=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 v5.21.1
=head1 DESCRIPTION
=head1 Notice
-XXX Any important notices here
+This release removes a number of previously deprecated constructs, many
+that have been around for a long time. Please see L</"Incompatible Changes">
+for more information.
=head1 Core Enhancements
-XXX New core language features go here. Summarize user-visible core language
-enhancements. Particularly prominent performance optimisations could go
-here, but most should go in the L</Performance Enhancements> section.
+=head2 Unicode 7.0 is now supported
+
+For details on what is in this release, see
+L<http://www.unicode.org/versions/Unicode7.0.0/>.
+
+=head2 Experimental C Backtrace API
+
+Starting from Perl 5.21.1, on some platforms Perl supports retrieving
+the C level backtrace (similar to what symbolic debuggers like gdb do).
+
+The backtrace returns the stack trace of the C call frames,
+with the symbol names (function names), the object names (like "perl"),
+and if it can, also the source code locations (file:line).
+
+The supported platforms are Linux and OS X (some *BSD might work at
+least partly, but they have not yet been tested).
+
+The feature needs to be enabled with C<Configure -Dusecbacktrace>.
+
+Also included is a C API to retrieve backtraces.
-[ List each enhancement as a =head2 entry ]
+See L<perlhacktips/"C backtrace"> for more information.
=head2 C<qr/foo/x> now ignores any Unicode pattern white space
a subset of locale categories to be locale-aware, with the remaining
ones unaffected. See L<perllocale/The "use locale" pragma> for details.
-=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:
+=head2 C<\N{}> with a sequence of multiple spaces is now a fatal error.
- There are no changes intentionally incompatible with 5.XXX.XXX
- If any exist, they are bugs, and we request that you submit a
- report. See L</Reporting Bugs> below.
+This has been deprecated since v5.18.
=head2 In double-quotish C<\cI<X>>, I<X> must now be a printable ASCII character
'bytes' pragma causes the UTF-8 flag to not be set, just as in previous
Perl releases. This resolves [perl #112208].
-=head1 Deprecations
-
-XXX Any deprecated features, syntax, modules etc. should be listed here.
-
-=head2 Using a NO-BREAK space in a character alias for C<\N{...}> is now
-deprecated
-
-This non-graphic character is essentially indistinguishable from a
-regular space, and so should not be allowed. See
-L<charnames/CUSTOM ALIASES>.
+=head2 Support for C<?PATTERN?> without explicit operator has been removed
-=head2 Module removals
+Starting regular expressions matching only once directly with the
+question mark delimiter is now a syntax error, so that the question mark
+can be available for use in new operators. Write C<m?PATTERN?> instead,
+explicitly using the C<m> operator: the question mark delimiter still
+invokes match-once behaviour.
-XXX Remove this section if inapplicable.
+=head2 C<defined(@array)> and C<defined(%hash)> are now fatal errors
-The following modules will be removed from the core distribution in a
-future release, and will at that time need to be installed from CPAN.
-Distributions on CPAN which require these modules will need to list them as
-prerequisites.
+These have been deprecated since v5.6.1 and have raised deprecation
+warnings since v5.16.
-The core versions of these modules will now issue C<"deprecated">-category
-warnings to alert you to this fact. To silence these deprecation warnings,
-install the modules in question from CPAN.
+=head2 Using a hash or an array as a reference are now fatal errors.
-Note that these are (with rare exceptions) fine modules that you are encouraged
-to continue to use. Their disinclusion from core primarily hinges on their
-necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
-not usually on concerns over their design.
+For example, C<%foo-E<gt>{"bar"}> now causes a fatal compilation
+error. These have been deprecated since before v5.8, and have raised
+deprecation warnings since then.
-=over
+=head1 Deprecations
-=item XXX
+=head2 Using a NO-BREAK space in a character alias for C<\N{...}> is now
+deprecated
-XXX Note that deprecated modules should be listed here even if they are listed
-as an updated module in the L</Modules and Pragmata> section.
+This non-graphic character is essentially indistinguishable from a
+regular space, and so should not be allowed. See
+L<charnames/CUSTOM ALIASES>.
-=back
+=head2 A literal C<"{"> should now be escaped in a pattern
-[ List each other deprecation as a =head2 entry ]
+If you want a literal left curly bracket (also called a left brace) in a
+regular expression pattern, you should now escape it by either
+preceding it with a backslash (C<"\{">) or enclosing it within square
+brackets C<"[{]">, or by using C<\Q>; otherwise a deprecation warning
+will be raised. This was first announced as forthcoming in the v5.16
+release; it will allow future extensions to the language to happen.
=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 *
-C<av_delete> has been refactored to improve performance and reduce its memory
-footprint.
+Many internal functions have been refactored to improve performance and reduce
+their memory footprints.
L<[perl #121436]|https://rt.perl.org/Ticket/Display.html?id=121436>
+L<[perl #121906]|https://rt.perl.org/Ticket/Display.html?id=121906>
+L<[perl #121969]|https://rt.perl.org/Ticket/Display.html?id=121969>
+
+=item *
+
+C<-T> and C<-B> filetests will return sooner when an empty file is detected.
+
+L<perl #121489|https://rt.perl.org/Ticket/Display.html?id=121489>
=back
=item *
+L<Data::Dumper> has been upgraded from version 2.151 to 2.152.
+
+Changes to resolve Coverity issues.
+
+XS dumps incorrectly stored the name of code references stored in a
+GLOB.
+L<[perl #122070]|https://rt.perl.org/Ticket/Display.html?id=122070>
+
+=item *
+
L<Encode> has been upgraded from version 2.60_01 to 2.62.
B<piconv> now has better error handling when the encoding name is nonexistent,
=item *
+L<Hash::Util> has been upgraded from version 0.16 to 0.17.
+
+Minor bug fixes and documentation fixes to Hash::Util::hash_stats()
+
+=item *
+
The libnet collection of modules has been upgraded from version 1.25 to 1.27.
There are only whitespace changes to the installed files.
=item *
-L<perl5db.pl> has been upgraded from version 1.44 to 1.45.
+L<OS2::Process> has been upgraded from version 1.09 to 1.10.
=item *
-A mismatch between the documentation and the code in utf8::downgrade()
-was fixed in favour of the documentation. The optional second argument
-is now correctly treated as a perl boolean (true/false semantics) and
-not as an integer.
-
-=item *
+L<perl5db.pl> has been upgraded from version 1.44 to 1.45.
fork() in the debugger under C<tmux> will now create a new window for
the forked process. L<[perl
restores it when you restart your program with C<R> or <rerun>. L<[perl
#121509]|https://rt.perl.org/Ticket/Display.html?id=121509>
+=item *
+
+L<PerlIO::encoding> has been upgraded from version 0.18 to 0.19.
+
+No changes in behaviour.
+
+=item *
+
+L<PerlIO::mmap> has been upgraded from version 0.012 to 0.013.
+
+No changes in behaviour.
+
+=item *
+
+L<PerlIO::scalar> has been upgraded from version 0.18 to 0.19.
+
+No changes in behaviour.
+
+=item *
+
L<Unicode::Collate> has been upgraded from version 1.04 to 1.07.
Version 0.67's improved discontiguous contractions is invalidated by default
=item *
-L<Hash::Util> has been upgraded from version 0.16 to 0.17.
-
-Minor bug fixes and documentation fixes to Hash::Util::hash_stats()
-
+A mismatch between the documentation and the code in utf8::downgrade()
+was fixed in favour of the documentation. The optional second argument
+is now correctly treated as a perl boolean (true/false semantics) and
+not as an integer.
=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 Changes to Existing Documentation
+
+=head3 L<perlfunc>
-=head2 New Documentation
+=over 4
-XXX Changes which create B<new> files in F<pod/> go here.
+=item *
-=head3 L<XXX>
+C<-l> now notes that it will return false if symlinks aren't supported by the
+file system.
-XXX Description of the purpose of the new file here
+L<[perl #121523]|https://rt.perl.org/Ticket/Display.html?id=121523>
-=head2 Changes to Existing Documentation
+=item *
+
+Note that C<exec LIST> and C<system LIST> may fall back to the shell on
+Win32. Only C<exec PROGRAM LIST> and C<system PROGRAM LIST> indirect object
+syntax will reliably avoid using the shell.
+
+This has also been noted in L<perlport>.
+
+L<[perl #122046]|https://rt.perl.org/Ticket/Display.html?id=122046>
+
+=back
+
+=head3 L<perlapi>
+
+=over 4
+
+=item *
+
+Note that C<SvSetSV> doesn't do set magic.
+
+=item *
+
+C<sv_usepvn_flags> - Fix documentation to mention the use of C<NewX> instead of
+C<malloc>.
+
+L<[perl #121869]|https://rt.perl.org/Ticket/Display.html?id=121869>
+
+=item *
+
+Clarify where C<NUL> may be embedded or is required to terminate a string.
+
+=item *
+
+Previously missing documentation due to formatting errors are now included.
+
+=item *
+
+Entries are now organized into groups rather than by file where they are found.
+
+=item *
+
+Alphabetical sorting of entries is now handled by the POD generator to make
+entries easier to find when scanning.
+
+=back
+
+=head3 L<perlhacktips>
+
+=over 4
-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.
+=item *
+
+Updated documentation for the C<test.valgrind> C<make> target.
+
+L<[perl #121431]|https://rt.perl.org/Ticket/Display.html?id=121431>
+
+=back
+
+=head3 L<perlre>
+
+=over 4
-=head3 L<XXX>
+=item *
+
+The C</x> modifier has been clarified to note that comments cannot be continued
+onto the next line by escaping them.
+
+=back
+
+=head3 L<Unicode::UCD>
=over 4
=item *
-XXX Description of the change here
+The documentation includes many clarifications and fixes.
=back
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.
-
=head2 New Diagnostics
-XXX Newly added diagnostic messages go under here, separated into New Errors
-and New Warnings
-
=head3 New Errors
=over 4
=item *
-XXX L<message|perldiag/"message">
+L<In '(?...)', the '(' and '?' must be adjacent in regex; marked by S<<-- HERE> in mE<sol>%sE<sol>|perldiag/"In '(?...)', the '(' and '?' must be adjacent in regex; marked by <-- HERE in m/%s/">
+
+(F) The two-character sequence C<"(?"> in
+this context in a regular expression pattern should be an
+indivisible token, with nothing intervening between the C<"(">
+and the C<"?">, but you separated them.
+
+=item *
+
+L<In '(*VERB...)', the '(' and '*' must be adjacent in regex; marked by S<<-- HERE> in mE<sol>%sE<sol>|perldiag/"In '(*VERB...)', the '(' and '*' must be adjacent in regex; marked by <-- HERE in m/%s/">
+
+(F) The two-character sequence C<"(*"> in
+this context in a regular expression pattern should be an
+indivisible token, with nothing intervening between the C<"(">
+and the C<"*">, but you separated them.
+
+=item *
+
+L<charnames alias definitions may not contain a sequence of multiple spaces|perldiag/"charnames alias definitions may not contain a sequence of multiple spaces">
+
+(F) You defined a character name which had multiple space
+ characters in a row. Change them to single spaces. Usually these
+ names are defined in the C<:alias> import argument to C<use charnames>, but
+ they could be defined by a translator installed into C<$^H{charnames}>.
+ See L<charnames/CUSTOM ALIASES>.
+
+=item *
+
+L<charnames alias definitions may not contain trailing white-space|perldiag/"charnames alias definitions may not contain trailing white-space">
+
+(F) You defined a character name which ended in a space
+character. Remove the trailing space(s). Usually these names are
+defined in the C<:alias> import argument to C<use charnames>, but they
+could be defined by a translator installed into C<$^H{charnames}>.
+See L<charnames/CUSTOM ALIASES>.
+
+=item *
+
+L<Can't use a hash as a reference|perldiag/"Can't use a hash as a reference">
+
+(F) You tried to use a hash as a reference, as in
+C<< %foo->{"bar"} >> or C<< %$ref->{"hello"} >>. Versions of perl <= 5.6.1
+used to allow this syntax, but shouldn't have.
+
+=item *
+
+L<Can't use an array as a reference|perldiag/"Can't use an array as a reference">
+
+(F) You tried to use an array as a reference, as in
+C<< @foo->[23] >> or C<< @$ref->[99] >>. Versions of perl <= 5.6.1 used to
+allow this syntax, but shouldn't have.
+
+=item *
+
+L<Can't use 'defined(@array)' (Maybe you should just omit the defined()?)|perldiag/"Can't use 'defined(@array)' (Maybe you should just omit the defined()?)">
+
+(F) defined() is not useful on arrays because it
+checks for an undefined I<scalar> value. If you want to see if the
+array is empty, just use C<if (@array) { # not empty }> for example.
+
+=item *
+
+L<Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)|perldiag/"Can't use 'defined(%hash)' (Maybe you should just omit the defined()?)">
+
+(F) C<defined()> is not usually right on hashes.
+
+Although C<defined %hash> is false on a plain not-yet-used hash, it
+becomes true in several non-obvious circumstances, including iterators,
+weak references, stash names, even remaining true after C<undef %hash>.
+These things make C<defined %hash> fairly useless in practice, so it now
+generates a fatal error.
+
+If a check for non-empty is what you wanted then just put it in boolean
+context (see L<perldata/Scalar values>):
+
+ if (%hash) {
+ # not empty
+ }
+
+If you had C<defined %Foo::Bar::QUUX> to check whether such a package
+variable exists then that's never really been reliable, and isn't
+a good way to enquire about the features of a package, or whether
+it's loaded, etc.
+
+=item *
+
+L<Illegal suidscript|perldiag/"Illegal suidscript">
+
+(F) The script run under suidperl was somehow illegal.
=back
=item *
-L<PerlIO layer ':win32' is experimental|perldiag/"PerlIO layer ':win32' is experimental">:
+L<Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in mE<sol>%sE<sol>|perldiag/"Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/%s/">
+
+(D deprecated, regexp) You used a literal C<"{"> character in a regular
+expression pattern. You should change to use C<"\{"> instead, because a future
+version of Perl (tentatively v5.26) will consider this to be a syntax error. If
+the pattern delimiters are also braces, any matching right brace
+(C<"}">) should also be escaped to avoid confusing the parser, for
+example,
+
+ qr{abc\{def\}ghi}
+
+=item *
+
+L<NO-BREAK SPACE in a charnames alias definition is deprecated|perldiag/"NO-BREAK SPACE in a charnames alias definition is deprecated">
+
+(D deprecated) You defined a character name which contained a no-break
+space character. Change it to a regular space. Usually these names are
+defined in the C<:alias> import argument to C<use charnames>, but they
+could be defined by a translator installed into C<$^H{charnames}>. See
+L<charnames/CUSTOM ALIASES>.
+
+=item *
+
+L<PerlIO layer ':win32' is experimental|perldiag/"PerlIO layer ':win32' is experimental">
(S experimental::win32_perlio) The C<:win32> PerlIO layer is
experimental. If you want to take the risk of using this layer,
no warnings "experimental::win32_perlio";
-=back
-
-=head2 Changes to Existing Diagnostics
+=item *
-XXX Changes (i.e. rewording) of diagnostic messages go here
+L<Negative repeat count does nothing|perldiag/"Negative repeat count does nothing">
-=over 4
+(W numeric) You tried to execute the
+L<C<x>|perlop/Multiplicative Operators> repetition operator fewer than 0
+times, which doesn't make sense.
=item *
-L<Unsuccessful %s on filename containing newline|perldiag/"Unsuccessful %s on filename containing newline">
+L<localtime(%f) failed|perldiag/"localtime(%f) failed">
-This warning is now only produced when the newline is at the end of
-the filename.
+(W overflow) You called C<localtime> with a number that it could not handle:
+too large, too small, or NaN. The returned value is C<undef>.
-=back
+=item *
-=head1 Utility Changes
+L<gmtime(%f) failed|perldiag/"gmtime(%f) failed">
-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>.
+(W overflow) You called C<gmtime> with a number that it could not handle:
+too large, too small, or NaN. The returned value is C<undef>.
-[ List utility changes as a =head2 entry for each utility and =item
-entries for each change
-Use L<XXX> with program names to get proper documentation linking. ]
+=item *
-=head2 L<XXX>
+L<PerlIO layer ':win32' is experimental|perldiag/"PerlIO layer ':win32' is experimental">:
-=over 4
+(S experimental::win32_perlio) The C<:win32> PerlIO layer is
+experimental. If you want to take the risk of using this layer,
+simply disable this warning:
+
+ no warnings "experimental::win32_perlio";
=item *
-XXX
+L<Negative repeat count does nothing|perldiag/Negative repeat count does nothing>
-=back
+(W numeric) This warns when the repeat count of the
+L<C<x>|perlop/Multiplicative Operators> repetition operator is
+negative.
-=head1 Configuration and Compilation
+This warning may be changed or removed if it turn out that it was
+unwise to have added it.
-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.
+=back
-[ List changes as a =item entry ].
+=head2 Changes to Existing Diagnostics
=over 4
=item *
-XXX
+L<Variable length lookbehind not implemented in regex mE<sol>%sE<sol>|perldiag/"Variable length lookbehind not implemented in regex m/%s/">
-=back
+Information about Unicode behaviour has been added.
+
+=item *
+
+<> should be quotes
+
+This warning has been changed to
+L<< <> at require-statement should be quotes|perldiag/"<> at require-statement should be quotes" >>
+to make the issue more identifiable.
+
+=item *
+
+L<Unsuccessful %s on filename containing newline|perldiag/"Unsuccessful %s on filename containing newline">
+
+This warning is now only produced when the newline is at the end of
+the filename.
-=head1 Testing
+=back
-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 summarizing, although the bugs
-that they represent may be covered elsewhere.
+=head1 Utility Changes
-[ List each test improvement as a =item entry ]
+=head2 F<x2p/>
=over 4
=item *
-XXX
+The F<x2p/> directory has been removed from the Perl core.
+
+This removes find2perl, s2p and a2p. They have all been released to CPAN as
+separate distributions (App::find2perl, App::s2p, App::a2p).
=back
-=head1 Platform Support
+=head1 Configuration and Compilation
+
+=over 4
-XXX Any changes to platform support should be listed in the sections below.
+=item *
-[ Within the sections, list each platform as a =item entry with specific
-changes as paragraphs below it. ]
+C<make test.valgrind> now supports parallel testing.
-=head2 New Platforms
+For example:
-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.
+ TEST_JOBS=9 make test.valgrind
-=over 4
+See L<perlhacktips/valgrind> for more information.
-=item XXX-some-platform
+L<[perl #121431]|https://rt.perl.org/Ticket/Display.html?id=121431>
-XXX
+=item *
+
+The MAD (Misc Attribute Decoration) build option has been removed
+
+This was an unmaintained attempt at preserving
+the Perl parse tree more faithfully so that automatic conversion of
+Perl 5 to Perl 6 would have been easier.
+
+This build-time configuration option had been unmaintained for years,
+and had probably seriously diverged on both Perl 5 and Perl 6 sides.
=back
-=head2 Discontinued Platforms
+=head1 Platform Support
-XXX List any platforms that this version of perl no longer compiles on.
+=head2 Discontinued Platforms
=over 4
-=item XXX-some-platform
+=item NeXTSTEP/OPENSTEP
-XXX
+NeXTSTEP was proprietary OS bundled with NeXT's workstations in the early
+to mid 90's; OPENSTEP was an API specification that provided a NeXTSTEP-like
+environment on a non-NeXTSTEP system. Both are now long dead, so support
+for building Perl on them has been removed.
=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
+=item OpenBSD
-XXX
+On OpenBSD, Perl will now default to using the system C<malloc> due to the
+security features it provides. Perl's own malloc wrapper has been in use
+since v5.14 due to performance reasons, but the OpenBSD project believes
+the tradeoff is worth it and would prefer that users who need the speed
+specifically ask for it.
+
+L<[perl #122000]|https://rt.perl.org/Ticket/Display.html?id=122000>.
=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.
-
=over 4
=item *
developing v5.21. Send email to L<mailto:perl5-porters@perl.org> for
guidance.
-=back
+=item *
-=head1 Selected Bug Fixes
+A new macro L<C<isUTF8_CHAR>|perlapi/isUTF8_CHAR> has been written which
+efficiently determines if the string given by its parameters begins
+with a well-formed UTF-8 encoded character.
-XXX Important bug fixes in the core language are summarized here. Bug fixes in
-files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
+=back
-[ List each fix as a =item entry ]
+=head1 Selected Bug Fixes
=over 4
follow the standard. Perl now takes special precautions to correct for
this.
-=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. Unfixed
-platform specific bugs also go here.
-
-[ List each fix as a =item entry ]
-
-=over 4
-
=item *
-XXX
+Many issues have been detected by L<Coverity|http://www.coverity.com/> and
+fixed.
-=back
+=item *
-=head1 Errata From Previous Releases
+system() and friends should now work properly on more Android builds.
-=over 4
+Due to an oversight, the value specified through -Dtargetsh to Configure
+would end up being ignored by some of the build process. This caused perls
+cross-compiled for Android to end up with defective versions of system(),
+exec() and backticks: the commands would end up looking for C</bin/sh>
+instead of C</system/bin/sh>, and so would fail for the vast majority
+of devices, leaving C<$!> as C<ENOENT>.
=item *
-XXX Add anything here that we forgot to add, or were mistaken about, in
-the perldelta of a previous release.
+C<qr(...\(...\)...)>,
+C<qr[...\[...\]...]>,
+and
+C<qr{...\{...\}...}>
+now work. Previously it was impossible to escape these three
+left-characters with a backslash within a regular expression pattern
+where otherwise they would be considered metacharacters, and the pattern
+opening delimiter was the character, and the closing delimiter was its
+mirror character.
=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 v5.21.1..HEAD
+Perl 5.21.1 represents approximately 3 weeks of development since Perl 5.21.0
+and contains approximately 240,000 lines of changes across 680 files from 37
+authors.
+
+Excluding auto-generated files, documentation and release tools, there were
+approximately 150,000 lines of changes to 420 .pm, .t, .c and .h files.
+
+Perl continues to flourish into its third decade thanks to a vibrant community
+of users and developers. The following people are known to have contributed the
+improvements that became Perl 5.21.1:
+
+Alex Solovey, Andrew Fresh, Andy Dougherty, Brian Fraser, Chris 'BinGOs'
+Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, Daniel Dragan, Darin
+McBride, David Mitchell, Doug Bell, H.Merijn Brand, James E Keenan, Jarkko
+Hietaniemi, kafka, Karen Etheridge, Karl Williamson, Leon Timmermans, Matthew
+Horsfall, Michael Bunk, Nicholas Clark, Niels Thykier, Norman Koch, Peter John
+Acklam, Pierre Bogossian, Reini Urban, Ricardo Signes, Rob Hoelz, Shlomi Fish,
+Smylers, Steffen Müller, Steve Hay, Sullivan Beck, Thomas Sibley, Todd
+Rinaldo, Tony Cook, 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<AUTHORS> file in the Perl source distribution.
=head1 Reporting Bugs
https://perl5.git.perl.org / perl5.git / blobdiff