=encoding utf8 =head1 NAME [ this is a template for a new perldelta file. Any text flagged as XXX needs to be processed before release. ] perldelta - what is new for perl v5.15.1 =head1 DESCRIPTION This document describes differences between the 5.15.1 release and the 5.15.0 release. If you are upgrading from an earlier release such as 5.14.0, first read L, which describes differences between 5.14.0 and 5.15.0. =head1 Notice XXX Any important notices here =head1 Core Enhancements XXX New core language features go here. Summarise user-visible core language enhancements. Particularly prominent performance optimisations could go here, but most should go in the L section. [ List each enhancement as a =head2 entry ] =head2 C doesn't warn when truncating You can now limit the size of an array using C without worrying about warnings. =head2 The C<\$> prototype accepts any scalar lvalue The C<\$> and C<\[$]> subroutine prototypes now accept any scalar lvalue argument. Previously they only accepted scalars beginning with C<$> and hash and array elements. This change makes them consistent with the way the built-in C and C functions (among others) parse their arguments. This means that one can override the built-in functions with custom subroutines that parse their arguments the same way. =head2 You can now C more than one string The restriction that you can only have one C active at a time has been removed. You can now usefully C as many strings as you want (until you exhaust memory). =head1 Security XXX Any security-related notices go here. In particular, any security vulnerabilities closed should be noted here rather than in the L section. [ List each security issue as a =head2 entry ] =head1 Incompatible Changes XXX For a release on a stable branch, this section aspires to be: There are no changes intentionally incompatible with 5.XXX.XXX If any exist, they are bugs and reports are welcome. [ List each incompatible change as a =head2 entry ] =head1 Deprecations XXX Any deprecated features, syntax, modules etc. should be listed here. In particular, deprecated modules should be listed here even if they are listed as an updated module in the L section. [ List each deprecation as a =head2 entry ] =head1 Performance Enhancements XXX Changes which enhance performance without changing behaviour go here. There may well be none in a stable release. [ List each enhancement as a =item entry ] =over 4 =item * The implementation of C makes one fewer copy of the scalar's value. =item * If a studied scalar is C with a regex, the engine will now take advantage of the C data. =item * C now uses considerably less memory for shorter strings. Strings shorter than 65535 characters use roughly half the memory than previously, strings shorter than 255 characters use roughly one quarter of the memory. =back =head1 Modules and Pragmata XXX All changes to installed files in F, F, F and F go here. If Module::CoreList is updated, generate an initial draft of the following sections using F, which prints stub entries to STDOUT. Results can be pasted in place of the '=head2' entries below. A paragraph summary for important changes should then be added by hand. In an ideal world, dual-life modules would have a F file that could be cribbed. [ Within each section, list entries as a =item entry ] =head2 New Modules and Pragmata =over 4 =item * XXX =back =head2 Updated Modules and Pragmata =over 4 =item * L has been upgraded from version 2.035 to version 2.037 =item * L has been upgraded from version 2.035 to version 2.037 Added offset parameter to CRC32 =item * L has been upgraded from version 2.035 to version 2.037 IO::Compress::Zip and IO::Uncompress::Unzip now have support for LZMA (method 14). There is a fix for a CRC issue in IO::Compress::Unzip and it supports Streamed Stored context now. And fixed a Zip64 issue in IO::Compress::Zip when the content size was exactly 0xFFFFFFFF. =item * L has been upgraded from version 0.9105 to version 0.9106 =item * L has been upgraded from version 6.57_05 to version 6.58 =item * L has been upgraded from version 0.70 to version 0.72 Capturing of command output (both C and C) is now supported using L on MSWin32 without requiring L. =item * L has been upgraded from version 3.16 to version 3.17 Added Language Extension codes (langext) and Language Variation codes (langvar) as defined in the IANA language registry. Added language codes from ISO 639-5 Added language/script codes from the IANA language subtag registry Fixed an uninitialized value warning. RT 67438 Fixed the return value for the all_XXX_codes and all_XXX_names functions. RT 69100 Reorganized modules to move Locale::MODULE to Locale::Codes::MODULE to allow for cleaner future additions. The original four modules (Locale::Language, Locale::Currency, Locale::Country, Locale::Script) will continue to work, but all new sets of codes will be added in the Locale::Codes namespace. =item * L has been upgraded from version 0.14 to 0.15, as part of the lvalue attribute warnings fix. See L, below. =item * L has been upgraded from version 0.28 to version 0.29. The XS code is now compiled with C, which will aid performance under ithreads. =item * L has been upgraded from version 0.76 to version 0.77 Applied [perl #93470] silencing compiler warnings with -Wwrite-strings =item * L has been upgraded from version 0.1101 to version 0.1200 Added SetStdHandle and GetStdHandle functions =item * L has been upgraded from version 1.83 to 1.84 An unused variable was removed from the XS code. =back =head2 Removed Modules and Pragmata =over 4 =item * Perl 4-era .pl libraries Perl used to bundle a handful of library files that predate Perl 5. Most of these files, which have been deprecated since version 5.14.0, have now been removed. If your code still relies on these libraries, you can install them again from C on CPAN. =back =head1 Documentation XXX Changes to files in F go here. Consider grouping entries by file and be sure to link to the appropriate page, e.g. L. =head2 New Documentation XXX Changes which create B files in F go here. =head3 L XXX Description of the purpose of the new file here =head2 Changes to Existing Documentation XXX Changes which significantly change existing files in F go here. However, any changes to F should go in the L section. =head3 L =over 4 =item * XXX Description of the change here =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. XXX New or changed warnings emitted by the core's C code go here. Also include any changes in L that reconcile it to the C code. [ Within each section, list entries as a =item entry that links to perldiag, e.g. =item * L ] =head2 New Diagnostics XXX Newly added diagnostic messages go here =head3 New Errors =over 4 =item * XXX L =back =head3 New Warnings =over 4 =item * XXX L =back =head2 Changes to Existing Diagnostics XXX Changes (i.e. rewording) of diagnostic messages go here =over 4 =item * XXX Describe change here =back =head1 Utility Changes XXX Changes to installed programs such as F and F go here. Most of these are built within the directories F and F. [ List utility changes as a =head3 entry for each utility and =item entries for each change Use L with program names to get proper documentation linking. ] =head3 L =over 4 =item * XXX =back =head1 Configuration and Compilation XXX Changes to F, F, F, and analogous tools go here. Any other changes to the Perl build process should be listed here. However, any platform-specific changes should be listed in the L section, instead. [ List changes as a =item entry ]. =over 4 =item * XXX =back =head1 Testing XXX Any significant changes to the testing of a freshly built perl should be listed here. Changes which create B files in F go here as do any large changes to the testing harness (e.g. when parallel testing was added). Changes to existing files in F aren't worth summarising, although the bugs that they represent may be covered elsewhere. [ List each test improvement as a =item entry ] =over 4 =item * XXX =back =head1 Platform Support XXX Any changes to platform support should be listed in the sections below. [ Within the sections, list each platform as a =item entry with specific changes as paragraphs below it. ] =head2 New Platforms XXX List any platforms that this version of perl compiles on, that previous versions did not. These will either be enabled by new files in the F directories, or new subdirectories and F files at the top level of the source tree. =over 4 =item XXX-some-platform XXX =back =head2 Discontinued Platforms XXX List any platforms that this version of perl no longer compiles on. =over 4 =item XXX-some-platform XXX =back =head2 Platform-Specific Notes XXX List any changes for specific platforms. This could include configuration and compilation changes or changes in portability/compatibility. However, changes within modules for platforms should generally be listed in the L section. =over 4 =item XXX-some-platform XXX =back =head1 Internal Changes XXX Changes which affect the interface available to C code go here. Other significant internal changes for future core maintainers should be noted as well. [ List each change as a =item entry ] =over 4 =item * XXX =back =head1 Selected Bug Fixes XXX Important bug fixes in the core language are summarised here. Bug fixes in files in F and F are best summarised in L. [ List each fix as a =item entry ] =over 4 =item * Applying the :lvalue attribute to subroutine that is already defined does not work properly, as the attribute changes the way the sub is compiled. Hence, Perl 5.12 began warning when an attempt is made to apply the attribute to an already defined sub. In such cases, the attribute is discarded. But the change in 5.12 missed the case where custom attributes are also present: that case still silently and ineffectively applied the attribute. That omission has now been corrected. C (when C is already defined) now warns about the :lvalue attribute, and does not apply it. L has likewise been updated to warn and not apply the attribute. =item * =for comment Not necessary for perl5160delta The remaining discrepancies between explicit and implicit return from lvalue subroutines have been resolved. They mainly involved which error message to display when a read-only value is returned in lvalue context. Also, returning a PADTMP (the result of most built-ins, like C) in lvalue context is now forbidden for explicit return, as it always has been for implicit return. This is not a regression from 5.14, as all the cases in which it could happen where previously syntax errors. =item * =for comment Not necessary for perl5160delta Explicitly returning a tied C variable from an lvalue subroutine in list lvalue context used to clear the variable before the assignment could happen. This is something that was missed when explicit return was made to work in 5.15.0. =item * =for comment Not necessary for perl5160delta A minor memory leak, introduced in 5.15.0, has been fixed. It would occur when a hash is freed that has had its current iterator deleted [perl #93454]. =back =head1 Known Problems XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any tests that had to be Ced for the release would be noted here, unless they were specific to a particular platform (see below). This is a list of some significant unfixed bugs, which are regressions from either 5.XXX.XXX or 5.XXX.XXX. [ List each fix as a =item entry ] =over 4 =item * XXX =back =head1 Obituary XXX If any significant core contributor has died, we've added a short obituary here. =head1 Acknowledgements XXX The list of people to thank goes here. =head1 Reporting Bugs If you find what you think is a bug, you might check the articles recently posted to the comp.lang.perl.misc newsgroup and the perl bug database at http://rt.perl.org/perlbug/ . There may also be information at http://www.perl.org/ , 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 please send it to perl5-security-report@perl.org. This points to a closed subscription unarchived mailing list, which includes all the core committers, who will be able to help assess the impact of issues, figure out a resolution, and help co-ordinate the release of patches to mitigate or fix the problem across all platforms on which Perl is supported. Please only use this address for security issues in the Perl core, not for modules independently distributed on CPAN. =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