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:
- •
- $VERSION is parsed in exactly the same way as "use
NAME VERSION"
- •
- $VERSION is set at compile time
- •
- $VERSION is a version object that provides proper
overloading of comparison operators so comparing $VERSION to decimal
(1.23) or dotted-decimal (v1.2.3) version numbers works correctly.
- •
- Eliminates "$VERSION = ..." and "eval
$VERSION" clutter
- •
- As it requires VERSION to be a numeric literal or v-string
literal, it can be statically parsed by toolchain modules without
"eval" the way MM->parse_version does for "$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.
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.
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 "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.
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.
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.
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 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 treats 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)".)
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:
- •
- 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).
- •
- "%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.
- •
- 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.
- •
- "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).
- •
- "$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 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¶
- •
- 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.
- •
- The boolkeys op has moved to the group of hash ops. This
breaks binary compatibility.
- •
- 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".
- •
- The semantics of "use feature :5.10*" have
changed slightly. See "Modules and Pragmata" for more
information.
- •
- 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.
- •
- 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.
- •
- As part of the "ExtUtils::MakeMaker" upgrade, the
"ExtUtils::MakeMaker::bytes" and
"ExtUtils::MakeMaker::vmsish" modules have been removed from
this distribution.
- •
- "Module::CoreList" no longer contains the
%:patchlevel hash.
- •
- "length undef" now returns undef.
- •
- Unsupported private C API functions are now declared
"static" to prevent leakage to Perl's public API.
- •
- 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.
- •
- miniperl's @INC is now restricted to just
"-I...", the split of $ENV{PERL5LIB}, and
"".""
- •
- A space or a newline is now required after a "#line
XXX" directive.
- •
- Tied filehandles now have an additional method EOF which
provides the EOF type.
- •
- To better match all other flow control statements,
"foreach" may no longer be used as an attribute.
- •
- Perl's command-line switch "-P", which was
deprecated in version 5.10.0, has now been removed. The CPAN module
"Filter::cpp" can be used as an alternative.
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:
- 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 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 repercussions 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. 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. 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:
- •
- "\X" will not break apart a
"CR LF" sequence.
- •
- "\X" will now match a sequence which includes the
"ZWJ" and "ZWNJ" characters.
- •
- "\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.
- •
- "\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 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.
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.
- "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 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.
- "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"
- 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.
- "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"
- 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.
- "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"
- 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.
Documentation¶
New Documentation¶
- •
- perlhaiku contains instructions on how to build perl for
the Haiku platform.
- •
- perlmroapi describes the new interface for pluggable Method
Resolution Orders.
- •
- 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.
- •
- perlrepository describes how to access the perl source
using the git version control system.
- •
- perlpolicy extends the "Social contract about
contributed modules" into the beginnings of a document on Perl
porting policies.
Changes to Existing Documentation¶
- •
- 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.
- •
- 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.
- •
- 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.
- •
- Documented -X overloading.
- •
- Documented that "when()" treats specially most of
the filetest operators
- •
- Documented "when" as a syntax modifier.
- •
- Eliminated "Old Perl threads tutorial", which
described 5005 threads.
pod/perlthrtut.pod is the same material reworked for ithreads.
- •
- Correct previous documentation: v-strings are not
deprecated
With version objects, we need them to use MODULE VERSION syntax. This patch
removes the deprecation notice.
- •
- Security contact information is now part of perlsec.
- •
- 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.
- •
- 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.
- •
- 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".
- •
- The documentation for $1 in perlvar.pod has been
clarified.
- •
- "\N{U+code point}" is now documented.
- •
- A new internal cache means that "isa()" will
often be faster.
- •
- The implementation of "C3" Method Resolution
Order has been optimised - linearisation for classes with single
inheritance is 40% faster. Performance for multiple inheritance is
unchanged.
- •
- Under "use locale", the locale-relevant
information is now cached on read-only values, such as the list returned
by "keys %hash". This makes operations such as "sort keys
%hash" in the scope of "use locale" much faster.
- •
- Empty "DESTROY" methods are no longer
called.
- •
- "Perl_sv_utf8_upgrade()" is now faster.
- •
- "keys" on empty hash is now faster.
- •
- "if (%foo)" has been optimized to be faster than
"if (keys %foo)".
- •
- The string repetition operator ("$str x $num") is
now several times faster when $str has length one or $num is large.
- •
- 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¶
- •
- perlapi, perlintern, perlmodlib and perltoc are now all
generated at build time, rather than being shipped as part of the
release.
- •
- If "vendorlib" and "vendorarch" are the
same, then they are only added to @INC once.
- •
- $Config{usedevel} and the C-level
"PERL_USE_DEVEL" are now defined if perl is built with
"-Dusedevel".
- •
- Configure will enable use of
"-fstack-protector", to provide protection against
stack-smashing attacks, if the compiler supports it.
- •
- 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.
- •
- 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".
- •
- Perl now supports SystemTap's "dtrace"
compatibility layer and an issue with linking "miniperl" has
been fixed in the process.
- •
- perldoc now uses "less -R" instead of
"less" for improved behaviour in the face of "groff"'s
new usage of ANSI escape codes.
- •
- "perl -V" now reports use of the compile-time
options "USE_PERL_ATOF" and
"USE_ATTRIBUTES_FOR_PERLIO".
- •
- As part of the flattening of ext, all extensions on
all 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.
- •
- 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.
- •
- 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.
- •
- "\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+code point}" in its definition in UTF-8 format.
(This was true previously for all occurrences of "\N{
name}" that did not use a custom translator, but now it's
always true.)
- •
- Perl_magic_setmglob now knows about globs, fixing RT
#71254.
- •
- "SVt_RV" no longer exists. RVs are now stored in
IVs.
- •
- "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.
- •
- New macros "dSAVEDERRNO",
"dSAVE_ERRNO", "SAVE_ERRNO", "RESTORE_ERRNO"
have been added to formalise the temporary saving of the "errno"
variable.
- •
- The function "Perl_sv_insert_flags" has been
added to augment "Perl_sv_insert".
- •
- The function "Perl_newSV_type(type)" has been
added, equivalent to "Perl_newSV()" followed by
"Perl_sv_upgrade(type)".
- •
- 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.
- •
- "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.
- •
- "SVs_TEMP" now calls
"Perl_sv_2mortal()" on the new SV.
There is also a wrapper that takes constant strings,
"newSVpvs_flags()".
- •
- The function "Perl_croak_xs_usage" has been added
as a wrapper to "Perl_croak".
- •
- Perl now exports the functions
"PerlIO_find_layer" and "PerlIO_list_alloc".
- •
- "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.
- •
- "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.
- •
- 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.
- •
- "Perl_mg_magical()" would sometimes incorrectly
turn on "SvRMAGICAL()". This has been fixed.
- •
- 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.
- •
- Uses of "Nullav", "Nullcv",
"Nullhv", "Nullop", "Nullsv" 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.
- •
- 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).
- •
- Macros "mPUSHs()" and "mXPUSHs()" have
been added, for pushing SVs on the stack and mortalizing them.
- •
- Use of the private structure "mro_meta" has
changed slightly. Nothing outside the core should be accessing this
directly anyway.
- •
- 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
- 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.
- •
- Significant cleanups to core tests to ensure that language
and interpreter features are not used before they're tested.
- •
- "make test_porting" now runs a number of
important pre-commit checks which might be of use to anyone working on the
Perl core.
- •
- 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.
- •
- t/porting/manifest.t now tests that all files listed
in MANIFEST are present.
- •
- t/op/while_readdir.t tests that a bare readdir in
while loop sets $_.
- •
- t/comp/retainedlines.t checks that the debugger can
retain source lines from "eval".
- •
- t/io/perlio_fail.t checks that bad layers fail.
- •
- t/io/perlio_leaks.t checks that PerlIO layers are
not leaking.
- •
- t/io/perlio_open.t checks that certain special forms
of open work.
- •
- t/io/perlio.t includes general PerlIO tests.
- •
- t/io/pvbm.t checks that there is no unexpected
interaction between the internal types "PVBM" and
"PVGV".
- •
- t/mro/package_aliases.t checks that mro works
properly in the presence of aliased packages.
- •
- t/op/dbm.t tests "dbmopen" and
"dbmclose".
- •
- t/op/index_thr.t tests the interaction of
"index" and threads.
- •
- t/op/pat_thr.t tests the interaction of esoteric
patterns and threads.
- •
- t/op/qr_gc.t tests that "qr" doesn't
leak.
- •
- t/op/reg_email_thr.t tests the interaction of regex
recursion and threads.
- •
- t/op/regexp_qr_embed_thr.t tests the interaction of
patterns with embedded "qr//" and threads.
- •
- t/op/regexp_unicode_prop.t tests Unicode properties
in regular expressions.
- •
- t/op/regexp_unicode_prop_thr.t tests the interaction
of Unicode properties and threads.
- •
- t/op/reg_nc_tie.t tests the tied methods of
"Tie::Hash::NamedCapture".
- •
- t/op/reg_posixcc.t checks that POSIX character
classes behave consistently.
- •
- t/op/re.t checks that exportable "re"
functions in universal.c work.
- •
- t/op/setpgrpstack.t checks that "setpgrp"
works.
- •
- t/op/substr_thr.t tests the interaction of
"substr" and threads.
- •
- t/op/upgrade.t checks that upgrading and assigning
scalars works.
- •
- t/uni/lex_utf8.t checks that Unicode in the lexer
works.
- •
- t/uni/tie.t checks that Unicode and "tie"
work.
- •
- t/comp/final_line_num.t tests whether line numbers
are correct at EOF
- •
- t/comp/form_scope.t tests format scoping.
- •
- t/comp/line_debug.t tests whether
"@{"_<$file"}" works.
- •
- t/op/filetest_t.t tests if -t file test works.
- •
- t/op/qr.t tests "qr".
- •
- t/op/utf8cache.t tests malfunctions of the utf8
cache.
- •
- t/re/uniprops.t test unicodes "\p{}" regex
constructs.
- •
- 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.
- •
- 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¶
- •
- 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.
- •
- Smartmatch resolution tracing has been added as a new
diagnostic. Use "-DM" to enable it.
- •
- A new debugging flag "-DB" now dumps subroutine
definitions, leaving "-Dx" for its original purpose of dumping
syntax trees.
- •
- Perl 5.12 provides a number of new diagnostic messages to
help you write better code. See perldiag for details of these new
messages.
- •
- "Bad plugin affecting keyword '%s'"
- •
- "gmtime(%.0f) too large"
- •
- "Lexing code attempted to stuff non-Latin-1 character
into Latin-1 input"
- •
- "Lexing code internal error (%s)"
- •
- "localtime(%.0f) too large"
- •
- "Overloaded dereference did not return a
reference"
- •
- "Overloaded qr did not return a REGEXP"
- •
- "Perl_pmflag() is deprecated, and will be removed from
the XS API"
- •
- "lvalue attribute ignored after the subroutine has
been defined"
This new warning is issued when one attempts to mark a subroutine as lvalue
after it has been defined.
- •
- 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".
- •
- "lc", "uc", "lcfirst", and
"ucfirst" warn when passed undef.
- •
- "Show constant in "Useless use of a constant in
void context""
- •
- "Prototype after '%s'"
- •
- "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.
- •
- The fatal error "Malformed UTF-8 returned by \N"
is now produced if the "charnames" handler returns malformed
UTF-8.
- •
- 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.
- •
- "Invalid hexadecimal number in \N{U+...}" is a
new fatal error triggered when the character constant represented by
"..." is not a valid hexadecimal number.
- •
- 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{...}".
- •
- 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, dashes, spaces, parentheses or colons then
the warning "Deprecated character(s) in \N{...} starting at
'%s'" is now issued.
- •
- 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:
- •
- 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.
- •
- "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.
- •
- "Illegal character in prototype" warning is now
more precise when reporting illegal characters after _
- •
- mro merging error messages are now very similar to those
produced by Algorithm::C3.
- •
- Amelioration of the error message "Unrecognized
character %s in column %d"
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.
- •
- Perl now explicitly points to $. when it causes an
uninitialized warning for ranges in scalar context.
- •
- "split" now warns when called in void
context.
- •
- "printf"-style functions called with too few
arguments will now issue the warning "Missing argument in %s"
[perl #71000]
- •
- Perl now properly returns a syntax error instead of
segfaulting if "each", "keys", or "values"
is used without an argument.
- •
- "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.
- •
- "overload" no longer implicitly unsets fallback
on repeated 'use overload' lines.
- •
- POSIX::strftime() can now handle Unicode characters
in the format string.
- •
- The "syntax" category was removed from 5 warnings
that should only be in "deprecated".
- •
- Three fatal "pack"/"unpack" error
messages have been normalized to "panic: %s"
- •
- "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.
- •
- 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.
- •
- The warning "Missing right brace on \N{} or unescaped
left brace after \N. Assuming the latter" will be 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\{".
- •
- "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:
- •
- "Runaway format"
- •
- "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.
- •
- "v-string in use/require is non-portable"
Utility Changes¶
- •
- h2ph now looks in "include-fixed" too,
which is a recent addition to gcc's search path.
- •
- h2xs no longer incorrectly treats enum values like
macros. It also now handles C++ style comments ("//") properly
in enums.
- •
- perl5db.pl now supports "LVALUE"
subroutines. Additionally, the debugger now correctly handles proxy
constant subroutines, and subroutine stubs.
- •
- 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
- •
- perlthanks is a new utility for sending
non-bug-reports 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.
- •
- 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 $[ variable.
Selected Bug Fixes¶
- •
- U+0FFFF is now a legal character in regular
expressions.
- •
- pp_qr now always returns a new regexp SV. Resolves RT
#69852.
Instead of returning a(nother) reference to the (pre-compiled) regexp in the
optree, use reg_temp_copy() to create a copy of it, and return a
reference to that. This resolves issues about Regexp::DESTROY not being
called in a timely fashion (the original bug tracked by RT #69852), as
well as bugs related to blessing regexps, and of assigning to regexps, as
described in correspondence added to the ticket.
It transpires that we also need to undo the SvPVX() sharing when
ithreads cloning a Regexp SV, because mother_re is set to NULL, instead of
a cloned copy of the mother_re. This change might fix bugs with regexps
and threads in certain other situations, but as yet neither tests nor bug
reports have indicated any problems, so it might not actually be an edge
case that it's possible to reach.
- •
- Several compilation errors and segfaults when perl was
built with "-Dmad" were fixed.
- •
- Fixes for lexer API changes in 5.11.2 which broke NYTProf's
savesrc option.
- •
- "-t" should only return TRUE for file handles
connected to a TTY
The Microsoft C version of "isatty()" returns TRUE for all
character mode devices, including the /dev/null-style
"nul" device and printers like "lpt1".
- •
- Fixed a regression caused by commit fafafbaf which caused a
panic during parameter passing [perl #70171]
- •
- On systems which in-place edits without backup files, -i'*'
now works as the documentation says it does [perl #70802]
- •
- Saving and restoring magic flags no longer loses readonly
flag.
- •
- The malformed syntax "grep EXPR LIST" (note the
missing comma) no longer causes abrupt and total failure.
- •
- Regular expressions compiled with "qr{}" literals
properly set "$'" when matching again.
- •
- Using named subroutines with "sort" should no
longer lead to bus errors [perl #71076]
- •
- Numerous bugfixes catch small issues caused by the
recently-added Lexer API.
- •
- Smart match against @_ sometimes gave false negatives.
[perl #71078]
- •
- $@ may now be assigned a read-only value (without error or
busting the stack).
- •
- "sort" called recursively from within an active
comparison subroutine no longer causes a bus error if run multiple times.
[perl #71076]
- •
- Tie::Hash::NamedCapture::* will not abort if passed bad
input (RT #71828)
- •
- @_ and $_ no longer leak under threads (RT #34342 and
#41138, also #70602, #70974)
- •
- "-I" on shebang line now adds directories in
front of @INC as documented, and as does "-I" when specified on
the command-line.
- •
- "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.
- •
- 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)
- •
- Fixed memory leak on "while (1) { map 1, 1 }" [RT
#53038].
- •
- Some potential coredumps in PerlIO fixed [RT
#57322,54828].
- •
- The debugger now works with lvalue subroutines.
- •
- The debugger's "m" command was broken on modules
that defined constants [RT #61222].
- •
- "crypt" and string complement could return
tainted values for untainted arguments [RT #59998].
- •
- 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].
- •
- On some Unix systems, the value in $? would not have the
top bit set ("$? & 128") even if the child core dumped.
- •
- Under some circumstances, $^R could incorrectly become
undefined [RT #57042].
- •
- In the XS API, various hash functions, when passed a
pre-computed hash where the key is UTF-8, might result in an incorrect
lookup.
- •
- XS code including XSUB.h before perl.h gave a
compile-time error [RT #57176].
- •
- "$object->isa('Foo')" would report false if
the package "Foo" didn't exist, even if the object's @ISA
contained "Foo".
- •
- Various bugs in the new-to 5.10.0 mro code, triggered by
manipulating @ISA, have been found and fixed.
- •
- Bitwise operations on references could crash the
interpreter, e.g. "$x=\$y; $x |= "foo"" [RT
#54956].
- •
- 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
- •
- 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 greater than 255 [RT
#59908].
- •
- "B::Deparse" failed to correctly deparse various
constructs: "readpipe STRING" [RT #62428],
"CORE::require(STRING)" [RT #62488], "sub foo(_)" [RT
#62484].
- •
- Using "setpgrp" with no arguments could corrupt
the perl stack.
- •
- The block form of "eval" is now specifically
trappable by "Safe" and "ops". Previously it was
erroneously treated like string "eval".
- •
- In 5.10.0, the two characters "[~" were sometimes
parsed as the smart match operator ("~~") [RT #63854].
- •
- 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)*$/
- •
- "shmget" was limited to a 32 bit segment size on
a 64 bit OS [RT #63924].
- •
- 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
- •
- Assigning a format to a glob could corrupt the format;
e.g.:
*bar=*foo{FORMAT}; # foo format now bad
- •
- 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 $type".
- •
- Under "use filetest 'access'", "-x" was
using the wrong access mode. This has been fixed [RT #49003].
- •
- "length" on a tied scalar that returned a Unicode
value would not be correct the first time. This has been fixed.
- •
- Using an array "tie" inside in array
"tie" could SEGV. This has been fixed. [RT #51636]
- •
- A race condition inside "PerlIOStdio_close()" has
been identified and fixed. This used to cause various threading issues,
including SEGVs.
- •
- In "unpack", the use of "()" groups in
scalar context was internally placing a list on the interpreter's stack,
which manifested in various ways, including SEGVs. This is now fixed [RT
#50256].
- •
- Magic was called twice in "substr",
"\&$x", "tie $x, $m" and "chop". These
have all been fixed.
- •
- 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].
- •
- The line numbers for warnings inside "elsif" are
now correct.
- •
- The ".." operator now works correctly with ranges
whose ends are at or close to the values of the smallest and largest
integers.
- •
- "binmode STDIN, ':raw'" could lead to
segmentation faults on some platforms. This has been fixed [RT
#54828].
- •
- An off-by-one error meant that "index $str, ..."
was effectively being executed as "index "$str\0",
...". This has been fixed [RT #53746].
- •
- Various leaks associated with named captures in regexes
have been fixed [RT #57024].
- •
- A weak reference to a hash would leak. This was affecting
"DBI" [RT #56908].
- •
- Using (?|) in a regex could cause a segfault [RT
#59734].
- •
- Use of a UTF-8 "tr//" within a closure could
cause a segfault [RT #61520].
- •
- Calling "Perl_sv_chop()" or otherwise upgrading
an SV could result in an unaligned 64-bit access on the SPARC architecture
[RT #60574].
- •
- 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].
- •
- In 5.10.0, "pack "a*", $tainted_value"
returned a non-tainted value [RT #52552].
- •
- 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].
- •
- In the 5.10.0 release, a dynamically created
"AUTOLOAD" method might be missed (method cache issue) [RT
#60220,60232].
- •
- In the 5.10.0 release, a combination of "use
feature" and "//ee" could cause a memory leak [RT
#63110].
- •
- "-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].
- •
- 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
- •
- Perl now includes previously missing files from the Unicode
Character Database.
- •
- Perl now honors "TMPDIR" when opening an
anonymous temporary file.
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.
- 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.
- Domain/OS
- MiNT
- Tenon MachTen
- AIX
- •
- Removed libbsd for AIX 5L and 6.1. Only
"flock()" was used from libbsd.
- •
- 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.
- •
- Hints changes mean that AIX 4.2 should work again.
- Cygwin
- •
- Perl now supports IPv6 on Cygwin 1.7 and newer.
- •
- 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)
- •
- Skip testing the be_BY.CP1131 locale on Darwin 10 (Mac OS X
10.6), as it's still buggy.
- •
- 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
- •
- Fix thread library selection [perl #69686]
- FreeBSD
- •
- The hints files now identify the correct threading
libraries on FreeBSD 7 and later.
- Irix
- •
- 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
- •
- Hints now supports versions 5.*.
- OpenVMS
- •
- "-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.
- •
- The default pipe buffer size on VMS has been updated to
8192 on 64-bit systems.
- •
- Reads from the in-memory temporary files of
"PerlIO::scalar" used to fail if $/ was set to a numeric
reference (to indicate record-style reads). This is now fixed.
- •
- VMS now supports "getgrgid".
- •
- Many improvements and cleanups have been made to the VMS
file name handling and conversion code.
- •
- Enabling the "PERL_VMS_POSIX_EXIT" logical name
now encodes a POSIX exit status in a VMS condition value for better
interaction with GNV's bash shell and other utilities that depend on POSIX
exit values. See "$?" in perlvms for details.
- •
- "File::Copy" now detects Unix compatibility mode
on VMS.
- Stratus VOS
- •
- Various changes from Stratus have been merged in.
- Symbian
- •
- There is now support for Symbian S60 3.2 SDK and S60 5.0
SDK.
- Windows
- •
- 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.
- •
- Initial support for building Perl with MinGW-w64 is now
available.
- •
- 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.
- •
- 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.
- •
- 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.
- •
- 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.
- •
- flock() will now set sensible error codes in $!.
Previous Perl versions copied the value of $^E into $!, which caused much
confusion.
- •
- select() now supports all empty "fd_set"s
more correctly.
- •
- '.\foo' and '..\foo' were treated differently than './foo'
and '../foo' by "do" and "require" [RT #63492].
- •
- Improved message window handling means that
"alarm" and "kill" messages will no longer be dropped
under race conditions.
- •
- 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.
- •
- 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
perl-v5.12.1.
- •
- "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
- •
- Some regexes may run much more slowly when run in a child
thread compared with the thread the pattern was compiled into [RT
#55600].
- •
- 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].
- •
- 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¶
- •
- 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, AEvar Arnfjoerd` Bjarmason, Alan 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 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.
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.