perl5120delta
(1)
Name
perl5120delta - what is new for perl v5.12.0
Synopsis
Please see following description for synopsis
Description
Perl Programmers Reference Guide PERL5120DELTA(1)
NAME
perl5120delta - what is new for perl v5.12.0
DESCRIPTION
This document describes differences between the 5.10.0
release and the 5.12.0 release.
Many of the bug fixes in 5.12.0 are already included in the
5.10.1 maintenance release.
You can see the list of those changes in the 5.10.1 release
notes (perl5101delta).
Core Enhancements
New "package NAME VERSION" syntax
This new syntax allows a module author to set the $VERSION
of a namespace when the namespace is declared with
'package'. It eliminates the need for "our $VERSION = ..."
and similar constructs. E.g.
package Foo::Bar 1.23;
# $Foo::Bar::VERSION == 1.23
There are several advantages to this:
o $VERSION is parsed in exactly the same way as "use NAME
VERSION"
o $VERSION is set at compile time
o $VERSION is a version object that provides proper
overloading of comparison operators so comparing
$VERSION to decimal (1.23) or dotted-decimal (v1.2.3)
version numbers works correctly.
o Eliminates "$VERSION = ..." and "eval $VERSION" clutter
o As it requires VERSION to be a numeric literal or
v-string literal, it can be statically parsed by
toolchain modules without "eval" the way
MM->parse_version does for "$VERSION = ..."
It does not break old code with only "package NAME", but
code that uses "package NAME VERSION" will need to be
restricted to perl 5.12.0 or newer This is analogous to the
change to "open" from two-args to three-args. Users
requiring the latest Perl will benefit, and perhaps after
several years, it will become a standard practice.
However, "package NAME VERSION" requires a new, 'strict'
version number format. See "Version number formats" for
details.
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The "..." operator
A new operator, "...", nicknamed the Yada Yada operator, has
been added. It is intended to mark placeholder code that is
not yet implemented. See "Yada Yada Operator" in perlop.
Implicit strictures
Using the "use VERSION" syntax with a version number greater
or equal to 5.11.0 will lexically enable strictures just
like "use strict" would do (in addition to enabling
features.) The following:
use 5.12.0;
means:
use strict;
use feature ':5.12';
Unicode improvements
Perl 5.12 comes with Unicode 5.2, the latest version
available to us at the time of release. This version of
Unicode was released in October 2009. See
<http://www.unicode.org/versions/Unicode5.2.0> for further
details about what's changed in this version of the
standard. See perlunicode for instructions on installing
and using other versions of Unicode.
Additionally, Perl's developers have significantly improved
Perl's Unicode implementation. For full details, see
"Unicode overhaul" below.
Y2038 compliance
Perl's core time-related functions are now Y2038 compliant.
(It may not mean much to you, but your kids will love it!)
qr overloading
It is now possible to overload the "qr//" operator, that is,
conversion to regexp, like it was already possible to
overload conversion to boolean, string or number of objects.
It is invoked when an object appears on the right hand side
of the "=~" operator or when it is interpolated into a
regexp. See overload.
Pluggable keywords
Extension modules can now cleanly hook into the Perl parser
to define new kinds of keyword-headed expression and
compound statement. The syntax following the keyword is
defined entirely by the extension. This allow a completely
non-Perl sublanguage to be parsed inline, with the correct
ops cleanly generated.
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See "PL_keyword_plugin" in perlapi for the mechanism. The
Perl core source distribution also includes a new module
XS::APItest::KeywordRPN, which implements reverse Polish
notation arithmetic via pluggable keywords. This module is
mainly used for test purposes, and is not normally
installed, but also serves as an example of how to use the
new mechanism.
Perl's developers consider this feature to be experimental.
We may remove it or change it in a backwards-incompatible
way in Perl 5.14.
APIs for more internals
The lowest layers of the lexer and parts of the pad system
now have C APIs available to XS extensions. These are
necessary to support proper use of pluggable keywords, but
have other uses too. The new APIs are experimental, and only
cover a small proportion of what would be necessary to take
full advantage of the core's facilities in these areas. It
is intended that the Perl 5.13 development cycle will see
the addition of a full range of clean, supported interfaces.
Perl's developers consider this feature to be experimental.
We may remove it or change it in a backwards-incompatible
way in Perl 5.14.
Overridable function lookup
Where an extension module hooks the creation of rv2cv ops to
modify the subroutine lookup process, this now works
correctly for bareword subroutine calls. This means that
prototypes on subroutines referenced this way will be
processed correctly. (Previously bareword subroutine names
were initially looked up, for parsing purposes, by an
unhookable mechanism, so extensions could only properly
influence subroutine names that appeared with an "&" sigil.)
A proper interface for pluggable Method Resolution Orders
As of Perl 5.12.0 there is a new interface for plugging and
using method resolution orders other than the default linear
depth first search. The C3 method resolution order added in
5.10.0 has been re-implemented as a plugin, without changing
its Perl-space interface. See perlmroapi for more
information.
"\N" experimental regex escape
Perl now supports "\N", a new regex escape which you can
think of as the inverse of "\n". It will match any character
that is not a newline, independently from the presence or
absence of the single line match modifier "/s". It is not
usable within a character class. "\N{3}" means to match 3
non-newlines; "\N{5,}" means to match at least 5.
"\N{NAME}" still means the character or sequence named
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"NAME", but "NAME" no longer can be things like 3, or "5,".
This will break a custom charnames translator which allows
numbers for character names, as "\N{3}" will now mean to
match 3 non-newline characters, and not the character whose
name is 3. (No name defined by the Unicode standard is a
number, so only custom translators might be affected.)
Perl's developers are somewhat concerned about possible user
confusion with the existing "\N{...}" construct which
matches characters by their Unicode name. Consequently, this
feature is experimental. We may remove it or change it in a
backwards-incompatible way in Perl 5.14.
DTrace support
Perl now has some support for DTrace. See "DTrace support"
in INSTALL.
Support for "configure_requires" in CPAN module metadata
Both "CPAN" and "CPANPLUS" now support the
"configure_requires" keyword in the META.yml metadata file
included in most recent CPAN distributions. This allows
distribution authors to specify configuration prerequisites
that must be installed before running Makefile.PL or
Build.PL.
See the documentation for "ExtUtils::MakeMaker" or
"Module::Build" for more on how to specify
"configure_requires" when creating a distribution for CPAN.
"each", "keys", "values" are now more flexible
The "each", "keys", "values" function can now operate on
arrays.
"when" as a statement modifier
"when" is now allowed to be used as a statement modifier.
$, flexibility
The variable $, may now be tied.
// in when clauses
// now behaves like || in when clauses
Enabling warnings from your shell environment
You can now set "-W" from the "PERL5OPT" environment
variable
"delete local"
"delete local" now allows you to locally delete a hash
entry.
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New support for Abstract namespace sockets
Abstract namespace sockets are Linux-specific socket type
that live in AF_UNIX family, slightly abusing it to be able
to use arbitrary character arrays as addresses: They start
with nul byte and are not terminated by nul byte, but with
the length passed to the socket() system call.
32-bit limit on substr arguments removed
The 32-bit limit on "substr" arguments has now been removed.
The full range of the system's signed and unsigned integers
is now available for the "pos" and "len" arguments.
Potentially Incompatible Changes
Deprecations warn by default
Over the years, Perl's developers have deprecated a number
of language features for a variety of reasons. Perl now
defaults to issuing a warning if a deprecated language
feature is used. Many of the deprecations Perl now warns you
about have been deprecated for many years. You can find a
list of what was deprecated in a given release of Perl in
the "perl5xxdelta.pod" file for that release.
To disable this feature in a given lexical scope, you should
use "no warnings 'deprecated';" For information about which
language features are deprecated and explanations of various
deprecation warnings, please see perldiag. See
"Deprecations" below for the list of features and modules
Perl's developers have deprecated as part of this release.
Version number formats
Acceptable version number formats have been formalized into
"strict" and "lax" rules. "package NAME VERSION" takes a
strict version number. "UNIVERSAL::VERSION" and the version
object constructors take lax version numbers. Providing an
invalid version will result in a fatal error. The version
argument in "use NAME VERSION" is first parsed as a numeric
literal or v-string and then passed to "UNIVERSAL::VERSION"
(and must then pass the "lax" format test).
These formats are documented fully in the version module. To
a first approximation, a "strict" version number is a
positive decimal number (integer or decimal-fraction)
without exponentiation or else a dotted-decimal v-string
with a leading 'v' character and at least three components.
A "lax" version number allows v-strings with fewer than
three components or without a leading 'v'. Under "lax"
rules, both decimal and dotted-decimal versions may have a
trailing "alpha" component separated by an underscore
character after a fractional or dotted-decimal component.
The version module adds "version::is_strict" and
"version::is_lax" functions to check a scalar against these
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rules.
@INC reorganization
In @INC, "ARCHLIB" and "PRIVLIB" now occur after after the
current version's "site_perl" and "vendor_perl". Modules
installed into "site_perl" and "vendor_perl" will now be
loaded in preference to those installed in "ARCHLIB" and
"PRIVLIB".
REGEXPs are now first class
Internally, Perl now treates compiled regular expressions
(such as those created with "qr//") as first class entities.
Perl modules which serialize, deserialize or otherwise have
deep interaction with Perl's internal data structures need
to be updated for this change. Most affected CPAN modules
have already been updated as of this writing.
Switch statement changes
The "given"/"when" switch statement handles complex
statements better than Perl 5.10.0 did (These enhancements
are also available in 5.10.1 and subsequent 5.10 releases.)
There are two new cases where "when" now interprets its
argument as a boolean, instead of an expression to be used
in a smart match:
flip-flop operators
The ".." and "..." flip-flop operators are now evaluated
in boolean context, following their usual semantics; see
"Range Operators" in perlop.
Note that, as in perl 5.10.0, "when (1..10)" will not
work to test whether a given value is an integer between
1 and 10; you should use "when ([1..10])" instead (note
the array reference).
However, contrary to 5.10.0, evaluating the flip-flop
operators in boolean context ensures it can now be
useful in a "when()", notably for implementing bistable
conditions, like in:
when (/^=begin/ .. /^=end/) {
# do something
}
defined-or operator
A compound expression involving the defined-or operator,
as in "when (expr1 // expr2)", will be treated as
boolean if the first expression is boolean. (This just
extends the existing rule that applies to the regular or
operator, as in "when (expr1 || expr2)".)
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Smart match changes
Since Perl 5.10.0, Perl's developers have made a number of
changes to the smart match operator. These, of course, also
alter the behaviour of the switch statements where smart
matching is implicitly used. These changes were also made
for the 5.10.1 release, and will remain in subsequent 5.10
releases.
Changes to type-based dispatch
The smart match operator "~~" is no longer commutative. The
behaviour of a smart match now depends primarily on the type
of its right hand argument. Moreover, its semantics have
been adjusted for greater consistency or usefulness in
several cases. While the general backwards compatibility is
maintained, several changes must be noted:
o Code references with an empty prototype are no longer
treated specially. They are passed an argument like the
other code references (even if they choose to ignore
it).
o "%hash ~~ sub {}" and "@array ~~ sub {}" now test that
the subroutine returns a true value for each key of the
hash (or element of the array), instead of passing the
whole hash or array as a reference to the subroutine.
o Due to the commutativity breakage, code references are
no longer treated specially when appearing on the left
of the "~~" operator, but like any vulgar scalar.
o "undef ~~ %hash" is always false (since "undef" can't be
a key in a hash). No implicit conversion to "" is done
(as was the case in perl 5.10.0).
o "$scalar ~~ @array" now always distributes the smart
match across the elements of the array. It's true if one
element in @array verifies "$scalar ~~ $element". This
is a generalization of the old behaviour that tested
whether the array contained the scalar.
The full dispatch table for the smart match operator is
given in "Smart matching in detail" in perlsyn.
Smart match and overloading
According to the rule of dispatch based on the rightmost
argument type, when an object overloading "~~" appears on
the right side of the operator, the overload routine will
always be called (with a 3rd argument set to a true value,
see overload.) However, when the object will appear on the
left, the overload routine will be called only when the
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rightmost argument is a simple scalar. This way,
distributivity of smart match across arrays is not broken,
as well as the other behaviours with complex types
(coderefs, hashes, regexes). Thus, writers of overloading
routines for smart match mostly need to worry only with
comparing against a scalar, and possibly with
stringification overloading; the other common cases will be
automatically handled consistently.
"~~" will now refuse to work on objects that do not overload
it (in order to avoid relying on the object's underlying
structure). (However, if the object overloads the
stringification or the numification operators, and if
overload fallback is active, it will be used instead, as
usual.)
Other potentially incompatible changes
o The definitions of a number of Unicode properties have
changed to match those of the current Unicode standard.
These are listed above under "Unicode overhaul". This
change may break code that expects the old definitions.
o The boolkeys op has moved to the group of hash ops. This
breaks binary compatibility.
o Filehandles are now always blessed into "IO::File".
The previous behaviour was to bless Filehandles into
FileHandle (an empty proxy class) if it was loaded into
memory and otherwise to bless them into "IO::Handle".
o The semantics of "use feature :5.10*" have changed
slightly. See "Modules and Pragmata" for more
information.
o Perl's developers now use git, rather than Perforce.
This should be a purely internal change only relevant to
people actively working on the core. However, you may
see minor difference in perl as a consequence of the
change. For example in some of details of the output of
"perl -V". See perlrepository for more information.
o As part of the "Test::Harness" 2.x to 3.x upgrade, the
experimental "Test::Harness::Straps" module has been
removed. See "Modules and Pragmata" for more details.
o As part of the "ExtUtils::MakeMaker" upgrade, the
"ExtUtils::MakeMaker::bytes" and
"ExtUtils::MakeMaker::vmsish" modules have been removed
from this distribution.
o "Module::CoreList" no longer contains the %:patchlevel
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hash.
o "length undef" now returns undef.
o Unsupported private C API functions are now declared
"static" to prevent leakage to Perl's public API.
o To support the bootstrapping process, miniperl no longer
builds with UTF-8 support in the regexp engine.
This allows a build to complete with PERL_UNICODE set
and a UTF-8 locale. Without this there's a
bootstrapping problem, as miniperl can't load the UTF-8
components of the regexp engine, because they're not yet
built.
o miniperl's @INC is now restricted to just "-I...", the
split of $ENV{PERL5LIB}, and "".""
o A space or a newline is now required after a "#line XXX"
directive.
o Tied filehandles now have an additional method EOF which
provides the EOF type.
o To better match all other flow control statements,
"foreach" may no longer be used as an attribute.
o Perl's command-line switch "-P", which was deprecated in
version 5.10.0, has now been removed.
Deprecations
From time to time, Perl's developers find it necessary to
deprecate features or modules we've previously shipped as
part of the core distribution. We are well aware of the pain
and frustration that a backwards-incompatible change to Perl
can cause for developers building or maintaining software in
Perl. You can be sure that when we deprecate a functionality
or syntax, it isn't a choice we make lightly. Sometimes, we
choose to deprecate functionality or syntax because it was
found to be poorly designed or implemented. Sometimes, this
is because they're holding back other features or causing
performance problems. Sometimes, the reasons are more
complex. Wherever possible, we try to keep deprecated
functionality available to developers in its previous form
for at least one major release. So long as a deprecated
feature isn't actively disrupting our ability to maintain
and extend Perl, we'll try to leave it in place as long as
possible.
The following items are now deprecated:
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suidperl
"suidperl" is no longer part of Perl. It used to provide
a mechanism to emulate setuid permission bits on systems
that don't support it properly.
Use of ":=" to mean an empty attribute list
An accident of Perl's parser meant that these
constructions were all equivalent:
my $pi := 4;
my $pi : = 4;
my $pi : = 4;
with the ":" being treated as the start of an attribute
list, which ends before the "=". As whitespace is not
significant here, all are parsed as an empty attribute
list, hence all the above are equivalent to, and better
written as
my $pi = 4;
because no attribute processing is done for an empty
list.
As is, this meant that ":=" cannot be used as a new
token, without silently changing the meaning of existing
code. Hence that particular form is now deprecated, and
will become a syntax error. If it is absolutely
necessary to have empty attribute lists (for example,
because of a code generator) then avoid the warning by
adding a space before the "=".
"UNIVERSAL->import()"
The method "UNIVERSAL->import()" is now deprecated.
Attempting to pass import arguments to a "use UNIVERSAL"
statement will result in a deprecation warning.
Use of "goto" to jump into a construct
Using "goto" to jump from an outer scope into an inner
scope is now deprecated. This rare use case was causing
problems in the implementation of scopes.
Custom character names in \N{name} that don't look like
names
In "\N{name}", name can be just about anything. The
standard Unicode names have a very limited domain, but a
custom name translator could create names that are, for
example, made up entirely of punctuation symbols. It is
now deprecated to make names that don't begin with an
alphabetic character, and aren't alphanumeric or contain
other than a very few other characters, namely spaces,
dashes, parentheses and colons. Because of the added
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meaning of "\N" (See ""\N" experimental regex escape"),
names that look like curly brace -enclosed quantifiers
won't work. For example, "\N{3,4}" now means to match 3
to 4 non-newlines; before a custom name "3,4" could have
been created.
Deprecated Modules
The following modules will be removed from the core
distribution in a future release, and should be
installed from CPAN instead. Distributions on CPAN which
require these should add them to their prerequisites.
The core versions of these modules warnings will issue a
deprecation warning.
If you ship a packaged version of Perl, either alone or
as part of a larger system, then you should carefully
consider the reprecussions of core module deprecations.
You may want to consider shipping your default build of
Perl with packages for some or all deprecated modules
which install into "vendor" or "site" perl library
directories. This will inhibit the deprecation warnings.
Alternatively, you may want to consider patching
lib/deprecate.pm to provide deprecation warnings
specific to your packaging system or distribution of
Perl, consistent with how your packaging system or
distribution manages a staged transition from a release
where the installation of a single package provides the
given functionality, to a later release where the system
administrator needs to know to install multiple packages
to get that same functionality.
You can silence these deprecation warnings by installing
the modules in question from CPAN. To install the
latest version of all of them, just install
"Task::Deprecations::5_12".
Class::ISA
Pod::Plainer
Shell
Switch
Switch is buggy and should be avoided. You may find
Perl's new "given"/"when" feature a suitable
replacement. See "Switch statements" in perlsyn for
more information.
Assignment to $[
Use of the attribute :locked on subroutines
Use of "locked" with the attributes pragma
Use of "unique" with the attributes pragma
Perl_pmflag
"Perl_pmflag" is no longer part of Perl's public API.
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Calling it now generates a deprecation warning, and it
will be removed in a future release. Although listed as
part of the API, it was never documented, and only ever
used in toke.c, and prior to 5.10, regcomp.c. In core,
it has been replaced by a static function.
Numerous Perl 4-era libraries
termcap.pl, tainted.pl, stat.pl, shellwords.pl, pwd.pl,
open3.pl, open2.pl, newgetopt.pl, look.pl, find.pl,
finddepth.pl, importenv.pl, hostname.pl, getopts.pl,
getopt.pl, getcwd.pl, flush.pl, fastcwd.pl,
exceptions.pl, ctime.pl, complete.pl, cacheout.pl,
bigrat.pl, bigint.pl, bigfloat.pl, assert.pl, abbrev.pl,
dotsh.pl, and timelocal.pl are all now deprecated.
Earlier, Perl's developers intended to remove these
libraries from Perl's core for the 5.14.0 release.
During final testing before the release of 5.12.0,
several developers discovered current production code
using these ancient libraries, some inside the Perl core
itself. Accordingly, the pumpking granted them a stay
of execution. They will begin to warn about their
deprecation in the 5.14.0 release and will be removed in
the 5.16.0 release.
Unicode overhaul
Perl's developers have made a concerted effort to update
Perl to be in sync with the latest Unicode standard. Changes
for this include:
Perl can now handle every Unicode character property. New
documentation, perluniprops, lists all available non-Unihan
character properties. By default, perl does not expose
Unihan, deprecated or Unicode-internal properties. See
below for more details on these; there is also a section in
the pod listing them, and explaining why they are not
exposed.
Perl now fully supports the Unicode compound-style of using
"=" and ":" in writing regular expressions:
"\p{property=value}" and "\p{property:value}" (both of which
mean the same thing).
Perl now fully supports the Unicode loose matching rules for
text between the braces in "\p{...}" constructs. In
addition, Perl allows underscores between digits of numbers.
Perl now accepts all the Unicode-defined synonyms for
properties and property values.
"qr/\X/", which matches a Unicode logical character, has
been expanded to work better with various Asian languages.
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It now is defined as an extended grapheme cluster. (See
<http://www.unicode.org/reports/tr29/>). Anything matched
previously and that made sense will continue to be accepted.
Additionally:
o "\X" will not break apart a "CR LF" sequence.
o "\X" will now match a sequence which includes the "ZWJ"
and "ZWNJ" characters.
o "\X" will now always match at least one character,
including an initial mark. Marks generally come after a
base character, but it is possible in Unicode to have
them in isolation, and "\X" will now handle that case,
for example at the beginning of a line, or after a
"ZWSP". And this is the part where "\X" doesn't match
the things that it used to that don't make sense.
Formerly, for example, you could have the nonsensical
case of an accented LF.
o "\X" will now match a (Korean) Hangul syllable sequence,
and the Thai and Lao exception cases.
Otherwise, this change should be transparent for the non-
affected languages.
"\p{...}" matches using the Canonical_Combining_Class
property were completely broken in previous releases of
Perl. They should now work correctly.
Before Perl 5.12, the Unicode "Decomposition_Type=Compat"
property and a Perl extension had the same name, which led
to neither matching all the correct values (with more than
100 mistakes in one, and several thousand in the other). The
Perl extension has now been renamed to be
"Decomposition_Type=Noncanonical" (short: "dt=noncanon"). It
has the same meaning as was previously intended, namely the
union of all the non-canonical Decomposition types, with
Unicode "Compat" being just one of those.
"\p{Decomposition_Type=Canonical}" now includes the Hangul
syllables.
"\p{Uppercase}" and "\p{Lowercase}" now work as the Unicode
standard says they should. This means they each match a few
more characters than they used to.
"\p{Cntrl}" now matches the same characters as
"\p{Control}". This means it no longer will match Private
Use (gc=co), Surrogates (gc=cs), nor Format (gc=cf) code
points. The Format code points represent the biggest
possible problem. All but 36 of them are either officially
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deprecated or strongly discouraged from being used. Of those
36, likely the most widely used are the soft hyphen
(U+00AD), and BOM, ZWSP, ZWNJ, WJ, and similar characters,
plus bidirectional controls.
"\p{Alpha}" now matches the same characters as
"\p{Alphabetic}". Before 5.12, Perl's definition definition
included a number of things that aren't really alpha (all
marks) while omitting many that were. The definitions of
"\p{Alnum}" and "\p{Word}" depend on Alpha's definition and
have changed accordingly.
"\p{Word}" no longer incorrectly matches non-word characters
such as fractions.
"\p{Print}" no longer matches the line control characters:
Tab, LF, CR, FF, VT, and NEL. This brings it in line with
standards and the documentation.
"\p{XDigit}" now matches the same characters as
"\p{Hex_Digit}". This means that in addition to the
characters it currently matches, "[A-Fa-f0-9]", it will also
match the 22 fullwidth equivalents, for example U+FF10:
FULLWIDTH DIGIT ZERO.
The Numeric type property has been extended to include the
Unihan characters.
There is a new Perl extension, the 'Present_In', or simply
'In', property. This is an extension of the Unicode Age
property, but "\p{In=5.0}" matches any code point whose
usage has been determined as of Unicode version 5.0. The
"\p{Age=5.0}" only matches code points added in precisely
version 5.0.
A number of properties now have the correct values for
unassigned code points. The affected properties are
Bidi_Class, East_Asian_Width, Joining_Type,
Decomposition_Type, Hangul_Syllable_Type, Numeric_Type, and
Line_Break.
The Default_Ignorable_Code_Point, ID_Continue, and ID_Start
properties are now up to date with current Unicode
definitions.
Earlier versions of Perl erroneously exposed certain
properties that are supposed to be Unicode internal-only.
Use of these in regular expressions will now generate, if
enabled, a deprecation warning message. The properties are:
Other_Alphabetic, Other_Default_Ignorable_Code_Point,
Other_Grapheme_Extend, Other_ID_Continue, Other_ID_Start,
Other_Lowercase, Other_Math, and Other_Uppercase.
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It is now possible to change which Unicode properties Perl
understands on a per-installation basis. As mentioned above,
certain properties are turned off by default. These include
all the Unihan properties (which should be accessible via
the CPAN module Unicode::Unihan) and any deprecated or
Unicode internal-only property that Perl has never exposed.
The generated files in the "lib/unicore/To" directory are
now more clearly marked as being stable, directly usable by
applications. New hash entries in them give the format of
the normal entries, which allows for easier machine parsing.
Perl can generate files in this directory for any property,
though most are suppressed. You can find instructions for
changing which are written in perluniprops.
Modules and Pragmata
New Modules and Pragmata
"autodie"
"autodie" is a new lexically-scoped alternative for the
"Fatal" module. The bundled version is 2.06_01. Note
that in this release, using a string eval when "autodie"
is in effect can cause the autodie behaviour to leak
into the surrounding scope. See "BUGS" in autodie for
more details.
Version 2.06_01 has been added to the Perl core.
"Compress::Raw::Bzip2"
Version 2.024 has been added to the Perl core.
"overloading"
"overloading" allows you to lexically disable or enable
overloading for some or all operations.
Version 0.001 has been added to the Perl core.
"parent"
"parent" establishes an ISA relationship with base
classes at compile time. It provides the key feature of
"base" without further unwanted behaviors.
Version 0.223 has been added to the Perl core.
"Parse::CPAN::Meta"
Version 1.40 has been added to the Perl core.
"VMS::DCLsym"
Version 1.03 has been added to the Perl core.
"VMS::Stdio"
Version 2.4 has been added to the Perl core.
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"XS::APItest::KeywordRPN"
Version 0.003 has been added to the Perl core.
Updated Pragmata
"base"
Upgraded from version 2.13 to 2.15.
"bignum"
Upgraded from version 0.22 to 0.23.
"charnames"
"charnames" now contains the Unicode NameAliases.txt
database file. This has the effect of adding some extra
"\N" character names that formerly wouldn't have been
recognised; for example, "\N{LATIN CAPITAL LETTER GHA}".
Upgraded from version 1.06 to 1.07.
"constant"
Upgraded from version 1.13 to 1.20.
"diagnostics"
"diagnostics" now supports %.0f formatting internally.
"diagnostics" no longer suppresses "Use of uninitialized
value in range (or flip)" warnings. [perl #71204]
Upgraded from version 1.17 to 1.19.
"feature"
In "feature", the meaning of the ":5.10" and ":5.10.X"
feature bundles has changed slightly. The last
component, if any (i.e. "X") is simply ignored. This is
predicated on the assumption that new features will not,
in general, be added to maintenance releases. So ":5.10"
and ":5.10.X" have identical effect. This is a change to
the behaviour documented for 5.10.0.
"feature" now includes the "unicode_strings" feature:
use feature "unicode_strings";
This pragma turns on Unicode semantics for the case-
changing operations ("uc", "lc", "ucfirst", "lcfirst")
on strings that don't have the internal UTF-8 flag set,
but that contain single-byte characters between 128 and
255.
Upgraded from version 1.11 to 1.16.
"less"
"less" now includes the "stash_name" method to allow
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subclasses of "less" to pick where in %^H to store their
stash.
Upgraded from version 0.02 to 0.03.
"lib"
Upgraded from version 0.5565 to 0.62.
"mro"
"mro" is now implemented as an XS extension. The
documented interface has not changed. Code relying on
the implementation detail that some "mro::" methods
happened to be available at all times gets to "keep both
pieces".
Upgraded from version 1.00 to 1.02.
"overload"
"overload" now allow overloading of 'qr'.
Upgraded from version 1.06 to 1.10.
"threads"
Upgraded from version 1.67 to 1.75.
"threads::shared"
Upgraded from version 1.14 to 1.32.
"version"
"version" now has support for "Version number formats"
as described earlier in this document and in its own
documentation.
Upgraded from version 0.74 to 0.82.
"warnings"
"warnings" has a new "warnings::fatal_enabled()"
function. It also includes a new "illegalproto" warning
category. See also "New or Changed Diagnostics" for this
change.
Upgraded from version 1.06 to 1.09.
Updated Modules
"Archive::Extract"
Upgraded from version 0.24 to 0.38.
"Archive::Tar"
Upgraded from version 1.38 to 1.54.
"Attribute::Handlers"
Upgraded from version 0.79 to 0.87.
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"AutoLoader"
Upgraded from version 5.63 to 5.70.
"B::Concise"
Upgraded from version 0.74 to 0.78.
"B::Debug"
Upgraded from version 1.05 to 1.12.
"B::Deparse"
Upgraded from version 0.83 to 0.96.
"B::Lint"
Upgraded from version 1.09 to 1.11_01.
"CGI"
Upgraded from version 3.29 to 3.48.
"Class::ISA"
Upgraded from version 0.33 to 0.36.
NOTE: "Class::ISA" is deprecated and may be removed from
a future version of Perl.
"Compress::Raw::Zlib"
Upgraded from version 2.008 to 2.024.
"CPAN"
Upgraded from version 1.9205 to 1.94_56.
"CPANPLUS"
Upgraded from version 0.84 to 0.90.
"CPANPLUS::Dist::Build"
Upgraded from version 0.06_02 to 0.46.
"Data::Dumper"
Upgraded from version 2.121_14 to 2.125.
"DB_File"
Upgraded from version 1.816_1 to 1.820.
"Devel::PPPort"
Upgraded from version 3.13 to 3.19.
"Digest"
Upgraded from version 1.15 to 1.16.
"Digest::MD5"
Upgraded from version 2.36_01 to 2.39.
"Digest::SHA"
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Upgraded from version 5.45 to 5.47.
"Encode"
Upgraded from version 2.23 to 2.39.
"Exporter"
Upgraded from version 5.62 to 5.64_01.
"ExtUtils::CBuilder"
Upgraded from version 0.21 to 0.27.
"ExtUtils::Command"
Upgraded from version 1.13 to 1.16.
"ExtUtils::Constant"
Upgraded from version 0.2 to 0.22.
"ExtUtils::Install"
Upgraded from version 1.44 to 1.55.
"ExtUtils::MakeMaker"
Upgraded from version 6.42 to 6.56.
"ExtUtils::Manifest"
Upgraded from version 1.51_01 to 1.57.
"ExtUtils::ParseXS"
Upgraded from version 2.18_02 to 2.21.
"File::Fetch"
Upgraded from version 0.14 to 0.24.
"File::Path"
Upgraded from version 2.04 to 2.08_01.
"File::Temp"
Upgraded from version 0.18 to 0.22.
"Filter::Simple"
Upgraded from version 0.82 to 0.84.
"Filter::Util::Call"
Upgraded from version 1.07 to 1.08.
"Getopt::Long"
Upgraded from version 2.37 to 2.38.
"IO"
Upgraded from version 1.23_01 to 1.25_02.
"IO::Zlib"
Upgraded from version 1.07 to 1.10.
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"IPC::Cmd"
Upgraded from version 0.40_1 to 0.54.
"IPC::SysV"
Upgraded from version 1.05 to 2.01.
"Locale::Maketext"
Upgraded from version 1.12 to 1.14.
"Locale::Maketext::Simple"
Upgraded from version 0.18 to 0.21.
"Log::Message"
Upgraded from version 0.01 to 0.02.
"Log::Message::Simple"
Upgraded from version 0.04 to 0.06.
"Math::BigInt"
Upgraded from version 1.88 to 1.89_01.
"Math::BigInt::FastCalc"
Upgraded from version 0.16 to 0.19.
"Math::BigRat"
Upgraded from version 0.21 to 0.24.
"Math::Complex"
Upgraded from version 1.37 to 1.56.
"Memoize"
Upgraded from version 1.01_02 to 1.01_03.
"MIME::Base64"
Upgraded from version 3.07_01 to 3.08.
"Module::Build"
Upgraded from version 0.2808_01 to 0.3603.
"Module::CoreList"
Upgraded from version 2.12 to 2.29.
"Module::Load"
Upgraded from version 0.12 to 0.16.
"Module::Load::Conditional"
Upgraded from version 0.22 to 0.34.
"Module::Loaded"
Upgraded from version 0.01 to 0.06.
"Module::Pluggable"
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Upgraded from version 3.6 to 3.9.
"Net::Ping"
Upgraded from version 2.33 to 2.36.
"NEXT"
Upgraded from version 0.60_01 to 0.64.
"Object::Accessor"
Upgraded from version 0.32 to 0.36.
"Package::Constants"
Upgraded from version 0.01 to 0.02.
"PerlIO"
Upgraded from version 1.04 to 1.06.
"Pod::Parser"
Upgraded from version 1.35 to 1.37.
"Pod::Perldoc"
Upgraded from version 3.14_02 to 3.15_02.
"Pod::Plainer"
Upgraded from version 0.01 to 1.02.
NOTE: "Pod::Plainer" is deprecated and may be removed
from a future version of Perl.
"Pod::Simple"
Upgraded from version 3.05 to 3.13.
"Safe"
Upgraded from version 2.12 to 2.22.
"SelfLoader"
Upgraded from version 1.11 to 1.17.
"Storable"
Upgraded from version 2.18 to 2.22.
"Switch"
Upgraded from version 2.13 to 2.16.
NOTE: "Switch" is deprecated and may be removed from a
future version of Perl.
"Sys::Syslog"
Upgraded from version 0.22 to 0.27.
"Term::ANSIColor"
Upgraded from version 1.12 to 2.02.
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"Term::UI"
Upgraded from version 0.18 to 0.20.
"Test"
Upgraded from version 1.25 to 1.25_02.
"Test::Harness"
Upgraded from version 2.64 to 3.17.
"Test::Simple"
Upgraded from version 0.72 to 0.94.
"Text::Balanced"
Upgraded from version 2.0.0 to 2.02.
"Text::ParseWords"
Upgraded from version 3.26 to 3.27.
"Text::Soundex"
Upgraded from version 3.03 to 3.03_01.
"Thread::Queue"
Upgraded from version 2.00 to 2.11.
"Thread::Semaphore"
Upgraded from version 2.01 to 2.09.
"Tie::RefHash"
Upgraded from version 1.37 to 1.38.
"Time::HiRes"
Upgraded from version 1.9711 to 1.9719.
"Time::Local"
Upgraded from version 1.18 to 1.1901_01.
"Time::Piece"
Upgraded from version 1.12 to 1.15.
"Unicode::Collate"
Upgraded from version 0.52 to 0.52_01.
"Unicode::Normalize"
Upgraded from version 1.02 to 1.03.
"Win32"
Upgraded from version 0.34 to 0.39.
"Win32API::File"
Upgraded from version 0.1001_01 to 0.1101.
"XSLoader"
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Upgraded from version 0.08 to 0.10.
Removed Modules and Pragmata
"attrs"
Removed from the Perl core. Prior version was 1.02.
"CPAN::API::HOWTO"
Removed from the Perl core. Prior version was 'undef'.
"CPAN::DeferedCode"
Removed from the Perl core. Prior version was 5.50.
"CPANPLUS::inc"
Removed from the Perl core. Prior version was 'undef'.
"DCLsym"
Removed from the Perl core. Prior version was 1.03.
"ExtUtils::MakeMaker::bytes"
Removed from the Perl core. Prior version was 6.42.
"ExtUtils::MakeMaker::vmsish"
Removed from the Perl core. Prior version was 6.42.
"Stdio"
Removed from the Perl core. Prior version was 2.3.
"Test::Harness::Assert"
Removed from the Perl core. Prior version was 0.02.
"Test::Harness::Iterator"
Removed from the Perl core. Prior version was 0.02.
"Test::Harness::Point"
Removed from the Perl core. Prior version was 0.01.
"Test::Harness::Results"
Removed from the Perl core. Prior version was 0.01.
"Test::Harness::Straps"
Removed from the Perl core. Prior version was 0.26_01.
"Test::Harness::Util"
Removed from the Perl core. Prior version was 0.01.
"XSSymSet"
Removed from the Perl core. Prior version was 1.1.
Deprecated Modules and Pragmata
See "Deprecated Modules" above.
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Documentation
New Documentation
o perlhaiku contains instructions on how to build perl for
the Haiku platform.
o perlmroapi describes the new interface for pluggable
Method Resolution Orders.
o perlperf, by Richard Foley, provides an introduction to
the use of performance and optimization techniques which
can be used with particular reference to perl programs.
o perlrepository describes how to access the perl source
using the git version control system.
o perlpolicy extends the "Social contract about
contributed modules" into the beginnings of a document
on Perl porting policies.
Changes to Existing Documentation
o The various large Changes* files (which listed every
change made to perl over the last 18 years) have been
removed, and replaced by a small file, also called
Changes, which just explains how that same information
may be extracted from the git version control system.
o Porting/patching.pod has been deleted, as it mainly
described interacting with the old Perforce-based
repository, which is now obsolete. Information still
relevant has been moved to perlrepository.
o The syntax "unless (EXPR) BLOCK else BLOCK" is now
documented as valid, as is the syntax "unless (EXPR)
BLOCK elsif (EXPR) BLOCK ... else BLOCK", although
actually using the latter may not be the best idea for
the readability of your source code.
o Documented -X overloading.
o Documented that "when()" treats specially most of the
filetest operators
o Documented "when" as a syntax modifier.
o Eliminated "Old Perl threads tutorial", which described
5005 threads.
pod/perlthrtut.pod is the same material reworked for
ithreads.
o Correct previous documentation: v-strings are not
deprecated
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With version objects, we need them to use MODULE VERSION
syntax. This patch removes the deprecation notice.
o Security contact information is now part of perlsec.
o A significant fraction of the core documentation has
been updated to clarify the behavior of Perl's Unicode
handling.
Much of the remaining core documentation has been
reviewed and edited for clarity, consistent use of
language, and to fix the spelling of Tom Christiansen's
name.
o The Pod specification (perlpodspec) has been updated to
bring the specification in line with modern usage
already supported by most Pod systems. A parameter
string may now follow the format name in a "begin/end"
region. Links to URIs with a text description are now
allowed. The usage of "L<"section">" has been marked as
deprecated.
o if.pm has been documented in "use" in perlfunc as a
means to get conditional loading of modules despite the
implicit BEGIN block around "use".
o The documentation for $1 in perlvar.pod has been
clarified.
o "\N{U+wide hex char}" is now documented.
Selected Performance Enhancements
o A new internal cache means that "isa()" will often be
faster.
o The implementation of "C3" Method Resolution Order has
been optimised - linearisation for classes with single
inheritance is 40% faster. Performance for multiple
inheritance is unchanged.
o Under "use locale", the locale-relevant information is
now cached on read-only values, such as the list
returned by "keys %hash". This makes operations such as
"sort keys %hash" in the scope of "use locale" much
faster.
o Empty "DESTROY" methods are no longer called.
o "Perl_sv_utf8_upgrade()" is now faster.
o "keys" on empty hash is now faster.
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o "if (%foo)" has been optimized to be faster than "if
(keys %foo)".
o The string repetition operator ("$str x $num") is now
several times faster when $str has length one or $num is
large.
o Reversing an array to itself (as in "@a = reverse @a")
in void context now happens in-place and is several
orders of magnitude faster than it used to be. It will
also preserve non-existent elements whenever possible,
i.e. for non magical arrays or tied arrays with "EXISTS"
and "DELETE" methods.
Installation and Configuration Improvements
o perlapi, perlintern, perlmodlib and perltoc are now all
generated at build time, rather than being shipped as
part of the release.
o If "vendorlib" and "vendorarch" are the same, then they
are only added to @INC once.
o $Config{usedevel} and the C-level "PERL_USE_DEVEL" are
now defined if perl is built with "-Dusedevel".
o Configure will enable use of "-fstack-protector", to
provide protection against stack-smashing attacks, if
the compiler supports it.
o Configure will now determine the correct prototypes for
re-entrant functions and for "gconvert" if you are using
a C++ compiler rather than a C compiler.
o On Unix, if you build from a tree containing a git
repository, the configuration process will note the
commit hash you have checked out, for display in the
output of "perl -v" and "perl -V". Unpushed local
commits are automatically added to the list of local
patches displayed by "perl -V".
o Perl now supports SystemTap's "dtrace" compatibility
layer and an issue with linking "miniperl" has been
fixed in the process.
o perldoc now uses "less -R" instead of "less" for
improved behaviour in the face of "groff"'s new usage of
ANSI escape codes.
o "perl -V" now reports use of the compile-time options
"USE_PERL_ATOF" and "USE_ATTRIBUTES_FOR_PERLIO".
o As part of the flattening of ext, all extensions on all
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platforms are built by make_ext.pl. This replaces the
Unix-specific ext/util/make_ext, VMS-specific
make_ext.com and Win32-specific win32/buildext.pl.
Internal Changes
Each release of Perl sees numerous internal changes which
shouldn't affect day to day usage but may still be notable
for developers working with Perl's source code.
o The J.R.R. Tolkien quotes at the head of C source file
have been checked and proper citations added, thanks to
a patch from Tom Christiansen.
o The internal structure of the dual-life modules
traditionally found in the lib/ and ext/ directories in
the perl source has changed significantly. Where
possible, dual-lifed modules have been extracted from
lib/ and ext/.
Dual-lifed modules maintained by Perl's developers as
part of the Perl core now live in dist/. Dual-lifed
modules maintained primarily on CPAN now live in cpan/.
When reporting a bug in a module located under cpan/,
please send your bug report directly to the module's bug
tracker or author, rather than Perl's bug tracker.
o "\N{...}" now compiles better, always forces UTF-8
internal representation
Perl's developers have fixed several problems with the
recognition of "\N{...}" constructs. As part of this,
perl will store any scalar or regex containing
"\N{name}" or "\N{U+wide hex char}" in its definition in
UTF-8 format. (This was true previously for all
occurences of "\N{name}" that did not use a custom
translator, but now it's always true.)
o Perl_magic_setmglob now knows about globs, fixing RT
#71254.
o "SVt_RV" no longer exists. RVs are now stored in IVs.
o "Perl_vcroak()" now accepts a null first argument. In
addition, a full audit was made of the "not NULL"
compiler annotations, and those for several other
internal functions were corrected.
o New macros "dSAVEDERRNO", "dSAVE_ERRNO", "SAVE_ERRNO",
"RESTORE_ERRNO" have been added to formalise the
temporary saving of the "errno" variable.
o The function "Perl_sv_insert_flags" has been added to
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augment "Perl_sv_insert".
o The function "Perl_newSV_type(type)" has been added,
equivalent to "Perl_newSV()" followed by
"Perl_sv_upgrade(type)".
o The function "Perl_newSVpvn_flags()" has been added,
equivalent to "Perl_newSVpvn()" and then performing the
action relevant to the flag.
Two flag bits are currently supported.
o "SVf_UTF8" will call "SvUTF8_on()" for you. (Note
that this does not convert an sequence of ISO 8859-1
characters to UTF-8). A wrapper, "newSVpvn_utf8()"
is available for this.
o "SVs_TEMP" now calls "Perl_sv_2mortal()" on the new
SV.
There is also a wrapper that takes constant strings,
"newSVpvs_flags()".
o The function "Perl_croak_xs_usage" has been added as a
wrapper to "Perl_croak".
o Perl now exports the functions "PerlIO_find_layer" and
"PerlIO_list_alloc".
o "PL_na" has been exterminated from the core code,
replaced by local STRLEN temporaries, or "*_nolen()"
calls. Either approach is faster than "PL_na", which is
a pointer dereference into the interpreter structure
under ithreads, and a global variable otherwise.
o "Perl_mg_free()" used to leave freed memory accessible
via "SvMAGIC()" on the scalar. It now updates the linked
list to remove each piece of magic as it is freed.
o Under ithreads, the regex in "PL_reg_curpm" is now
reference counted. This eliminates a lot of hackish
workarounds to cope with it not being reference counted.
o "Perl_mg_magical()" would sometimes incorrectly turn on
"SvRMAGICAL()". This has been fixed.
o The public IV and NV flags are now not set if the string
value has trailing "garbage". This behaviour is
consistent with not setting the public IV or NV flags if
the value is out of range for the type.
o Uses of "Nullav", "Nullcv", "Nullhv", "Nullop", "Nullsv"
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etc have been replaced by "NULL" in the core code, and
non-dual-life modules, as "NULL" is clearer to those
unfamiliar with the core code.
o A macro MUTABLE_PTR(p) has been added, which on (non-
pedantic) gcc will not cast away "const", returning a
"void *". Macros "MUTABLE_SV(av)", "MUTABLE_SV(cv)" etc
build on this, casting to "AV *" etc without casting
away "const". This allows proper compile-time auditing
of "const" correctness in the core, and helped picked up
some errors (now fixed).
o Macros "mPUSHs()" and "mXPUSHs()" have been added, for
pushing SVs on the stack and mortalizing them.
o Use of the private structure "mro_meta" has changed
slightly. Nothing outside the core should be accessing
this directly anyway.
o A new tool, Porting/expand-macro.pl has been added, that
allows you to view how a C preprocessor macro would be
expanded when compiled. This is handy when trying to
decode the macro hell that is the perl guts.
Testing
Testing improvements
Parallel tests
The core distribution can now run its regression tests
in parallel on Unix-like platforms. Instead of running
"make test", set "TEST_JOBS" in your environment to the
number of tests to run in parallel, and run "make
test_harness". On a Bourne-like shell, this can be done
as
TEST_JOBS=3 make test_harness # Run 3 tests in parallel
An environment variable is used, rather than parallel
make itself, because TAP::Harness needs to be able to
schedule individual non-conflicting test scripts itself,
and there is no standard interface to "make" utilities
to interact with their job schedulers.
Note that currently some test scripts may fail when run
in parallel (most notably "ext/IO/t/io_dir.t"). If
necessary run just the failing scripts again
sequentially and see if the failures go away.
Test harness flexibility
It's now possible to override "PERL5OPT" and friends in
t/TEST
Test watchdog
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Several tests that have the potential to hang forever if
they fail now incorporate a "watchdog" functionality
that will kill them after a timeout, which helps ensure
that "make test" and "make test_harness" run to
completion automatically.
New Tests
Perl's developers have added a number of new tests to the
core. In addition to the items listed below, many modules
updated from CPAN incorporate new tests.
o Significant cleanups to core tests to ensure that
language and interpreter features are not used before
they're tested.
o "make test_porting" now runs a number of important pre-
commit checks which might be of use to anyone working on
the Perl core.
o t/porting/podcheck.t automatically checks the well-
formedness of POD found in all .pl, .pm and .pod files
in the MANIFEST, other than in dual-lifed modules which
are primarily maintained outside the Perl core.
o t/porting/manifest.t now tests that all files listed in
MANIFEST are present.
o t/op/while_readdir.t tests that a bare readdir in while
loop sets $_.
o t/comp/retainedlines.t checks that the debugger can
retain source lines from "eval".
o t/io/perlio_fail.t checks that bad layers fail.
o t/io/perlio_leaks.t checks that PerlIO layers are not
leaking.
o t/io/perlio_open.t checks that certain special forms of
open work.
o t/io/perlio.t includes general PerlIO tests.
o t/io/pvbm.t checks that there is no unexpected
interaction between the internal types "PVBM" and
"PVGV".
o t/mro/package_aliases.t checks that mro works properly
in the presence of aliased packages.
o t/op/dbm.t tests "dbmopen" and "dbmclose".
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o t/op/index_thr.t tests the interaction of "index" and
threads.
o t/op/pat_thr.t tests the interaction of esoteric
patterns and threads.
o t/op/qr_gc.t tests that "qr" doesn't leak.
o t/op/reg_email_thr.t tests the interaction of regex
recursion and threads.
o t/op/regexp_qr_embed_thr.t tests the interaction of
patterns with embedded "qr//" and threads.
o t/op/regexp_unicode_prop.t tests Unicode properties in
regular expressions.
o t/op/regexp_unicode_prop_thr.t tests the interaction of
Unicode properties and threads.
o t/op/reg_nc_tie.t tests the tied methods of
"Tie::Hash::NamedCapture".
o t/op/reg_posixcc.t checks that POSIX character classes
behave consistently.
o t/op/re.t checks that exportable "re" functions in
universal.c work.
o t/op/setpgrpstack.t checks that "setpgrp" works.
o t/op/substr_thr.t tests the interaction of "substr" and
threads.
o t/op/upgrade.t checks that upgrading and assigning
scalars works.
o t/uni/lex_utf8.t checks that Unicode in the lexer works.
o t/uni/tie.t checks that Unicode and "tie" work.
o t/comp/final_line_num.t tests whether line numbers are
correct at EOF
o t/comp/form_scope.t tests format scoping.
o t/comp/line_debug.t tests whether "@{"_<$file"}" works.
o t/op/filetest_t.t tests if -t file test works.
o t/op/qr.t tests "qr".
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o t/op/utf8cache.t tests malfunctions of the utf8 cache.
o t/re/uniprops.t test unicodes "\p{}" regex constructs.
o t/op/filehandle.t tests some suitably portable filetest
operators to check that they work as expected,
particularly in the light of some internal changes made
in how filehandles are blessed.
o t/op/time_loop.t tests that unix times greater than
"2**63", which can now be handed to "gmtime" and
"localtime", do not cause an internal overflow or an
excessively long loop.
New or Changed Diagnostics
New Diagnostics
o SV allocation tracing has been added to the diagnostics
enabled by "-Dm". The tracing can alternatively output
via the "PERL_MEM_LOG" mechanism, if that was enabled
when the perl binary was compiled.
o Smartmatch resolution tracing has been added as a new
diagnostic. Use "-DM" to enable it.
o A new debugging flag "-DB" now dumps subroutine
definitions, leaving "-Dx" for its original purpose of
dumping syntax trees.
o Perl 5.12 provides a number of new diagnostic messages
to help you write better code. See perldiag for details
of these new messages.
o "Bad plugin affecting keyword '%s'"
o "gmtime(%.0f) too large"
o "Lexing code attempted to stuff non-Latin-1
character into Latin-1 input"
o "Lexing code internal error (%s)"
o "localtime(%.0f) too large"
o "Overloaded dereference did not return a reference"
o "Overloaded qr did not return a REGEXP"
o "Perl_pmflag() is deprecated, and will be removed
from the XS API"
o "lvalue attribute ignored after the subroutine has
been defined"
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This new warning is issued when one attempts to mark
a subroutine as lvalue after it has been defined.
o Perl now warns you if "++" or "--" are unable to
change the value because it's beyond the limit of
representation.
This uses a new warnings category: "imprecision".
o "lc", "uc", "lcfirst", and "ucfirst" warn when
passed undef.
o "Show constant in "Useless use of a constant in void
context""
o "Prototype after '%s'"
o "panic: sv_chop %s"
This new fatal error occurs when the C routine
"Perl_sv_chop()" was passed a position that is not
within the scalar's string buffer. This could be
caused by buggy XS code, and at this point recovery
is not possible.
o The fatal error "Malformed UTF-8 returned by \N" is
now produced if the "charnames" handler returns
malformed UTF-8.
o If an unresolved named character or sequence was
encountered when compiling a regex pattern then the
fatal error "\N{NAME} must be resolved by the lexer"
is now produced. This can happen, for example, when
using a single-quotish context like "$re =
'\N{SPACE}'; /$re/;". See perldiag for more examples
of how the lexer can get bypassed.
o "Invalid hexadecimal number in \N{U+...}" is a new
fatal error triggered when the character constant
represented by "..." is not a valid hexadecimal
number.
o The new meaning of "\N" as "[^\n]" is not valid in a
bracketed character class, just like "." in a
character class loses its special meaning, and will
cause the fatal error "\N in a character class must
be a named character: \N{...}".
o The rules on what is legal for the "..." in
"\N{...}" have been tightened up so that unless the
"..." begins with an alphabetic character and
continues with a combination of alphanumerics,
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dashes, spaces, parentheses or colons then the
warning "Deprecated character(s) in \N{...} starting
at '%s'" is now issued.
o The warning "Using just the first characters
returned by \N{}" will be issued if the "charnames"
handler returns a sequence of characters which
exceeds the limit of the number of characters that
can be used. The message will indicate which
characters were used and which were discarded.
Changed Diagnostics
A number of existing diagnostic messages have been improved
or corrected:
o A new warning category "illegalproto" allows finer-
grained control of warnings around function prototypes.
The two warnings:
"Illegal character in prototype for %s : %s"
"Prototype after '%c' for %s : %s"
have been moved from the "syntax" top-level warnings
category into a new first-level category,
"illegalproto". These two warnings are currently the
only ones emitted during parsing of an invalid/illegal
prototype, so one can now use
no warnings 'illegalproto';
to suppress only those, but not other syntax-related
warnings. Warnings where prototypes are changed,
ignored, or not met are still in the "prototype"
category as before.
o "Deep recursion on subroutine "%s""
It is now possible to change the depth threshold for
this warning from the default of 100, by recompiling the
perl binary, setting the C pre-processor macro
"PERL_SUB_DEPTH_WARN" to the desired value.
o "Illegal character in prototype" warning is now more
precise when reporting illegal characters after _
o mro merging error messages are now very similar to those
produced by Algorithm::C3.
o Amelioration of the error message "Unrecognized
character %s in column %d"
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Changes the error message to "Unrecognized character %s;
marked by <-- HERE after %s<-- HERE near column %d".
This should make it a little simpler to spot and correct
the suspicious character.
o Perl now explicitly points to $. when it causes an
uninitialized warning for ranges in scalar context.
o "split" now warns when called in void context.
o "printf"-style functions called with too few arguments
will now issue the warning "Missing argument in %s"
[perl #71000]
o Perl now properly returns a syntax error instead of
segfaulting if "each", "keys", or "values" is used
without an argument.
o "tell()" now fails properly if called without an
argument and when no previous file was read.
"tell()" now returns "-1", and sets errno to "EBADF",
thus restoring the 5.8.x behaviour.
o "overload" no longer implicitly unsets fallback on
repeated 'use overload' lines.
o POSIX::strftime() can now handle Unicode characters in
the format string.
o The "syntax" category was removed from 5 warnings that
should only be in "deprecated".
o Three fatal "pack"/"unpack" error messages have been
normalized to "panic: %s"
o "Unicode character is illegal" has been rephrased to be
more accurate
It now reads "Unicode non-character is illegal in
interchange" and the perldiag documentation has been
expanded a bit.
o Currently, all but the first of the several characters
that the "charnames" handler may return are discarded
when used in a regular expression pattern bracketed
character class. If this happens then the warning "Using
just the first character returned by \N{} in character
class" will be issued.
o The warning "Missing right brace on \N{} or unescaped
left brace after \N. Assuming the latter" will be
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issued if Perl encounters a "\N{" but doesn't find a
matching "}". In this case Perl doesn't know if it was
mistakenly omitted, or if "match non-newline" followed
by "match a "{"" was desired. It assumes the latter
because that is actually a valid interpretation as
written, unlike the other case. If you meant the
former, you need to add the matching right brace. If
you did mean the latter, you can silence this warning by
writing instead "\N\{".
o "gmtime" and "localtime" called with numbers smaller
than they can reliably handle will now issue the
warnings "gmtime(%.0f) too small" and "localtime(%.0f)
too small".
The following diagnostic messages have been removed:
o "Runaway format"
o "Can't locate package %s for the parents of %s"
In general this warning it only got produced in
conjunction with other warnings, and removing it allowed
an ISA lookup optimisation to be added.
o "v-string in use/require is non-portable"
Utility Changes
o h2ph now looks in "include-fixed" too, which is a recent
addition to gcc's search path.
o h2xs no longer incorrectly treats enum values like
macros. It also now handles C++ style comments ("//")
properly in enums.
o perl5db.pl now supports "LVALUE" subroutines.
Additionally, the debugger now correctly handles proxy
constant subroutines, and subroutine stubs.
o perlbug now uses %Module::CoreList::bug_tracker to print
out upstream bug tracker URLs. If a user identifies a
particular module as the topic of their bug report and
we're able to divine the URL for its upstream bug
tracker, perlbug now provide a message to the user
explaining that the core copies the CPAN version
directly, and provide the URL for reporting the bug
directly to the upstream author.
perlbug no longer reports "Message sent" when it hasn't
actually sent the message
o perlthanks is a new utility for sending non-bug-reports
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to the authors and maintainers of Perl. Getting nothing
but bug reports can become a bit demoralising. If Perl
5.12 works well for you, please try out perlthanks. It
will make the developers smile.
o Perl's developers have fixed bugs in a2p having to do
with the "match()" operator in list context.
Additionally, a2p no longer generates code that uses the
$[ variable.
Selected Bug Fixes
o U+0FFFF is now a legal character in regular expressions.
o pp_qr now always returns a new regexp SV. Resolves RT
#69852.
Instead of returning a(nother) reference to the (pre-
compiled) regexp in the optree, use reg_temp_copy() to
create a copy of it, and return a reference to that.
This resolves issues about Regexp::DESTROY not being
called in a timely fashion (the original bug tracked by
RT #69852), as well as bugs related to blessing regexps,
and of assigning to regexps, as described in
correspondence added to the ticket.
It transpires that we also need to undo the SvPVX()
sharing when ithreads cloning a Regexp SV, because
mother_re is set to NULL, instead of a cloned copy of
the mother_re. This change might fix bugs with regexps
and threads in certain other situations, but as yet
neither tests nor bug reports have indicated any
problems, so it might not actually be an edge case that
it's possible to reach.
o Several compilation errors and segfaults when perl was
built with "-Dmad" were fixed.
o Fixes for lexer API changes in 5.11.2 which broke
NYTProf's savesrc option.
o "-t" should only return TRUE for file handles connected
to a TTY
The Microsoft C version of "isatty()" returns TRUE for
all character mode devices, including the
/dev/null-style "nul" device and printers like "lpt1".
o Fixed a regression caused by commit fafafbaf which
caused a panic during parameter passing [perl #70171]
o On systems which in-place edits without backup files,
-i'*' now works as the documentation says it does [perl
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#70802]
o Saving and restoring magic flags no longer loses
readonly flag.
o The malformed syntax "grep EXPR LIST" (note the missing
comma) no longer causes abrupt and total failure.
o Regular expressions compiled with "qr{}" literals
properly set "$'" when matching again.
o Using named subroutines with "sort" should no longer
lead to bus errors [perl #71076]
o Numerous bugfixes catch small issues caused by the
recently-added Lexer API.
o Smart match against @_ sometimes gave false negatives.
[perl #71078]
o $@ may now be assigned a read-only value (without error
or busting the stack).
o "sort" called recursively from within an active
comparison subroutine no longer causes a bus error if
run multiple times. [perl #71076]
o Tie::Hash::NamedCapture::* will not abort if passed bad
input (RT #71828)
o @_ and $_ no longer leak under threads (RT #34342 and
#41138, also #70602, #70974)
o "-I" on shebang line now adds directories in front of
@INC as documented, and as does "-I" when specified on
the command-line.
o "kill" is now fatal when called on non-numeric process
identifiers. Previously, an "undef" process identifier
would be interpreted as a request to kill process 0,
which would terminate the current process group on POSIX
systems. Since process identifiers are always integers,
killing a non-numeric process is now fatal.
o 5.10.0 inadvertently disabled an optimisation, which
caused a measurable performance drop in list assignment,
such as is often used to assign function parameters from
@_. The optimisation has been re-instated, and the
performance regression fixed. (This fix is also present
in 5.10.1)
o Fixed memory leak on "while (1) { map 1, 1 }" [RT
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#53038].
o Some potential coredumps in PerlIO fixed [RT
#57322,54828].
o The debugger now works with lvalue subroutines.
o The debugger's "m" command was broken on modules that
defined constants [RT #61222].
o "crypt" and string complement could return tainted
values for untainted arguments [RT #59998].
o The "-i".suffix command-line switch now recreates the
file using restricted permissions, before changing its
mode to match the original file. This eliminates a
potential race condition [RT #60904].
o On some Unix systems, the value in $? would not have the
top bit set ("$? & 128") even if the child core dumped.
o Under some circumstances, $^R could incorrectly become
undefined [RT #57042].
o In the XS API, various hash functions, when passed a
pre-computed hash where the key is UTF-8, might result
in an incorrect lookup.
o XS code including XSUB.h before perl.h gave a compile-
time error [RT #57176].
o "$object->isa('Foo')" would report false if the package
"Foo" didn't exist, even if the object's @ISA contained
"Foo".
o Various bugs in the new-to 5.10.0 mro code, triggered by
manipulating @ISA, have been found and fixed.
o Bitwise operations on references could crash the
interpreter, e.g. "$x=\$y; $x |= "foo"" [RT #54956].
o Patterns including alternation might be sensitive to the
internal UTF-8 representation, e.g.
my $byte = chr(192);
my $utf8 = chr(192); utf8::upgrade($utf8);
$utf8 =~ /$byte|X}/i; # failed in 5.10.0
o Within UTF8-encoded Perl source files (i.e. where "use
utf8" is in effect), double-quoted literal strings could
be corrupted where a "\xNN", "\0NNN" or "\N{}" is
followed by a literal character with ordinal value
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greater than 255 [RT #59908].
o "B::Deparse" failed to correctly deparse various
constructs: "readpipe STRING" [RT #62428],
"CORE::require(STRING)" [RT #62488], "sub foo(_)" [RT
#62484].
o Using "setpgrp" with no arguments could corrupt the perl
stack.
o The block form of "eval" is now specifically trappable
by "Safe" and "ops". Previously it was erroneously
treated like string "eval".
o In 5.10.0, the two characters "[~" were sometimes parsed
as the smart match operator ("~~") [RT #63854].
o In 5.10.0, the "*" quantifier in patterns was sometimes
treated as "{0,32767}" [RT #60034, #60464]. For example,
this match would fail:
("ab" x 32768) =~ /^(ab)*$/
o "shmget" was limited to a 32 bit segment size on a 64
bit OS [RT #63924].
o Using "next" or "last" to exit a "given" block no longer
produces a spurious warning like the following:
Exiting given via last at foo.pl line 123
o Assigning a format to a glob could corrupt the format;
e.g.:
*bar=*foo{FORMAT}; # foo format now bad
o Attempting to coerce a typeglob to a string or number
could cause an assertion failure. The correct error
message is now generated, "Can't coerce GLOB to $type".
o Under "use filetest 'access'", "-x" was using the wrong
access mode. This has been fixed [RT #49003].
o "length" on a tied scalar that returned a Unicode value
would not be correct the first time. This has been
fixed.
o Using an array "tie" inside in array "tie" could SEGV.
This has been fixed. [RT #51636]
o A race condition inside "PerlIOStdio_close()" has been
identified and fixed. This used to cause various
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threading issues, including SEGVs.
o In "unpack", the use of "()" groups in scalar context
was internally placing a list on the interpreter's
stack, which manifested in various ways, including
SEGVs. This is now fixed [RT #50256].
o Magic was called twice in "substr", "\&$x", "tie $x, $m"
and "chop". These have all been fixed.
o A 5.10.0 optimisation to clear the temporary stack
within the implicit loop of "s///ge" has been reverted,
as it turned out to be the cause of obscure bugs in
seemingly unrelated parts of the interpreter [commit
ef0d4e17921ee3de].
o The line numbers for warnings inside "elsif" are now
correct.
o The ".." operator now works correctly with ranges whose
ends are at or close to the values of the smallest and
largest integers.
o "binmode STDIN, ':raw'" could lead to segmentation
faults on some platforms. This has been fixed [RT
#54828].
o An off-by-one error meant that "index $str, ..." was
effectively being executed as "index "$str\0", ...".
This has been fixed [RT #53746].
o Various leaks associated with named captures in regexes
have been fixed [RT #57024].
o A weak reference to a hash would leak. This was
affecting "DBI" [RT #56908].
o Using (?|) in a regex could cause a segfault [RT
#59734].
o Use of a UTF-8 "tr//" within a closure could cause a
segfault [RT #61520].
o Calling "Perl_sv_chop()" or otherwise upgrading an SV
could result in an unaligned 64-bit access on the SPARC
architecture [RT #60574].
o In the 5.10.0 release, "inc_version_list" would
incorrectly list "5.10.*" after "5.8.*"; this affected
the @INC search order [RT #67628].
o In 5.10.0, "pack "a*", $tainted_value" returned a non-
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tainted value [RT #52552].
o In 5.10.0, "printf" and "sprintf" could produce the
fatal error "panic: utf8_mg_pos_cache_update" when
printing UTF-8 strings [RT #62666].
o In the 5.10.0 release, a dynamically created "AUTOLOAD"
method might be missed (method cache issue) [RT
#60220,60232].
o In the 5.10.0 release, a combination of "use feature"
and "//ee" could cause a memory leak [RT #63110].
o "-C" on the shebang ("#!") line is once more permitted
if it is also specified on the command line. "-C" on the
shebang line used to be a silent no-op if it was not
also on the command line, so perl 5.10.0 disallowed it,
which broke some scripts. Now perl checks whether it is
also on the command line and only dies if it is not [RT
#67880].
o In 5.10.0, certain types of re-entrant regular
expression could crash, or cause the following assertion
failure [RT #60508]:
Assertion rx->sublen >= (s - rx->subbeg) + i failed
o Perl now includes previously missing files from the
Unicode Character Database.
o Perl now honors "TMPDIR" when opening an anonymous
temporary file.
Platform Specific Changes
Perl is incredibly portable. In general, if a platform has a
C compiler, someone has ported Perl to it (or will soon).
We're happy to announce that Perl 5.12 includes support for
several new platforms. At the same time, it's time to bid
farewell to some (very) old friends.
New Platforms
Haiku
Perl's developers have merged patches from Haiku's
maintainers. Perl should now build on Haiku.
MirOS BSD
Perl should now build on MirOS BSD.
Discontinued Platforms
Domain/OS
MiNT
Tenon MachTen
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Updated Platforms
AIX
o Removed libbsd for AIX 5L and 6.1. Only "flock()"
was used from libbsd.
o Removed libgdbm for AIX 5L and 6.1 if libgdbm <
1.8.3-5 is installed. The libgdbm is delivered as
an optional package with the AIX Toolbox.
Unfortunately the versions below 1.8.3-5 are broken.
o Hints changes mean that AIX 4.2 should work again.
Cygwin
o Perl now supports IPv6 on Cygwin 1.7 and newer.
o On Cygwin we now strip the last number from the DLL.
This has been the behaviour in the cygwin.com build
for years. The hints files have been updated.
Darwin (Mac OS X)
o Skip testing the be_BY.CP1131 locale on Darwin 10
(Mac OS X 10.6), as it's still buggy.
o Correct infelicities in the regexp used to identify
buggy locales on Darwin 8 and 9 (Mac OS X 10.4 and
10.5, respectively).
DragonFly BSD
o Fix thread library selection [perl #69686]
FreeBSD
o The hints files now identify the correct threading
libraries on FreeBSD 7 and later.
Irix
o We now work around a bizarre preprocessor bug in the
Irix 6.5 compiler: "cc -E -" unfortunately goes into
K&R mode, but "cc -E file.c" doesn't.
NetBSD
o Hints now supports versions 5.*.
OpenVMS
o "-UDEBUGGING" is now the default on VMS.
Like it has been everywhere else for ages and ages.
Also make command-line selection of -UDEBUGGING and
-DDEBUGGING work in configure.com; before the only
way to turn it off was by saying no in answer to the
interactive question.
o The default pipe buffer size on VMS has been updated
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to 8192 on 64-bit systems.
o Reads from the in-memory temporary files of
"PerlIO::scalar" used to fail if $/ was set to a
numeric reference (to indicate record-style reads).
This is now fixed.
o VMS now supports "getgrgid".
o Many improvements and cleanups have been made to the
VMS file name handling and conversion code.
o Enabling the "PERL_VMS_POSIX_EXIT" logical name now
encodes a POSIX exit status in a VMS condition value
for better interaction with GNV's bash shell and
other utilities that depend on POSIX exit values.
See "$?" in perlvms for details.
o "File::Copy" now detects Unix compatibility mode on
VMS.
Stratus VOS
o Various changes from Stratus have been merged in.
Symbian
o There is now support for Symbian S60 3.2 SDK and S60
5.0 SDK.
Windows
o Perl 5.12 supports Windows 2000 and later. The
supporting code for legacy versions of Windows is
still included, but will be removed during the next
development cycle.
o Initial support for building Perl with MinGW-w64 is
now available.
o perl.exe now includes a manifest resource to specify
the "trustInfo" settings for Windows Vista and
later. Without this setting Windows would treat
perl.exe as a legacy application and apply various
heuristics like redirecting access to protected file
system areas (like the "Program Files" folder) to
the users "VirtualStore" instead of generating a
proper "permission denied" error.
The manifest resource also requests the Microsoft
Common-Controls version 6.0 (themed controls
introduced in Windows XP). Check out the
Win32::VisualStyles module on CPAN to switch back to
old style unthemed controls for legacy applications.
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o The "-t" filetest operator now only returns true if
the filehandle is connected to a console window. In
previous versions of Perl it would return true for
all character mode devices, including NUL and LPT1.
o The "-p" filetest operator now works correctly, and
the Fcntl::S_IFIFO constant is defined when Perl is
compiled with Microsoft Visual C. In previous Perl
versions "-p" always returned a false value, and the
Fcntl::S_IFIFO constant was not defined.
This bug is specific to Microsoft Visual C and never
affected Perl binaries built with MinGW.
o The socket error codes are now more widely
supported: The POSIX module will define the
symbolic names, like POSIX::EWOULDBLOCK, and
stringification of socket error codes in $! works as
well now;
C:\>perl -MPOSIX -E "$!=POSIX::EWOULDBLOCK; say $!"
A non-blocking socket operation could not be completed immediately.
o flock() will now set sensible error codes in $!.
Previous Perl versions copied the value of $^E into
$!, which caused much confusion.
o select() now supports all empty "fd_set"s more
correctly.
o '.\foo' and '..\foo' were treated differently than
'./foo' and '../foo' by "do" and "require" [RT
#63492].
o Improved message window handling means that "alarm"
and "kill" messages will no longer be dropped under
race conditions.
o Various bits of Perl's build infrastructure are no
longer converted to win32 line endings at release
time. If this hurts you, please report the problem
with the perlbug program included with perl.
Known Problems
This is a list of some significant unfixed bugs, which are
regressions from either 5.10.x or 5.8.x.
o Some CPANPLUS tests may fail if there is a functioning
file ../../cpanp-run-perl outside your build directory.
The failure shouldn't imply there's a problem with the
actual functional software. The bug is already fixed in
[RT #74188] and is scheduled for inclusion in
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perl-v5.12.1.
o "List::Util::first" misbehaves in the presence of a
lexical $_ (typically introduced by "my $_" or
implicitly by "given"). The variable which gets set for
each iteration is the package variable $_, not the
lexical $_ [RT #67694].
A similar issue may occur in other modules that provide
functions which take a block as their first argument,
like
foo { ... $_ ...} list
o Some regexes may run much more slowly when run in a
child thread compared with the thread the pattern was
compiled into [RT #55600].
o Things like ""\N{LATIN SMALL LIGATURE FF}" =~ /\N{LATIN
SMALL LETTER F}+/" will appear to hang as they get into
a very long running loop [RT #72998].
o Several porters have reported mysterious crashes when
Perl's entire test suite is run after a build on certain
Windows 2000 systems. When run by hand, the individual
tests reportedly work fine.
Errata
o This one is actually a change introduced in 5.10.0, but
it was missed from that release's perldelta, so it is
mentioned here instead.
A bugfix related to the handling of the "/m" modifier
and "qr" resulted in a change of behaviour between 5.8.x
and 5.10.0:
# matches in 5.8.x, doesn't match in 5.10.0
$re = qr/^bar/; "foo\nbar" =~ /$re/m;
Acknowledgements
Perl 5.12.0 represents approximately two years of
development since Perl 5.10.0 and contains over 750,000
lines of changes across over 3,000 files from over 200
authors and committers.
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 5.12.0:
Aaron Crane, Abe Timmerman, Abhijit Menon-Sen, Abigail, Adam
Russell, Adriano Ferreira, var Arnfjoer` Bjarmason, Alan
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Perl Programmers Reference Guide PERL5120DELTA(1)
Grover, Alexandr Ciornii, Alex Davies, Alex Vandiver,
Andreas Koenig, Andrew Rodland, andrew@sundale.net, Andy
Armstrong, Andy Dougherty, Jose AUGUSTE-ETIENNE, Benjamin
Smith, Ben Morrow, bharanee rathna, Bo Borgerson, Bo
Lindbergh, Brad Gilbert, Bram, Brendan O'Dea, brian d foy,
Charles Bailey, Chip Salzenberg, Chris 'BinGOs' Williams,
Christoph Lamprecht, Chris Williams, chromatic, Claes
Jakobsson, Craig A. Berry, Dan Dascalescu, Daniel Frederick
Crisman, Daniel M. Quinlan, Dan Jacobson, Dan Kogai, Dave
Mitchell, Dave Rolsky, David Cantrell, David Dick, David
Golden, David Mitchell, David M. Syzdek, David Nicol, David
Wheeler, Dennis Kaarsemaker, Dintelmann, Peter, Dominic
Dunlop, Dr.Ruud, Duke Leto, Enrico Sorcinelli, Eric Brine,
Father Chrysostomos, Florian Ragwitz, Frank Wiegand, Gabor
Szabo, Gene Sullivan, Geoffrey T. Dairiki, George Greer,
Gerard Goossen, Gisle Aas, Goro Fuji, Graham Barr, Green,
Paul, Hans Dieter Pearcey, Harmen, H. Merijn Brand, Hugo van
der Sanden, Ian Goodacre, Igor Sutton, Ingo Weinhold, James
Bence, James Mastros, Jan Dubois, Jari Aalto, Jarkko
Hietaniemi, Jay Hannah, Jerry Hedden, Jesse Vincent, Jim
Cromie, Jody Belka, John E. Malmberg, John Malmberg, John
Peacock, John Peacock via RT, John P. Linderman, John
Wright, Josh ben Jore, Jos I. Boumans, Karl Williamson,
Kenichi Ishigaki, Ken Williams, Kevin Brintnall, Kevin Ryde,
Kurt Starsinic, Leon Brocard, Lubomir Rintel, Luke Ross,
Marcel Gruenauer, Marcus Holland-Moritz, Mark Jason Dominus,
Marko Asplund, Martin Hasch, Mashrab Kuvatov, Matt Kraai,
Matt S Trout, Max Maischein, Michael Breen, Michael
Cartmell, Michael G Schwern, Michael Witten, Mike Giroux,
Milosz Tanski, Moritz Lenz, Nicholas Clark, Nick Cleaton,
Niko Tyni, Offer Kaye, Osvaldo Villalon, Paul Fenwick, Paul
Gaborit, Paul Green, Paul Johnson, Paul Marquess, Philip
Hazel, Philippe Bruhat, Rafael Garcia-Suarez, Rainer Tammer,
Rajesh Mandalemula, Reini Urban, Renee Baecker, Ricardo
Signes, Ricardo SIGNES, Richard Foley, Rich Rauenzahn, Rick
Delaney, Risto Kankkunen, Robert May, Roberto C. Sanchez,
Robin Barker, SADAHIRO Tomoyuki, Salvador Ortiz Garcia, Sam
Vilain, Scott Lanning, Sebastien Aperghis-Tramoni, Sergio
Durigan Junior, Shlomi Fish, Simon 'corecode' Schubert,
Sisyphus, Slaven Rezic, Smylers, Steffen Mueller, Steffen
Ullrich, Stepan Kasal, Steve Hay, Steven Schubiger, Steve
Peters, Tels, The Doctor, Tim Bunce, Tim Jenness, Todd
Rinaldo, Tom Christiansen, Tom Hukins, Tom Wyant, Tony Cook,
Torsten Schoenfeld, Tye McQueen, Vadim Konovalov, Vincent
Pit, Hio YAMASHINA, Yasuhiro Matsumoto, Yitzchak Scott-
Thoennes, Yuval Kogman, Yves Orton, Zefram, Zsban Ambrus
This is woefully incomplete as it's automatically generated
from version control history. In particular, it doesn't
include the names of the (very much appreciated)
contributors who reported issues in previous versions of
Perl that helped make Perl 5.12.0 better. For a more
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Perl Programmers Reference Guide PERL5120DELTA(1)
complete list of all of Perl's historical contributors,
please see the "AUTHORS" file in the Perl 5.12.0
distribution.
Our "retired" pumpkings Nicholas Clark and Rafael Garcia-
Suarez deserve special thanks for their brilliant and
substantive ongoing contributions. Nicholas personally
authored over 30% of the patches since 5.10.0. Rafael comes
in second in patch authorship with 11%, but is first by a
long shot in committing patches authored by others, pushing
44% of the commits since 5.10.0 in this category, often
after providing considerable coaching to the patch authors.
These statistics in no way comprise all of their
contributions, but express in shorthand that we couldn't
have done it without them.
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.
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
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 "perl -V", will be sent off
to perlbug@perl.org to be analyzed 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 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.
ATTRIBUTES
See attributes(5) for descriptions of the following
attributes:
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Perl Programmers Reference Guide PERL5120DELTA(1)
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | runtime/perl-512 |
+---------------+------------------+
|Stability | Uncommitted |
+---------------+------------------+
SEE ALSO
The Changes file for an explanation of how to view
exhaustive details on what changed.
The INSTALL file for how to build Perl.
The README file for general stuff.
The Artistic and Copying files for copyright information.
<http://dev.perl.org/perl5/errata.html> for a list of issues
found after this release, as well as a list of CPAN modules
known to be incompatible with this release.
NOTES
This software was built from source available at
https://java.net/projects/solaris-userland. The original
community source was downloaded from
http://www.cpan.org/src/5.0/perl-5.12.5.tar.bz2
Further information about this software can be found on the
open source community website at http://www.perl.org/.
perl v5.12.5 Last change: 2012-11-03 49