PERL5100DELTA(1)
๐ PERL5100DELTA ๐
okay bestie, gather round, because this is perl5100delta โ the tea on what is new for perl 5.10.0. it's a long one so buckle up, this is part 1 of 7 ๐ซถ
โจ NAME โจ
perl5100delta โ what is new for perl 5.10.0
๐ธ DESCRIPTION ๐ธ
This document describes the differences between the 5.8.8 release and the 5.10.0 release.
Many of the bug fixes in 5.10.0 were already seen in the 5.8.X maintenance releases; they are not duplicated here and are documented in the set of man pages named perl58[1-8]?delta.
๐ Core Enhancements ๐
๐ The feature pragma ๐
The feature pragma is used to enable new syntax that would break Perl's backwards-compatibility with older releases of the language. It's a lexical pragma, like strict or warnings.
Currently the following new features are available: switch (adds a switch statement), say (adds a say built-in function), and state (adds a state keyword for declaring "static" variables). Those features are described in their own sections of this document.
The feature pragma is also implicitly loaded when you require a minimal perl version (with the use VERSION construct) greater than, or equal to, 5.9.5. See feature for details.
๐ New -E command-line switch ๐
-E is equivalent to -e, but it implicitly enables all optional features (like use feature ":5.10").
๐ Defined-or operator ๐
A new operator // (defined-or) has been implemented. The following expression:
$a // $b
is merely equivalent to
defined $a ? $a : $b
and the statement
$c //= $d;
can now be used instead of
$c = $d unless defined $c;
The // operator has the same precedence and associativity as ||. Special care has been taken to ensure that this operator Do What You Mean while not breaking old code, but some edge cases involving the empty regular expression may now parse differently. See perlop for details.
ngl, that "may now parse differently" bit is real โ if you're out here with empty regex edge cases, go read perlop, bestie, don't get caught slipping ๐
๐ฆ Switch and Smart Match operator ๐ฆ
Perl 5 now has a switch statement. It's available when use feature 'switch' is in effect. This feature introduces three new keywords, given, when, and default:
given ($foo) {
when (/^abc/) { $abc = 1; }
when (/^def/) { $def = 1; }
when (/^xyz/) { $xyz = 1; }
default { $nothing = 1; }
}
A more complete description of how Perl matches the switch variable against the when conditions is given in "Switch statements" in perlsyn.
This kind of match is called smart match, and it's also possible to use it outside of switch statements, via the new ~~ operator. See "Smart matching in detail" in perlsyn.
This feature was contributed by Robin Houston.
๐ Regular expressions ๐
๐ฅ Recursive Patterns ๐ฅ
It is now possible to write recursive patterns without using the (??{}) construct. This new way is more efficient, and in many cases easier to read.
Each capturing parenthesis can now be treated as an independent pattern that can be entered by using the (?PARNO) syntax (PARNO standing for "parenthesis number"). For example, the following pattern will match nested balanced angle brackets:
/
^ # start of line
( # start capture buffer 1
< # match an opening angle bracket
(?: # match one of:
(?> # don't backtrack over the inside of this group
[^<>]+ # one or more non angle brackets
) # end non backtracking group
| # ... or ...
(?1) # recurse to bracket 1 and try it again
)* # 0 or more times.
> # match a closing angle bracket
) # end capture buffer one
$ # end of line
/x
PCRE users should note that Perl's recursive regex feature allows backtracking into a recursed pattern, whereas in PCRE the recursion is atomic or "possessive" in nature. As in the example above, you can add (?>) to control this selectively. (Yves Orton)
๐ Named Capture Buffers ๐
It is now possible to name capturing parenthesis in a pattern and refer to the captured contents by name. The naming syntax is (?<NAME>....). It's possible to backreference to a named buffer with the \k<NAME> syntax. In code, the new magical hashes %+ and %- can be used to access the contents of the capture buffers.
Thus, to replace all doubled chars with a single copy, one could write
s/(?<letter>.)\k<letter>/$+{letter}/g
Only buffers with defined contents will be "visible" in the %+ hash, so it's possible to do something like
foreach my $name (keys %+) {
print "content of buffer '$name' is $+{$name}\n";
}
The %- hash is a bit more complete, since it will contain array refs holding values from all capture buffers similarly named, if there should be many of them.
%+ and %- are implemented as tied hashes through the new module Tie::Hash::NamedCapture.
Users exposed to the .NET regex engine will find that the perl implementation differs in that the numerical ordering of the buffers is sequential, and not "unnamed first, then named". Thus in the pattern
/(A)(?<B>B)(C)(?<D>D)/
$1 will be 'A', $2 will be 'B', $3 will be 'C' and $4 will be 'D' and not $1 is 'A', $2 is 'C' and $3 is 'B' and $4 is 'D' that a .NET programmer would expect. This is considered a feature. :-) (Yves Orton)
โญ Possessive Quantifiers โญ
Perl now supports the "possessive quantifier" syntax of the "atomic match" pattern. Basically a possessive quantifier matches as much as it can and never gives any back. Thus it can be used to control backtracking. The syntax is similar to non-greedy matching, except instead of using a '?' as the modifier the '+' is used. Thus ?+, *+, ++, {min,max}+ are now legal quantifiers. (Yves Orton)
๐ Backtracking control verbs ๐
The regex engine now supports a number of special-purpose backtrack control verbs: (*THEN), (*PRUNE), (*MARK), (*SKIP), (*COMMIT), (*FAIL) and (*ACCEPT). See perlre for their descriptions. (Yves Orton)
๐ Relative backreferences ๐
A new syntax \g{N} or \gN where N is a decimal integer allows a safer form of back-reference notation as well as allowing relative backreferences. This should make it easier to generate and embed patterns that contain backreferences. See "Capture buffers" in perlre. (Yves Orton)
๐ง \K escape ๐ง
The functionality of Jeff Pinyan's module Regexp::Keep has been added to the core. In regular expressions you can now use the special escape \K as a way to do something like floating length positive lookbehind. It is also useful in substitutions like:
s/(foo)bar/$1/g
that can now be converted to
s/foo\Kbar//g
which is much more efficient. (Yves Orton)
๐ธ Vertical and horizontal whitespace, and linebreak ๐ธ
Regular expressions now recognize the \v and \h escapes that match vertical and horizontal whitespace, respectively. \V and \H logically match their complements.
\R matches a generic linebreak, that is, vertical whitespace, plus the multi-character sequence \x0D\x0A.
๐ซถ Optional pre-match and post-match captures with the /p flag ๐ซถ
There is a new flag /p for regular expressions. Using this makes the engine preserve a copy of the part of the matched string before the matching substring to the new special variable ${^PREMATCH}, the part after the matching substring to ${^POSTMATCH}, and the matched substring itself to ${^MATCH}.
Perl is still able to store these substrings to the special variables $`, $', $&, but using these variables anywhere in the program adds a penalty to all regular expression matches, whereas if you use the /p flag and the new special variables instead, you pay only for the regular expressions where the flag is used.
For more detail on the new variables, see perlvar; for the use of the regular expression flag, see perlop and perlre.
๐ say() ๐
say() is a new built-in, only available when use feature 'say' is in effect, that is similar to print(), but that implicitly appends a newline to the printed string. See "say" in perlfunc. (Robin Houston)
โจ Lexical $_ โจ
The default variable $_ can now be lexicalized, by declaring it like any other lexical variable, with a simple
my $_;
The operations that default on $_ will use the lexically-scoped version of $_ when it exists, instead of the global $_.
In a map or a grep block, if $_ was previously my'ed, then the $_ inside the block is lexical as well (and scoped to the block).
In a scope where $_ has been lexicalized, you can still have access to the global version of $_ by using $::_, or, more simply, by overriding the lexical declaration with our $_. (Rafael Garcia-Suarez)
๐ The _ prototype ๐
A new prototype character has been added. _ is equivalent to $ but defaults to $_ if the corresponding argument isn't supplied (both $ and _ denote a scalar). Due to the optional nature of the argument, you can only use it at the end of a prototype, or before a semicolon.
This has a small incompatible consequence: the prototype() function has been adjusted to return _ for some built-ins in appropriate cases (for example, prototype('CORE::rmdir')). (Rafael Garcia-Suarez)
๐ UNITCHECK blocks ๐
UNITCHECK, a new special code block has been introduced, in addition to BEGIN, CHECK, INIT and END.
CHECK and INIT blocks, while useful for some specialized purposes, are always executed at the transition between the compilation and the execution of the main program, and thus are useless whenever code is loaded at runtime. On the other hand, UNITCHECK blocks are executed just after the unit which defined them has been compiled. See perlmod for more information. (Alex Gough)
๐ New Pragma, mro ๐
A new pragma, mro (for Method Resolution Order) has been added. It permits to switch, on a per-class basis, the algorithm that perl uses to find inherited methods in case of a multiple inheritance hierarchy. The default MRO hasn't changed (DFS, for Depth First Search). Another MRO is available: the C3 algorithm. See mro for more information. (Brandon Black)
Ok so quick heads-up bestie ๐ โ if your code used to undef the *ISA glob, it's most probably gonna break, because the class hierarchy search got reimplemented. And ngl, undef-ing *ISA was never it anyway: it had the side effect of ripping the magic off the @ISA array, which was never the vibe in the first place. Also the cache *::ISA::CACHE:: straight up no longer exists ๐ญ. So if you need to force-reset the @ISA cache, you now have to use the mro API, or honestly just do the simplest thing and assign to @ISA (like, e.g., with @ISA = @ISA). Periodt.
โจ readdir() may return a "short filename" on Windows โจ
So here's the thing: readdir() can hand you back a "short filename" whenever the long filename has characters outside the ANSI codepage ๐. Same energy for Cwd::cwd(), which may return a short directory name, and glob() may return short names too. On the NTFS file system, these short names can always be represented in the ANSI codepage โ iconic. But that is not true for all other file system drivers. Like, the FAT filesystem stores short filenames in the OEM codepage, so some files on FAT volumes stay inaccessible through the ANSI APIs. Not slay.
Similarly, $^X, @INC, and $ENV{PATH} get preprocessed at startup to make sure all paths are valid in the ANSI codepage (if possible).
The Win32::GetLongPathName() function now returns the UTF-8 encoded correct long file name instead of using replacement characters to force the name into the ANSI codepage ๐
. And the new Win32::GetANSIPathName() function can turn a long pathname into a short one โ but only if the long one cannot be represented in the ANSI codepage. Many other functions in the Win32 module also got glow-ups so they accept UTF-8 encoded arguments. Please see Win32 for details.
โจ readpipe() is now overridable โจ
The built-in function readpipe() is now overridable ๐ฅ. And the fun part? Overriding it also lets you override its operator counterpart, qx// (a.k.a. the backtick operator). On top of that, it now defaults to $_ if no argument is provided. (Rafael Garcia-Suarez)
โจ Default argument for readline() โจ
readline() now defaults to *ARGV if no argument is provided. (Rafael Garcia-Suarez)
โจ state() variables โจ
A whole new class of variables just dropped ๐. State variables are similar to my variables, except you declare them with the state keyword instead of my. They're visible only in their lexical scope, but their value is persistent: unlike my variables, they're not undefined at scope entry โ they retain their previous value. (Rafael Garcia-Suarez, Nicholas Clark)
To use state variables, you need to enable them, like:
use feature 'state';
or by using the -E command-line switch in one-liners. See "Persistent Private Variables" in perlsub.
โจ Stacked filetest operators โจ
New syntactic sugar alert ๐ โ you can now stack up filetest operators. So you can write -f -w -x $file in a row and it means -x $file && -w _ && -f _. See "-X" in perlfunc.
โจ UNIVERSAL::DOES() โจ
The UNIVERSAL class got a brand new method: DOES() ๐ฆ. It exists to solve semantic problems with the isa() method. isa() checks for inheritance, while DOES() was designed to be overridden when module authors use other types of relations between classes (in addition to inheritance). (chromatic)
See "$obj->DOES( ROLE )" in UNIVERSAL.
โจ Formats โจ
Formats got improved in several ways ๐. There's a new field, ^*, that you can use for variable-width, one-line-at-a-time text. Null characters are now handled correctly in picture lines. And using @# and ~~ together will now produce a compile-time error, because those format fields are incompatible โ so don't do that ๐
. perlform has been improved, and miscellaneous bugs got fixed.
โจ Byte-order modifiers for pack() and unpack() โจ
Two new byte-order modifiers entered the chat: > (big-endian) and < (little-endian) โจ. You can append them to most pack() and unpack() template characters and groups to force a certain byte-order for that type or group. See "pack" in perlfunc and perlpacktut for details.
โจ "no VERSION" โจ
You can now use no followed by a version number to specify that you want to use a version of perl older than the specified one.
โจ "chdir", "chmod" and "chown" on filehandles โจ
chdir, chmod and chown can now work on filehandles as well as filenames โ if the system supports respectively fchdir, fchmod and fchown. Thanks to a patch provided by Gisle Aas ๐ซถ.
โจ OS groups โจ
$( and $) now return groups in the order where the OS returns them, thanks to Gisle Aas. This wasn't previously the case, so yeah, glow-up.
โจ Recursive sort subs โจ
You can now use recursive subroutines with sort(), thanks to Robin Houston ๐ธ.
โจ Exceptions in constant folding โจ
The constant folding routine is now wrapped in an exception handler, and if folding throws an exception (such as attempting to evaluate 0/0), perl now retains the current optree rather than aborting the whole program ๐. Without this change, programs would not compile if they had expressions that happened to generate exceptions โ even though those expressions were in code that could never be reached at runtime. (Nicholas Clark, Dave Mitchell)
โจ Source filters in @INC โจ
You can now enhance the mechanism of subroutine hooks in @INC by adding a source filter on top of the filehandle opened and returned by the hook ๐ง. This feature was planned a long time ago, but wasn't quite working until now. See "require" in perlfunc for details. (Nicholas Clark)
โจ New internal variables โจ
${^RE_DEBUG_FLAGS}โ this variable controls what debug flags are in effect for the regular expression engine when running underuse re "debug". See re for details.${^CHILD_ERROR_NATIVE}โ this variable gives the native status returned by the last pipe close, backtick command, successful call towait()orwaitpid(), or from thesystem()operator. See perlvar for details. (Contributed by Gisle Aas.)${^RE_TRIE_MAXBUF}โ see "Trie optimisation of literal string alternations".${^WIN32_SLOPPY_STAT}โ see "Sloppy stat on Windows".
โจ Miscellaneous โจ
unpack()now defaults to unpacking the$_variable.mkdir()without arguments now defaults to$_.- The internal dump output has been improved, so that non-printable characters such as newline and backspace are output in
\xnotation, rather than octal. - The
-Coption can no longer be used on the#!line. It wasn't working there anyway, since the standard streams are already set up at this point in the execution of the perl interpreter. You can usebinmode()instead to get the desired behaviour.
โจ UCD 5.0.0 โจ
The copy of the Unicode Character Database included in Perl 5 has been updated to version 5.0.0 ๐.
โจ MAD โจ
MAD stands for Miscellaneous Attribute Decoration, and it's a still-in-development work leading to a Perl 5 to Perl 6 converter ๐ฎ. To enable it, it's necessary to pass the argument -Dmad to Configure.
Bestie, fair warning ๐ญ โ the obtained perl isn't binary compatible with a regular perl 5.10, and it has space and speed penalties; moreover not all regression tests still pass with it. (Larry Wall, Nicholas Clark)
โจ kill() on Windows โจ
On Windows platforms, kill(-9, $pid) now kills a process tree ๐. (On Unix, this delivers the signal to all processes in the same process group.)
๐ Incompatible Changes ๐
Okay bestie, this is the section where we say goodbye to some stuff and switch up how other stuff works. It's giving glow-up, but it's also giving "your old code might be a lil sad." Read carefully, no cap. ๐ซถ
๐ Packing and UTF-8 strings ๐
So pack() and unpack()? Their whole relationship with UTF-8-encoded data changed. Processing is now by default character per character instead of byte per byte on the underlying encoding. The tea: code that used things like pack("a*", $string) to peek through the encoding of a string will now just hand you back the original $string. No more snooping โจ. Packed strings can also get upgraded during processing when you store upgraded characters. Want the old behaviour back? use bytes and you're so back.
To stay consistent with pack(), the C0 in unpack() templates indicates the data is processed in character mode, i.e. character by character. On the contrary, U0 in unpack() indicates UTF-8 mode, where the packed string is processed in its UTF-8-encoded Unicode form, byte by byte. Heads up: this is reversed compared to perl 5.8.X โ but now it's consistent between pack() and unpack(), so slay.
Moreover, C0 and U0 can also be used in pack() templates to specify character and byte modes respectively.
And C0 / U0 sitting in the middle of a pack or unpack format now switch to the specified encoding mode, honoring parens grouping. Previously? Parens were just ignored. Rip. ๐ญ
Also, there's a new pack() character format, W, intended to replace the old C. C is kept for unsigned chars coded as bytes in the strings internal representation. W represents unsigned (logical) character values, which can be greater than 255. So it's more robust when dealing with potentially UTF-8-encoded data โ because C will wrap values outside the range 0..255 and not respect the string encoding.
In practice, that means pack formats are now encoding-neutral, except C.
For consistency, A in unpack() format now trims all Unicode whitespace from the end of the string. Before perl 5.9.2, it used to strip only the classical ASCII space characters. Upgrade moment fr. ๐ธ
๐ข Byte/character count feature in unpack() ๐ข
New unpack() template character bestie: . โ it returns the number of bytes or characters read so far. Which one? Depends on the selected encoding mode, see above ๐
.
๐ The $* and $# variables have been removed ๐
$*? Gone. It was deprecated in favor of the /s and /m regexp modifiers anyway.
The deprecated $# variable (output format for numbers)? Also gone.
And two new severe warnings dropped: "$#/$* is no longer supported". ๐
๐ช substr() lvalues are no longer fixed-length ๐ช
The lvalues returned by the three argument form of substr() used to be a "fixed length window" on the original string. In some cases this could cause surprising action at distance or other undefined behaviour ๐ญ. Now the length of the window adjusts itself to the length of the string assigned to it. Flexible era, we love to see it.
๐ต๏ธ Parsing of "-f _" ๐ต๏ธ
The identifier _ is now forced to be a bareword after a filetest operator. This solves a number of misparsing issues when a global _ subroutine is defined. ๐ซง
โจ ":unique" โจ
The :unique attribute has been made a no-op, since its current implementation was fundamentally flawed and not threadsafe. Bye bestie. ๐
๐ธ Effect of pragmas in eval ๐ธ
The compile-time value of the %^H hint variable can now propagate into eval("")uated code. This makes it more useful to implement lexical pragmas. Love that for us.
As a side-effect of this, the overloaded-ness of constants now propagates into eval("") too.
๐ chdir FOO ๐
A bareword argument to chdir() is now recognized as a file handle. Earlier releases interpreted the bareword as a directory name. (Gisle Aas)
๐ฆ Handling of .pmc files ๐ฆ
An old feature of perl was that before require or use look for a file with a .pm extension, they will first look for a similar filename with a .pmc extension. If this file is found, it will be loaded in place of any potentially existing file ending in a .pm extension.
Previously, .pmc files were loaded only if more recent than the matching .pm file. Starting with 5.9.4, they'll be always loaded if they exist. Periodt.
๐ $^V is now a "version" object instead of a v-string ๐
$^V can still be used with the %vd format in printf, but any character-level operations will now access the string representation of the version object and not the ordinals of a v-string. Expressions like substr($^V, 0, 2) or split //, $^V no longer work and must be rewritten. Sorry bestie ๐ญ.
๐ง @- and @+ in patterns ๐ง
The special arrays @- and @+ are no longer interpolated in regular expressions. (Sadahiro Tomoyuki)
๐ซง $AUTOLOAD can now be tainted ๐ซง
If you call a subroutine by a tainted name, and if it defers to an AUTOLOAD function, then $AUTOLOAD will be (correctly) tainted. (Rick Delaney)
๐ฅ Tainting and printf ๐ฅ
When perl is run under taint mode, printf() and sprintf() will now reject any tainted format argument. (Rafael Garcia-Suarez)
๐ undef and signal handlers ๐
Undefining or deleting a signal handler via undef $SIG{FOO} is now equivalent to setting it to 'DEFAULT'. (Rafael Garcia-Suarez)
๐ถ๏ธ strictures and dereferencing in defined() ๐ถ๏ธ
use strict 'refs' was ignoring taking a hard reference in an argument to defined(), as in:
use strict 'refs';
my $x = 'foo';
if (defined $$x) {...}
This now correctly produces the run-time error Can't use string as a SCALAR ref while "strict refs" in use.
defined @$foo and defined %$bar are now also subject to strict 'refs' โ that is, $foo and $bar shall be proper references there. (defined(@foo) and defined(%bar) are discouraged constructs anyway.) (Nicholas Clark)
๐ซ "(?p{})" has been removed ๐ซ
The regular expression construct (?p{}), which was deprecated in perl 5.8, has been removed. Use (??{}) instead. (Rafael Garcia-Suarez)
๐ Pseudo-hashes have been removed ๐
Support for pseudo-hashes has been removed from Perl 5.9. (The fields pragma remains here, but uses an alternate implementation.) ๐ฆ
๐ชฆ Removal of the bytecode compiler and of perlcc ๐ชฆ
perlcc, the byteloader and the supporting modules (B::C, B::CC, B::Bytecode, etc.) are no longer distributed with the perl sources. Those experimental tools have never worked reliably, and, due to the lack of volunteers to keep them in line with the perl interpreter developments, it was decided to remove them instead of shipping a broken version of those. The last version of those modules can be found with perl 5.9.4.
However the B compiler framework stays supported in the perl core, as with the more useful modules it has permitted (among others, B::Deparse and B::Concise). ๐
โ Removal of the JPL โ
The JPL (Java-Perl Lingo) has been removed from the perl sources tarball. Bye. ๐
๐ Recursive inheritance detected earlier ๐
Perl will now immediately throw an exception if you modify any package's @ISA in such a way that it would cause recursive inheritance.
Previously, the exception would not occur until Perl attempted to make use of the recursive inheritance while resolving a method or doing a $foo->isa($bar) lookup. Not anymore bestie, we're fast now.
๐ข warnings::enabled and warnings::warnif changed to favor users of modules ๐ข
The behaviour in 5.10.x favors the person using the module; the behaviour in 5.8.x favors the module writer.
Assume the following code:
main calls Foo::Bar::baz()
Foo::Bar inherits from Foo::Base
Foo::Bar::baz() calls Foo::Base::_bazbaz()
Foo::Base::_bazbaz() calls: warnings::warnif('substr', 'some warning message');
On 5.8.x, the code warns when Foo::Bar contains use warnings;. It does not matter if Foo::Base or main have warnings enabled โ to disable the warning one has to modify Foo::Bar.
On 5.10.0 and newer, the code warns when main contains use warnings;. It does not matter if Foo::Base or Foo::Bar have warnings enabled โ to disable the warning one has to modify main. ๐
๐ Removal of "package;" ("package" without arguments) ๐
The package; syntax that would let code switch out of any package (and thus require the use of either lexical or fully-qualified names) has been removed. Its semantics were never that clear and its implementation even less so. (It was previously deprecated in perl 5.8.0.) Iconic exit, honestly. ๐
๐งฉ Modules and Pragmata ๐งฉ
๐ฆ Upgrading individual core modules ๐ฆ
Even more core modules are now also available separately through the CPAN, bestie. If you wish to update one of these modules, you don't need to wait for a new perl release. From within the cpan shell, running the 'r' command will report on modules with upgrades available. See perldoc CPAN for more information.
๐ฎ Pragmata Changes ๐ฎ
feature
The new pragma feature is used to enable new features that might break old code. See "The "feature" pragma" above.
mro
This new pragma enables to change the algorithm used to resolve inherited methods. See "New Pragma, "mro"" above.
Scoping of the sort pragma
The sort pragma is now lexically scoped. Its effect used to be global. iconic behavior shift, fr fr โจ
Scoping of bignum, bigint, bigrat
The three numeric pragmas bignum, bigint and bigrat are now lexically scoped. (Tels)
base
The base pragma now warns if a class tries to inherit from itself. (Curtis "Ovid" Poe)
strict and warnings
strict and warnings will now complain loudly if they are loaded via incorrect casing (as in use Strict;). (Johan Vromans) not the sneaky lowercase energy anymore ๐ญ
version
The version module provides support for version objects.
warnings
The warnings pragma doesn't load Carp anymore. That means that code that used Carp routines without having loaded it at compile time might need to be adjusted; typically, the following (faulty) code won't work anymore, and will require parentheses to be added after the function name:
use warnings;
require Carp;
Carp::confess 'argh';
less
less now does something useful (or at least it tries to). In fact, it has been turned into a lexical pragma. So, in your modules, you can now test whether your users have requested to use less CPU, or less memory, less magic, or maybe even less fat. See less for more. (Joshua ben Jore) less is more, periodt ๐
๐ New modules ๐
encoding::warningsโ by Audrey Tang, is a module to emit warnings whenever an ASCII character string containing high-bit bytes is implicitly converted into UTF-8. It's a lexical pragma since Perl 5.9.4; on older perls, its effect is global.Module::CoreListโ by Richard Clamp, is a small handy module that tells you what versions of core modules ship with any versions of Perl 5. It comes with a command-line frontend,corelist.Math::BigInt::FastCalcโ is an XS-enabled, and thus faster, version ofMath::BigInt::Calc.Compress::Zlibโ is an interface to the zlib compression library. It comes with a bundled version of zlib, so having a working zlib is not a prerequisite to install it. It's used byArchive::Tar(see below).IO::Zlibโ is anIO::-style interface toCompress::Zlib.Archive::Tarโ is a module to manipulatetararchives.Digest::SHAโ is a module used to calculate many types of SHA digests, has been included for SHA support in the CPAN module.ExtUtils::CBuilderandExtUtils::ParseXSโ have been added.Hash::Util::FieldHashโ by Anno Siegel, has been added. This module provides support for field hashes: hashes that maintain an association of a reference with a value, in a thread-safe garbage-collected way. Such hashes are useful to implement inside-out objects.Module::Buildโ by Ken Williams, has been added. It's an alternative toExtUtils::MakeMakerto build and install perl modules.Module::Loadโ by Jos Boumans, has been added. It provides a single interface to load Perl modules and.plfiles.Module::Loadedโ by Jos Boumans, has been added. It's used to mark modules as loaded or unloaded.Package::Constantsโ by Jos Boumans, has been added. It's a simple helper to list all constants declared in a given package.Win32API::Fileโ by Tye McQueen, has been added (for Windows builds). This module provides low-level access to Win32 system API calls for files/dirs.Locale::Maketext::Simpleโ needed by CPANPLUS, is a simple wrapper aroundLocale::Maketext::Lexicon. Note thatLocale::Maketext::Lexiconisn't included in the perl core; the behaviour ofLocale::Maketext::Simplegracefully degrades when the later isn't present.Params::Checkโ implements a generic input parsing/checking mechanism. It is used by CPANPLUS.Term::UIโ simplifies the task to ask questions at a terminal prompt.Object::Accessorโ provides an interface to create per-object accessors.Module::Pluggableโ is a simple framework to create modules that accept pluggable sub-modules.Module::Load::Conditionalโ provides simple ways to query and possibly load installed modules.Time::Pieceโ provides an object oriented interface to time functions, overriding the built-inslocaltime()andgmtime().IPC::Cmdโ helps to find and run external commands, possibly interactively.File::Fetchโ provide a simple generic file fetching mechanism.Log::MessageandLog::Message::Simpleโ are used by the log facility ofCPANPLUS.Archive::Extractโ is a generic archive extraction mechanism for.tar(plain, gzipped or bzipped) or.zipfiles.CPANPLUSโ provides an API and a command-line tool to access the CPAN mirrors.Pod::Escapesโ provides utilities that are useful in decoding PodE<...>sequences.Pod::Simpleโ is now the backend for several of the Pod-related modules included with Perl.
๐ ๏ธ Selected Changes to Core Modules ๐ ๏ธ
Attribute::Handlers
Attribute::Handlers can now report the caller's file and line number. (David Feldman)
All interpreted attributes are now passed as array references. (Damian Conway)
B::Lint
B::Lint is now based on Module::Pluggable, and so can be extended with plugins. (Joshua ben Jore)
B
It's now possible to access the lexical pragma hints (%^H) by using the method B::COP::hints_hash(). It returns a B::RHE object, which in turn can be used to get a hash reference via the method B::RHE::HASH(). (Joshua ben Jore)
Thread
As the old 5005thread threading model has been removed, in favor of the ithreads scheme, the Thread module is now a compatibility wrapper, to be used in old code only. It has been removed from the default list of dynamic extensions.
๐งฐ Utility Changes ๐งฐ
perl -d
The Perl debugger can now save all debugger commands for sourcing later; notably, it can now emulate stepping backwards, by restarting and rerunning all bar the last command from a saved command history.
It can also display the parent inheritance tree of a given class, with the i command.
ptar
ptar is a pure perl implementation of tar that comes with Archive::Tar.
ptardiff
ptardiff is a small utility used to generate a diff between the contents of a tar archive and a directory tree. Like ptar, it comes with Archive::Tar.
shasum
shasum is a command-line utility, used to print or to check SHA digests. It comes with the new Digest::SHA module.
corelist
The corelist utility is now installed with perl (see "New modules" above).
h2ph and h2xs
h2ph and h2xs have been made more robust with regard to "modern" C code.
h2xs implements a new option --use-xsloader to force use of XSLoader even in backwards compatible modules.
The handling of authors' names that had apostrophes has been fixed.
Any enums with negative values are now skipped.
perlivp
perlivp no longer checks for *.ph files by default. Use the new -a option to run all tests.
find2perl
find2perl now assumes -print as a default action. Previously, it needed to be specified explicitly.
Several bugs have been fixed in find2perl, regarding -exec and -eval. Also the options -path, -ipath and -iname have been added.
config_data
config_data is a new utility that comes with Module::Build. It provides a command-line interface to the configuration of Perl modules that use Module::Build's framework of configurability (that is, *::ConfigData modules that contain local configuration information for their parent modules.)
cpanp
cpanp, the CPANPLUS shell, has been added. (cpanp-run-perl, a helper for CPANPLUS operation, has been added too, but isn't intended for direct use).
cpan2dist
cpan2dist is a new utility that comes with CPANPLUS. It's a tool to create distributions (or packages) from CPAN modules.
pod2html
The output of pod2html has been enhanced to be more customizable via CSS. Some formatting problems were also corrected. (Jari Aalto)
๐ New Documentation ๐
The perlpragma manpage documents how to write one's own lexical pragmas in pure Perl (something that is possible starting with 5.9.4).
The new perlglossary manpage is a glossary of terms used in the Perl documentation, technical and otherwise, kindly provided by O'Reilly Media, Inc.
The perlreguts manpage, courtesy of Yves Orton, describes internals of the Perl regular expression engine.
The perlreapi manpage describes the interface to the perl interpreter used to write pluggable regular expression engines (by รvar Arnfjรถrรฐ Bjarmason).
The perlunitut manpage is a tutorial for programming with Unicode and string encodings in Perl, courtesy of Juerd Waalboer.
A new manual page, perlunifaq (the Perl Unicode FAQ), has been added (Juerd Waalboer).
The perlcommunity manpage gives a description of the Perl community on the Internet and in real life. (Edgar "Trizor" Bering)
The CORE manual page documents the CORE:: namespace. (Tels)
The long-existing feature of /(?{...})/ regexps setting $_ and pos() is now documented.
โจ Performance Enhancements โจ
ok bestie, buckle UP, this is the glow-up era ๐ perl got so much faster and it's giving main character energy.
๐๏ธ In-place sorting
Sorting arrays in place (@a = sort @a) is now optimized to avoid making a temporary copy of the array. no dupe, no drama, just vibes ๐ธ
Likewise, reverse sort ... is now optimized to sort in reverse, avoiding the generation of a temporary intermediate list. iconic behaviour tbh.
๐ง Lexical array access
Access to elements of lexical arrays via a numeric constant between 0 and 255 is now faster. (This used to be only the case for global arrays.) lowkey a niche win but we love it โจ
๐ค XS-assisted SWASHGET
Some pure-perl code that perl was using to retrieve Unicode properties and transliteration mappings has been reimplemented in XS. speed ๐โ๏ธ๐จ
๐ Constant subroutines
The interpreter internals now support a far more memory efficient form of inlineable constants. Storing a reference to a constant value in a symbol table is equivalent to a full typeglob referencing a constant subroutine, but using about 400 bytes less memory. This proxy constant subroutine is automatically upgraded to a real typeglob with subroutine if necessary. The approach taken is analogous to the existing space optimisation for subroutine stub declarations, which are stored as plain scalars in place of the full typeglob.
Several of the core modules have been converted to use this feature for their system dependent constants โ as a result use POSIX; now takes about 200K less memory. 200K!! for free!! ๐
๐ฉ PERL_DONT_CREATE_GVSV
The new compilation flag PERL_DONT_CREATE_GVSV, introduced as an option in perl 5.8.8, is turned on by default in perl 5.9.3. It prevents perl from creating an empty scalar with every new typeglob. See perl589delta for details.
๐ชถ Weak references are cheaper
Weak reference creation is now O(1) rather than O(n), courtesy of Nicholas Clark. Weak reference deletion remains O(n), but if deletion only happens at program exit, it may be skipped completely. okay but the free exit skip?? chef's kiss ๐
๐ sort() enhancements
Salvador Fandiรฑo provided improvements to reduce the memory usage of sort and to speed up some cases. thank you Salvador, we appreciate you ๐ซถ
๐๏ธ Memory optimisations
Several internal data structures (typeglobs, GVs, CVs, formats) have been restructured to use less memory. (Nicholas Clark) decluttering arc, honestly โจ
๐ง UTF-8 cache optimisation
The UTF-8 caching code is now more efficient, and used more often. (Nicholas Clark)
๐ช Sloppy stat on Windows
On Windows, perl's stat() function normally opens the file to determine the link count and update attributes that may have been changed through hard links. Setting ${^WIN32_SLOPPY_STAT} to a true value speeds up stat() by not performing this operation. (Jan Dubois)
๐งต Regular expressions optimisations
๐ Engine de-recursivised
The regular expression engine is no longer recursive, meaning that patterns that used to overflow the stack will either die with useful explanations, or run to completion, which, since they were able to blow the stack before, will likely take a very long time to happen. If you were experiencing the occasional stack overflow (or segfault) and upgrade to discover that now perl apparently hangs instead, look for a degenerate regex. (Dave Mitchell)
fr fr, "hangs instead" is not a bug, it's your regex being a menace ๐ go find the degenerate one.
๐ก Single char char-classes treated as literals
Classes of a single character are now treated the same as if the character had been used as a literal, meaning that code that uses char-classes as an escaping mechanism will see a speedup. (Yves Orton)
๐ณ Trie optimisation of literal string alternations
Alternations, where possible, are optimised into more efficient matching structures. String literal alternations are merged into a trie and are matched simultaneously. This means that instead of O(N) time for matching N alternations at a given point, the new code performs in O(1) time. A new special variable, ${^RE_TRIE_MAXBUF}, has been added to fine-tune this optimization. (Yves Orton)
Note: Much code exists that works around perl's historic poor performance on alternations. Often the tricks used to do so will disable the new optimisations. Hopefully the utility modules used for this purpose will be educated about these new optimisations. ๐ like bestie, the old workarounds are fighting the new glow-up, we gotta let them go.
๐ฏ Aho-Corasick start-point optimisation
When a pattern starts with a trie-able alternation and there aren't better optimisations available, the regex engine will use Aho-Corasick matching to find the start point. (Yves Orton)
๐ ๏ธ Installation and Configuration Improvements ๐ ๏ธ
โ๏ธ Configuration improvements
๐ช -Dusesitecustomize
Run-time customization of @INC can be enabled by passing the -Dusesitecustomize flag to Configure. When enabled, this will make perl run $sitelibexp/sitecustomize.pl before anything else. This script can then be set up to add additional entries to @INC. customizing your @INC at runtime?? so real ๐
๐ฆ Relocatable installations
There is now Configure support for creating a relocatable perl tree. If you Configure with -Duserelocatableinc, then the paths in @INC (and everything else in %Config) can be optionally located via the path of the perl executable.
That means that, if the string .../ is found at the start of any path, it's substituted with the directory of $^X. So, the relocation can be configured on a per-directory basis, although the default with -Duserelocatableinc is that everything is relocated. The initial install is done to the original configured prefix.
๐งต strlcat() and strlcpy()
The configuration process now detects whether strlcat() and strlcpy() are available. When they are not available, perl's own version is used (from Russ Allbery's public domain implementation). Various places in the perl interpreter now use them. (Steve Peters)
๐ d_pseudofork and d_printf_format_null
A new configuration variable, available as $Config{d_pseudofork} in the Config module, has been added, to distinguish real fork() support from fake pseudofork used on Windows platforms.
A new configuration variable, d_printf_format_null, has been added, to see if printf-like formats are allowed to be NULL.
โ Configure help
Configure -h has been extended with the most commonly used options. finally, help that actually helps ๐ญ
๐จ Compilation improvements
๐ง๐ค๐ง Parallel build
Parallel makes should work properly now, although there may still be problems if make test is instructed to run in parallel.
heads up bestie โ make test in parallel is still a lil sus, don't come for me.
๐ข Borland's compilers support
Building with Borland's compilers on Win32 should work more smoothly. In particular Steve Hay has worked to side step many warnings emitted by their compilers and at least one C compiler internal error. the way he dodged an internal compiler error?? legend ๐ซถ
๐ฅ Static build on Windows
Perl extensions on Windows now can be statically built into the Perl DLL.
Also, it's now possible to build a perl-static.exe that doesn't depend on the Perl DLL on Win32. See the Win32 makefiles for details. (Vadim Konovalov)
๐ ppport.h files
All ppport.h files in the XS modules bundled with perl are now autogenerated at build time. (Marcus Holland-Moritz)
โโ C++ compatibility
Efforts have been made to make perl and the core XS modules compilable with various C++ compilers (although the situation is not perfect with some of the compilers on some of the platforms tested.)
๐ช Support for Microsoft 64-bit compiler
Support for building perl with Microsoft's 64-bit compiler has been improved. (ActiveState)
๐จ Visual C++
Perl can now be compiled with Microsoft Visual C++ 2005 (and 2008 Beta 2).
๐ช Win32 builds
All win32 builds (MS-Win, WinCE) have been merged and cleaned up. tidy โจ
๐ฒ Installation improvements
๐ Module auxiliary files
README files and changelogs for CPAN modules bundled with perl are no longer installed.
๐ New Or Improved Platforms
Perl has been reported to work on Symbian OS. See perlsymbian for more information.
Many improvements have been made towards making Perl work correctly on z/OS.
Perl has been reported to work on DragonFlyBSD and MidnightBSD.
Perl has also been reported to work on NexentaOS ( http://www.gnusolaris.org/ ).
The VMS port has been improved. See perlvms.
Support for Cray XT4 Catamount/Qk has been added. See hints/catamount.sh in the source code distribution for more information.
Vendor patches have been merged for RedHat and Gentoo.
DynaLoader::dl_unload_file() now works on Windows. ๐ช๐
๐ Selected Bug Fixes ๐
strictures in regexp-eval blocks
okay so this is lowkey embarrassing but "strict" just... wasn't in effect inside regexp-eval blocks, like /(?{...})/. bestie. it is now. โจ
Calling CORE::require()
CORE::require() and CORE::do() were always being parsed as plain old require() and do() whenever they'd been overridden. fixed now, thank u. ๐ซถ
Subscripts of slices
you can now use a non-arrowed form for chained subscripts after a list slice, like this:
({foo => "bar"})[0]{foo}
this used to be a straight-up syntax error, you had to write the ->. iconic that it just works now. ๐
no warnings 'category' works correctly with -w
ngl this one was a menace. previously, when you ran with warnings enabled globally via -w, selectively disabling specific warning categories would actually turn off all warnings. which is not it. this is fixed now โ no warnings 'io'; will only turn off warnings in the io class. before, it would erroneously turn off everything. ๐
threads improvements
several memory leaks in ithreads got closed, and ithreads were made less memory-intensive. slay.
threads is now a dual-life module, also available on CPAN. it's been expanded in many ways: a kill() method is available for thread signalling, and you can get thread status, or the list of running or joinable threads.
a new threads->exit() method is used to exit from the application (this is the default for the main thread) or from the current thread only (this is the default for all other threads). on the other hand, the exit() built-in now always causes the whole application to terminate. (Jerry D. Hedden) ๐งต
chr() and negative values
chr() on a negative value now gives "\x{FFFD}", the Unicode replacement character โ unless the bytes pragma is in effect, in which case the low eight bits of the value are used. ๐ธ
PERL5SHELL and tainting
on Windows, the PERL5SHELL environment variable is now checked for taintedness. (Rafael Garcia-Suarez)
Using *FILE{IO}
stat() and -X filetests now treat *FILE{IO} filehandles like *FILE filehandles. (Steve Peters)
Overloading and reblessing
overloading now works when references are reblessed into another class. internally, this got implemented by moving the flag for "overloading" from the reference to the referent, which logically is where it should always have been. (Nicholas Clark) โจ
Overloading and UTF-8
a few bugs related to UTF-8 handling with objects that have stringification overloaded have been fixed. (Nicholas Clark)
eval memory leaks fixed
traditionally, eval 'syntax error' has leaked badly. many (but not all) of these leaks have now been eliminated or reduced. (Dave Mitchell)
Random device on Windows
in previous versions, perl would read the file /dev/urandom if it existed when seeding its random number generator. that file is unlikely to exist on Windows, and if it did would probably not contain appropriate data, so perl no longer tries to read it on Windows. (Alex Davies) ๐ฒ
PERLIO_DEBUG
the PERLIO_DEBUG environment variable no longer has any effect for setuid scripts and for scripts run with -T.
moreover, with a thread-enabled perl, using PERLIO_DEBUG could lead to an internal buffer overflow. this has been fixed. ๐ฎโ๐จ
PerlIO::scalar and read-only scalars
PerlIO::scalar will now prevent writing to read-only scalars. moreover, seek() is now supported with PerlIO::scalar-based filehandles, the underlying string being zero-filled as needed. (Rafael, Jarkko Hietaniemi)
study() and UTF-8
study() never worked for UTF-8 strings, but could lead to false results. it's now a no-op on UTF-8 data. (Yves Orton)
Critical signals
the signals SIGILL, SIGBUS and SIGSEGV are now always delivered in an "unsafe" manner โ contrary to other signals, that are deferred until the perl interpreter reaches a reasonably stable state; see "Deferred Signals (Safe Signals)" in perlipc. (Rafael) ๐จ
@INC-hook fix
when a module or a file is loaded through an @INC-hook, and when this hook has set a filename entry in %INC, __FILE__ is now set for this module according to the contents of that %INC entry. (Rafael)
-t switch fix
the -w and -t switches can now be used together without messing up which categories of warnings are activated. (Rafael)
Duping UTF-8 filehandles
duping a filehandle which has the :utf8 PerlIO layer set will now properly carry that layer on the duped filehandle. (Rafael)
Localisation of hash elements
localizing a hash element whose key was given as a variable didn't work correctly if the variable was changed while the local() was in effect (as in local $h{$x}; ++$x). (Bo Lindbergh)
๐ฃ๏ธ New or Changed Diagnostics ๐ข
Use of uninitialized value
perl will now try to tell you the name of the variable (if any) that was undefined. so helpful fr fr. ๐ฅน
Deprecated use of my() in false conditional
a new deprecation warning, Deprecated use of my() in false conditional, has been added, to warn against the use of the dubious and deprecated construct
my $x if 0;
see perldiag. use state variables instead. ๐
!=~ should be !~
a new warning, !=~ should be !~, is emitted to prevent this misspelling of the non-matching operator.
Newline in left-justified string
the warning Newline in left-justified string has been removed. bye bestie ๐
Too late for "-T" option
the error Too late for "-T" option has been reformulated to be more descriptive.
"%s" variable %s masks earlier declaration
this warning is now emitted in more consistent cases; in short, when one of the declarations involved is a my variable:
my $x; my $x; # warns
my $x; our $x; # warns
our $x; my $x; # warns
on the other hand, the following:
our $x; our $x;
now gives a "our" variable %s redeclared warning.
readdir()/closedir()/etc. attempted on invalid dirhandle
these new warnings are now emitted when a dirhandle is used but is either closed or not really a dirhandle.
Opening dirhandle/filehandle %s also as a file/directory
two deprecation warnings have been added: (Rafael)
Opening dirhandle %s also as a file
Opening filehandle %s also as a directory
Use of -P is deprecated
perl's command-line switch -P is now deprecated.
v-string in use/require is non-portable
perl will warn you against potential backwards compatibility problems with the use VERSION syntax.
perl -V
perl -V has several improvements, making it more useable from shell scripts to get the value of configuration variables. see perlrun for details.
๐ ๏ธ Changed Internals ๐ง
in general, the source code of perl has been refactored, tidied up, and optimized in many places. also, memory management and allocation has been improved in several points. glow up โจ
when compiling the perl core with gcc, as many gcc warning flags are turned on as is possible on the platform. (this quest for cleanliness doesn't extend to XS code because we cannot guarantee the tidiness of code we didn't write.) similar strictness flags have been added or tightened for various other C compilers.
Reordering of SVt_* constants
the relative ordering of constants that define the various types of SV have changed; in particular, SVt_PVGV has been moved before SVt_PVLV, SVt_PVAV, SVt_PVHV and SVt_PVCV. this is unlikely to make any difference unless you have code that explicitly makes assumptions about that ordering. (the inheritance hierarchy of B::* objects has been changed to reflect this.) ๐
Elimination of SVt_PVBM
related to this, the internal type SVt_PVBM has been removed. this dedicated type of SV was used by the index operator and parts of the regexp engine to facilitate fast Boyer-Moore matches. its use internally has been replaced by SVs of type SVt_PVGV.
New type SVt_BIND
a new type SVt_BIND has been added, in readiness for the project to implement Perl 6 on 5. there deliberately is no implementation yet, and they cannot yet be created or destroyed.
Removal of CPP symbols
the C preprocessor symbols PERL_PM_APIVERSION and PERL_XS_APIVERSION, which were supposed to give the version number of the oldest perl binary-compatible (resp. source-compatible) with the present one, were not used, and sometimes had misleading values. they have been removed.
Less space is used by ops
the BASEOP structure now uses less space. the op_seq field has been removed and replaced by a single bit bit-field op_opt. op_type is now 9 bits long. (consequently, the B::OP class doesn't provide an seq method anymore.)
New parser
perl's parser is now generated by bison (it used to be generated by byacc.) as a result, it seems to be a bit more robust.
also, Dave Mitchell improved the lexer debugging output under -DT.
Use of const
Andy Lester supplied many improvements to determine which function parameters and local variables could actually be declared const to the C compiler. Steve Peters provided new *_set macros and reworked the core to use these rather than assigning to macros in LVALUE context.
Mathoms
a new file, mathoms.c, has been added. it contains functions that are no longer used in the perl core, but that remain available for binary or source compatibility reasons. however, those functions will not be compiled in if you add -DNO_MATHOMS in the compiler flags.
AvFLAGS has been removed
the AvFLAGS macro has been removed.
av_* changes
the av_*() functions, used to manipulate arrays, no longer accept null AV* parameters.
$^H and %^H
the implementation of the special variables $^H and %^H has changed, to allow implementing lexical pragmas in pure Perl.
B:: modules inheritance changed
the inheritance hierarchy of B:: modules has changed; B::NV now inherits from B::SV (it used to inherit from B::IV).
Anonymous hash and array constructors
the anonymous hash and array constructors now take 1 op in the optree instead of 3, now that pp_anonhash and pp_anonlist return a reference to a hash/array when the op is flagged with OPf_SPECIAL. (Nicholas Clark) ๐
๐ซ KNOWN PROBLEMS ๐ซ
Okay bestie, gather round, because there are still some little gremlins living in here and we're gonna name them by name. ๐
- There's still a remaining problem in the implementation of the lexical
$_: it does not work inside/(?{...})/blocks. (See the TODO test int/op/mydef.t.) - Stacked filetest operators won't work when the
filetestpragma is in effect, because they rely on thestat()buffer_being populated, andfiletestbypassesstat().
๐ UTF-8 problems
The handling of Unicode still is unclean in several places, where it's dependent on whether a string is internally flagged as UTF-8. This will be made more consistent in perl 5.12, but that won't be possible without a certain amount of backwards incompatibility. So likeโฆ glow-up incoming, but somebody's gotta get their heart broken for it. ๐ญ
๐ง PLATFORM SPECIFIC PROBLEMS ๐ง
When compiled with g++ and thread support on Linux, it's reported that the $! stops working correctly. This is related to the fact that the glibc provides two strerror_r(3) implementations, and perl selects the wrong one. Not her fault, fr fr, but also. Ma'am. ๐
๐ REPORTING BUGS ๐
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/rt3/ . There may also be information at http://www.perl.org/ , the Perl Home Page. โจ
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 analysed by the Perl porting team. ๐
Okay real talk bestie: a tiny-but-sufficient test case is the whole assignment. Nobody can debug "it's broken" with zero context, and you deserve a fix, so give the porting team something they can actually run. ๐
๐ SEE ALSO ๐
- The
Changesfile and theperl590deltatoperl595deltaman pages for exhaustive details on what changed. - The
INSTALLfile for how to build Perl. - The
READMEfile for general stuff. - The
ArtisticandCopyingfiles for copyright information.
And that's a wrap on this whole delta, bestie โ you ate. ๐ This page is from perl v5.42.3, dated 2026-08-03, and it's the PERL5100DELTA(1) manual page. Go forth and be iconic with your 5.10.0 knowledge. ๐โจ๐ฆ
๐ฆ where this page comes from
- fedora 43: perl-doc 5.42.3-524.fc43 ยท (GPL-1.0-or-later OR Artistic-1.0-Perl) AND Unicode-3.0 AND LicenseRef-Fedora-UltraPermissive
- fedora 44: perl-doc 5.42.3-525.fc44 ยท (GPL-1.0-or-later OR Artistic-1.0-Perl) AND Unicode-3.0 AND LicenseRef-Fedora-UltraPermissive
- ๐ girlified by deepseek-ai/DeepSeek-V4.1-Flash on : a language model's rewrite of the original, under its terms