implications, which make it
609 inappropriate to send to a publicly archived mailing list, then please send it
610 to perl5-security-report@perl.org. This points to a closed subscription
611 unarchived mailing list, which includes all the core committers, who will be
612 able to help assess the impact of issues, figure out a resolution, and help
613 co-ordinate the release of patches to mitigate or fix the problem across all
614 platforms on which Perl is supported. Please only use this address for
615 security issues in the Perl core, not for modules independently distributed on
620 The F<Changes> file for an explanation of how to view exhaustive details on
623 The F<INSTALL> file for how to build Perl.
625 The F<README> file for general stuff.
627 The F<Artistic> and F<Copying> files for copyright information.