5 perldelta - what is new for perl v5.13.2
9 This document describes differences between the 5.13.2 release and
12 If you are upgrading from an earlier release such as 5.10, first read
13 L<perl5120delta>, which describes differences between 5.10 and
18 XXX Any important notices here
20 =head1 Incompatible Changes
22 XXX For a release on a stable branch, this section aspires to be:
24 There are no changes intentionally incompatible with 5.XXX.XXX. If any
25 exist, they are bugs and reports are welcome.
28 =head1 Core Enhancements
30 XXX New core language features go here. Summarise user-visible core language
31 enhancements. Particularly prominent performance optimisations could go
32 here, but most should go in the L</Performance Enhancements> section.
34 =head2 Non-destructive substitution
36 The substitution operator now supports a C</r> option that
37 copies the input variable, carries out the substitution on
38 the copy and returns the result. The original remains unmodified.
41 my $new = $old =~ s/cat/dog/r;
42 # $old is 'cat' and $new is 'dog'
44 This is particularly useful with C<map>. See L<perlop> for more examples.
46 =head2 package block syntax
48 A package declaration can now contain a code block, in which case the
49 declaration is in scope only inside that block. So C<package Foo { ... }>
50 is precisely equivalent to C<{ package Foo; ... }>. It also works with
51 a version number in the declaration, as in C<package Foo 1.2 { ... }>.
56 XXX List any platforms that this version of perl compiles on, that previous
57 versions did not. These will either be enabled by new files in the F<hints/>
58 directories, or new subdirectories and F<README> files at the top level of the
61 =head1 Modules and Pragmata
63 XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
64 go here. If Module::CoreList is updated, generate an initial draft of the
65 following sections using F<Porting/corelist-perldelta.pl>, which prints stub
66 entries to STDOUT. Results can be pasted in place of the '=head2' entries
67 below. A paragraph summary for important changes should then be added by hand.
68 In an ideal world, dual-life modules would have a F<Changes> file that could be
71 =head2 New Modules and Pragmata
73 =head2 Pragmata Changes
75 =head2 Updated Modules
77 =head2 Removed Modules and Pragmata
79 =head1 Utility Changes
81 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go
82 here. Most of these are built within the directories F<utils> and F<x2p>.
92 =head1 New Documentation
94 XXX Changes which create B<new> files in F<pod/> go here.
104 =head1 Changes to Existing Documentation
106 XXX Changes which significantly change existing files in F<pod/> go here.
107 Any changes to F<pod/perldiag.pod> should go in L</New or Changed Diagnostics>.
110 =head1 Performance Enhancements
112 XXX Changes which enhance performance without changing behaviour go here. There
113 may well be none in a stable release.
123 =head1 Installation and Configuration Improvements
125 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
128 =head2 Configuration improvements
132 =head2 Compilation improvements
136 =head2 Platform Specific Changes
140 =item XXX-some-platform
146 =head1 Selected Bug Fixes
148 XXX Important bug fixes in the core language are summarised here.
149 Bug fixes in files in F<ext/> and F<lib/> are best summarised in
150 L</Modules and Pragmata>.
156 Overloading now works properly in conjunction with tied variables. What
157 formerly happened was that most ops checked their arguments for overloading
158 I<before> checking for magic, so for example an overloaded object returned
159 by a tied array access would usually be treated as not overloaded
164 =head1 New or Changed Diagnostics
166 XXX New or changed warnings emitted by the core's C<C> code go here.
176 =head1 Changed Internals
178 XXX Changes which affect the interface available to C<XS> code go here.
184 The C<fund_rundefsvoffset> function has been deprecated. It appeared that
185 its design was insufficient to reliably get the lexical C<$_> at run-time.
187 Use the new C<find_rundefsv> function or the C<UNDERBAR> macro instead.
188 They directly return the right SV representing C<$_>, whether it's lexical
193 The following new functions or macros have been added to the public API:
194 C<SvNV_nomg>, C<sv_2nv_flags>, C<find_rundefsv>.
198 The C<UNDERBAR> macro now calls C<find_rundefsv>. C<dUNDERBAR> is now a
199 noop but should still be used to ensure past and future compatibility.
205 XXX Changes which create B<new> files in F<t/> go here. Changes to
206 existing files in F<t/> aren't worth summarising, although the bugs that
207 they represent may be.
217 =head1 Known Problems
219 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
220 tests that had to be C<TODO>ed for the release would be noted here, unless
221 they were specific to a particular platform (see below).
223 This is a list of some significant unfixed bugs, which are regressions
224 from either 5.XXX.XXX or 5.XXX.XXX.
236 XXX Add any new known deprecations here.
238 The following items are now deprecated.
248 =head1 Platform Specific Notes
250 XXX Any changes specific to a particular platform. VMS and Win32 are the usual
251 stars here. It's probably best to group changes under the same section layout
252 as the main perldelta
256 XXX If any significant core contributor has died, we've added a short obituary
259 =head1 Acknowledgements
261 XXX The list of people to thank goes here.
264 =head1 Reporting Bugs
266 If you find what you think is a bug, you might check the articles
267 recently posted to the comp.lang.perl.misc newsgroup and the perl
268 bug database at http://rt.perl.org/perlbug/ . There may also be
269 information at http://www.perl.org/ , the Perl Home Page.
271 If you believe you have an unreported bug, please run the B<perlbug>
272 program included with your release. Be sure to trim your bug down
273 to a tiny but sufficient test case. Your bug report, along with the
274 output of C<perl -V>, will be sent off to perlbug@perl.org to be
275 analysed by the Perl porting team.
277 If the bug you are reporting has security implications, which make it
278 inappropriate to send to a publicly archived mailing list, then please send
279 it to perl5-security-report@perl.org. This points to a closed subscription
280 unarchived mailing list, which includes all the core committers, who be able
281 to help assess the impact of issues, figure out a resolution, and help
282 co-ordinate the release of patches to mitigate or fix the problem across all
283 platforms on which Perl is supported. Please only use this address for
284 security issues in the Perl core, not for modules independently
289 The F<Changes> file for an explanation of how to view exhaustive details
292 The F<INSTALL> file for how to build Perl.
294 The F<README> file for general stuff.
296 The F<Artistic> and F<Copying> files for copyright information.