=encoding utf8 =head1 NAME perldelta - what is new for perl v5.29.1 =head1 DESCRIPTION This document describes differences between the 5.29.0 release and the 5.29.1 release. If you are upgrading from an earlier release such as 5.28.0, first read L, which describes differences between 5.28.0 and 5.29.0. =head1 Incompatible Changes =head2 Delimiters must now be graphemes See L =head2 Some formerly deprecated uses of an unescaped left brace C<"{"> in regular expression patterns are now illegal But to avoid breaking code unnecessarily, most instances that issued a deprecation warning, remain legal and now have a non-deprecation warning raised. See L. =head1 Performance Enhancements =over 4 =item * Translating from UTF-8 into the code point it represents now is done via a deterministic finite automaton, speeding it up. As a typical example, C now requires 12% fewer instructions than before. The performance of checking that a sequence of bytes is valid UTF-8 is similarly improved, again by using a dfa. =back =head1 Modules and Pragmata =head2 Updated Modules and Pragmata =over 4 =item * L has been upgraded from version 0.49 to 0.50. =item * L has been upgraded from version 2.074 to 2.081. =item * L has been upgraded from version 2.076 to 2.081. =item * L has been upgraded from version 0.29 to 0.30. =item * L has been upgraded from version 1.840 to 1.842. =item * L has been upgraded from version 3.40 to 3.42. =item * L has been upgraded from version 6.01 to 6.02. =item * L has been upgraded from version 0.019 to 0.020. =item * L has been upgraded from version 1.70 to 1.71. =item * L has been upgraded from version 0.2304 to 0.2308. =item * IO-Compress has been upgraded from version 2.074 to 2.081. =item * L has been upgraded from version 1.00 to 1.02. =item * L has been upgraded from version 3.56 to 3.57. =item * L has been upgraded from version 1.999811 to 1.999813. =item * L has been upgraded from version 0.5006 to 0.5007. =item * L has been upgraded from version 0.2613 to 0.2614. =item * L has been upgraded from version 5.20180626 to 5.20180720. =item * L has been upgraded from version 0.236 to 0.237. =item * L has been upgraded from version 5.021011 to 5.20180605. =item * podlators has been upgraded from version 4.10 to 4.11. =item * L has been upgraded from version 3.08 to 3.11. =item * L has been upgraded from version 1.302133 to 1.302138. =item * L has been upgraded from version 3.12 to 3.13. =item * L has been upgraded from version 1.25 to 1.28. =item * L has been upgraded from version 0.9923 to 0.9924. =back =head1 Documentation =head2 Changes to Existing Documentation We have attempted to update the documentation to reflect the changes listed in this document. If you find any we have missed, send email to L. Additionally, the following selected changes have been made: =head3 L =over 4 =item * C was wrongly listed as deprecated. This has been corrected. L<[perl #133278]|https://rt.perl.org/Ticket/Display.html?id=133278> =back =head3 L =over 4 =item * The behaviour of C when the delimiter is an apostrophe has been clarified. In particular, hyphens aren't special, and C<\x{}> isn't interpolated. L<[perl #130679]|https://rt.perl.org/Ticket/Display.html?id=130679> =back =head1 Diagnostics The following additions or changes have been made to diagnostic output, including warnings and fatal error messages. For the complete list of diagnostic messages, see L. =head2 Changes to Existing Diagnostics =over 4 =item * As noted under L above, the deprecation warning "Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by S<<-- HERE> in m/%s/" has been changed to the non-deprecation warning "Unescaped left brace in regex is passed through in regex; marked by S<<-- HERE> in m/%s/". =back =head1 Testing Tests were added and changed to reflect the other additions and changes in this release. =head1 Platform Support =head2 Platform-Specific Notes =over 4 =item HP-UX 11.11 An obscure problem in C when compiling with HP C-ANSI-C has been fixed by disabling optimizations in F. =item Windows =over 4 =item * The C build option which has long been available in F (for B) and F (for B) is now also available in F (for B). =item * The B makefile no longer defaults to Visual C++ 6.0 (a very old version which is unlikely to be widely used today). As a result, it is now a requirement to specify the C since there is no obvious choice of which modern version to default to instead. Failure to specify C will result in an error being output and the build will stop. (The B and B makefiles will automatically detect which compiler is being used, so do not require C to be set. This feature has not yet been added to the B makefile.) =back =back =head1 Selected Bug Fixes =over 4 =item * Compilation under C<-DPERL_MEM_LOG> and C<-DNO_LOCALE> have been fixed. =item * Perl 5.28 introduced an C optimization when comparing to -1 (or indirectly, e.g. >= 0). When this optimization was triggered inside a C clause it caused a warning ("Argument %s isn't numeric in smart match"). This has now been fixed. L<[perl #133368]|https://rt.perl.org/Ticket/Display.html?id=133368> =back =head1 Acknowledgements Perl 5.29.1 represents approximately 3 weeks of development since Perl 5.29.0 and contains approximately 68,000 lines of changes across 510 files from 18 authors. Excluding auto-generated files, documentation and release tools, there were approximately 62,000 lines of changes to 320 .pm, .t, .c and .h files. Perl continues to flourish into its fourth decade thanks to a vibrant community of users and developers. The following people are known to have contributed the improvements that became Perl 5.29.1: Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, Daniel Dragan, David Mitchell, François Perrad, H.Merijn Brand, Hugo van der Sanden, James E Keenan, Jerry D. Hedden, Jim Cromie, Karen Etheridge, Karl Williamson, Nicholas Clark, Sawyer X, Steve Hay, Tina Müller, Yves Orton. The list above is almost certainly incomplete as it is automatically generated from version control history. In particular, it does not include the names of the (very much appreciated) contributors who reported issues to the Perl bug tracker. Many of the changes included in this version originated in the CPAN modules included in Perl's core. We're grateful to the entire CPAN community for helping Perl to flourish. For a more complete list of all of Perl's historical contributors, please see the F file in the Perl source distribution. =head1 Reporting Bugs If you find what you think is a bug, you might check the perl bug database at L . There may also be information at L , the Perl Home Page. If you believe you have an unreported bug, please run the L program included with your release. Be sure to trim your bug down to a tiny but sufficient test case. Your bug report, along with the output of C, will be sent off to perlbug@perl.org to be analysed by the Perl porting team. If the bug you are reporting has security implications which make it inappropriate to send to a publicly archived mailing list, then see L for details of how to report the issue. =head1 Give Thanks If you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so by running the C program: perlthanks This will send an email to the Perl 5 Porters list with your show of thanks. =head1 SEE ALSO The F file for an explanation of how to view exhaustive details on what changed. The F file for how to build Perl. The F file for general stuff. The F and F files for copyright information. =cut