path: root/pod/perldelta.pod

=encoding utf8

=for comment
This has been completed up to 3ea0c5818 except for:
a1da11a30dfa4f3543dcab00834ff535202f5085 (GNU/Hurd hints)

=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 v5.15.5

=head1 DESCRIPTION

This document describes differences between the 5.15.4 release and
the 5.15.5 release.

If you are upgrading from an earlier release such as 5.15.3, first read
L<perl5154delta>, which describes differences between 5.15.3 and
5.15.4.

=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</Performance Enhancements> section.

=head2 C<$[> is back

The C<$[> variable is back again, but is now implemented as a module, so
programs that do not mention it (i.e., most of them), will not incur any
run-time penalty.  It is disabled in the scope of C<use v5.16>.

XXX That last sentence is not true yet.

The new implementation has some bug fixes.  See L<arybase>.

=head1 Security

XXX Any security-related notices go here.  In particular, any security
vulnerabilities closed should be noted here rather than in the
L</Selected Bug Fixes> 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</Modules and Pragmata> section.

[ List each deprecation as a =head2 entry ]

=head2 Don't read the Unicode data base files in F<lib/unicore>

It is now deprecated to directly read the Unicode data base files.
These are stored in the F<lib/unicore> directory.  Instead, you should
use the new functions in L<Unicode::UCD>.  These provide a stable API,
and give complete information.  Perl may at some point in the future
change or remove the files.  The most likely of these files to be used
is F<lib/unicore/ToDigit.pl>.  L<Unicode::UCD/prop_invmap()> can be used
to get at its data instead.

=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 *

Due to changes in L<File::Glob>, Perl's C<glob> function and its
C<< <...> >> equivalent are now much faster.  The splitting of the pattern
into words has been rewritten in C, resulting in speed-ups of 20% in some
cases.

This does not affect VMS, as it does not use File::Glob.

=back

=head1 Modules and Pragmata

XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
go here.  If Module::CoreList is updated, generate an initial draft of the
following sections using F<Porting/corelist-perldelta.pl>, 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<Changes> file that could be
cribbed.

[ Within each section, list entries as a =item entry ]

=head2 New Modules and Pragmata

=over 4

=item *

L<arybase> -- this new module implements the C<$[> variable.

=back

=head2 Updated Modules and Pragmata

=over 4

=item *

L<Archive::Extract> has been upgraded from version 0.56 to version 0.58.

=item *

L<B::Deparse> has been upgraded from version 1.08 to 1.08.

It now correctly deparses C<CORE::do> and C<CORE::glob>.

=item *

L<CGI> has been upgraded from version 3.55 to version 3.57.

Use public and documented FCGI.pm API in CGI::Fast
CGI::Fast was using an FCGI API that was deprecated and removed from
documentation more than ten years ago. Usage of this deprecated API with
FCGI >= 0.70 or FCGI <= 0.73 introduces a security issue.
L<https://rt.cpan.org/Public/Bug/Display.html?id=68380>
L<http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2011-2766>

=item *

L<Compress::Raw::Bzip2> has been upgraded from version 2.037 to version 2.040.

=item *

L<Compress::Raw::Zlib> has been upgraded from version 2.037 to version 2.040.

=item *

L<Compress::Zlib> has been upgraded from version 2.037 to version 2.040.

=item *

L<CPANPLUS> has been upgraded from version 0.9111 to version 0.9112.

=item *

L<CPANPLUS::Dist::Build> has been upgraded from version 0.58 to version 0.60.

=item *

L<Digest::SHA> has been upgraded from version 5.62 to version 5.63.

Added code to allow very large data inputs all at once, which had previously been
limited to several hundred megabytes at a time

=item *

L<ExtUtils::MakeMaker> has been upgraded from version 6.61_01 to version 6.63_02.

=item *

L<File::Glob> has been upgrade from version 1.13 to 1.14.

It has a new C<:bsd_glob> export tag, intended to replace C<:glob>.  Like
C<:glob> it overrides C<glob> with a function that does not split the glob
pattern into words, but, unlike C<:glob>, it iterates properly in scalar
context, instead of returning the last file.

There are other changes affecting Perl's own C<glob> operator (which uses
File::Glob internally, except on VMS).  See L</Performance Enhancements>
and L</Selected Bug Fixes>.

=item *

L<HTTP::Tiny> has been upgraded from version 0.013 to version 0.016.

Adds additional shorthand methods for all common HTTP verbs,
a C<post_form()> method for POST-ing x-www-form-urlencoded data and
a C<www_form_urlencode()> utility method.

=item *

L<perlfaq> has been upgraded from version 5.0150035 to version 5.0150036.

=item *

L<Socket> as been upgraded from version 1.94_01 to 1.94_02.

It has new functions and constants for handling IPv6 sockets:

    pack_ipv6_mreq
    unpack_ipv6_mreq
    IPV6_ADD_MEMBERSHIP
    IPV6_DROP_MEMBERSHIP
    IPV6_MTU
    IPV6_MTU_DISCOVER
    IPV6_MULTICAST_HOPS
    IPV6_MULTICAST_IF
    IPV6_MULTICAST_LOOP
    IPV6_UNICAST_HOPS
    IPV6_V6ONLY

=item *

L<Unicode::Collate> has been upgraded from version 0.80 to version 0.84.

Locales updated to CLDR 2.0: mk, mt, nb, nn, ro, ru, sk, sr, sv, uk
Newly supported locales: fa, ml, mr, or, pa, si, si__dictionary,
sr_Latn, sv__reformed, ta, te, th, ur, wae.

=item *

L<Unicode::UCD> has been upgraded from version 0.36 to version 0.37.
This adds four new functions:  C<prop_aliases()>, and
C<prop_value_aliases()> which are used to find all the Unicode-approved
synonyms for property names, or to convert from one name to another;
C<prop_invlist> which returns all the code points matching a given
Unicode binary property; and C<prop_invmap> which returns the complete
specification of a given Unicode property.

=back

=head2 Removed Modules and Pragmata

=over 4

=item *

XXX

=back

=head1 Documentation

XXX Changes to files in F<pod/> go here.  Consider grouping entries by
file and be sure to link to the appropriate page, e.g. L<perlfunc>.

=head2 New Documentation

XXX Changes which create B<new> files in F<pod/> go here.

=head3 L<XXX>

XXX Description of the purpose of the new file here

=head2 Changes to Existing Documentation

XXX Changes which significantly change existing files in F<pod/> go here.
However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
section.

=head3 L<XXX>

=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<perldiag>.

XXX New or changed warnings emitted by the core's C<C> code go here. Also
include any changes in L<perldiag> that reconcile it to the C<C> code.

[ Within each section, list entries as a =item entry that links to perldiag,
  e.g.

  =item *

  L<Invalid version object|perldiag/"Invalid version object">
]

=head2 New Diagnostics

XXX Newly added diagnostic messages go here

=head3 New Errors

=over 4

=item *

XXX L<message|perldiag/"message">

=back

=head3 New Warnings

=over 4

=item *

XXX L<message|perldiag/"message">

=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<perlbug> and F<xsubpp> go
here. Most of these are built within the directories F<utils> and F<x2p>.

[ List utility changes as a =head3 entry for each utility and =item
entries for each change
Use L<XXX> with program names to get proper documentation linking. ]

=head3 L<XXX>

=over 4

=item *

XXX

=back

=head1 Configuration and Compilation

XXX Changes to F<Configure>, F<installperl>, F<installman>, 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</Platform Support> 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<new> files in F<t/> go here as do any
large changes to the testing harness (e.g. when parallel testing was added).
Changes to existing files in F<t/> 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<hints/>
directories, or new subdirectories and F<README> 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</Modules and Pragmata> section.

=over 4

=item XXX-some-platform

XXX

=back

=head1 Internal Changes

XXX Changes which affect the interface available to C<XS> 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 *

C<PL_curstash> is now reference-counted.

=back

=head1 Selected Bug Fixes

XXX Important bug fixes in the core language are summarised here.
Bug fixes in files in F<ext/> and F<lib/> are best summarised in
L</Modules and Pragmata>.

[ List each fix as a =item entry ]

=over 4

=item *

Perl now holds an extra reference count on the package that code is
currently compiling in.  This means that the following code no longer crashes [perl #101486]:

    package Foo;
    BEGIN {*Foo:: = *Bar::}
    sub foo;

=item *

F<dumpvar.pl>, and consequently the C<x> command in the debugger, have been
fixed to handle objects blessed into classes whose names contain "=".  The
contents of such objects used not to be dumped [perl #101814].

=item *

The C<x> repetition operator no longer crashes on 64-bit builds with large
repeate counts [perl #94560].

=item *

A fix to C<glob> under miniperl (used to configure modules when perl itself
is built) in Perl 5.15.3 stopped C<< <~> >> from returning the home
directory, because it cleared %ENV before calling csh.  Now C<$ENV{HOME}>
is preserved.  This fix probably does not affect anything.  If
L<File::Glob> fails to load for some reason, Perl reverts to using csh.
So it would apply in that case.

=item *

On OSes other than VMS, Perl's C<glob> operator (and the C<< <...> >> form)
use L<File::Glob> underneath.  L<File::Glob> splits the pattern into words,
before feeding each word to its C<bsd_glob> function.

There were several inconsistencies in the way the split was done.  Now
quotation marks (' and ") are always treated as shell-style word delimiters
(that allow whitespace as part of a word) and backslashes are always
preserved, unless they exist to escape quotation marks.  Before, those
would only sometimes be the case, depending on whether the pattern
contained whitespace.  Also, escaped whitespace at the end of the pattern
is no longer stripped.

=item *

C<CORE::glob> now works as a way to call the default globbing function.  It
used to respect overrides, despite the C<CORE::> prefix.

=item *

In 5.14, C</[[:lower:]]/i> and C</[[:upper:]]/i> no longer matched the
opposite case.  This has been fixed [perl #101970].

=item *

A regular expression match with an overloaded object on the right-hand side
would in some cases stringify the object too many times.

=item *

The C-level C<pregcomp> function could become confused as to whether the
pattern was in UTF8 if the pattern was an overloaded, tied, or otherwise
magical scalar [perl #101940].

=item *

A regression has been fixed that was introduced in 5.14, in C</i>
regular expression matching, in which a match improperly fails if the
pattern is in UTF-8, the target string is not, and a Latin-1 character
precedes a character in the string that should match the pattern.  [perl
#101710]

=back

=head1 Known Problems

XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
tests that had to be C<TODO>ed 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 Generate this with:

  perl Porting/acknowledgements.pl v5.15.4..HEAD

=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<perlbug>
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<perl -V>, 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<Changes> file for an explanation of how to view exhaustive details
on what changed.

The F<INSTALL> file for how to build Perl.

The F<README> file for general stuff.

The F<Artistic> and F<Copying> files for copyright information.

=cut