CONTENTS

• NAME
• DESCRIPTION
  • Current experiments
  • Accepted features
  • Removed features
• SEE ALSO
• AUTHORS
• COPYRIGHT
• LICENSE

#NAME

perlexperiment - A listing of experimental features in Perl

#DESCRIPTION

This document lists the current and past experimental features in the perl core. Although all of these are documented with their appropriate topics, this succinct listing gives you an overview and basic facts about their status.

So far we've merely tried to find and list the experimental features and infer their inception, versions, etc. There's a lot of speculation here.

#Current experiments

#our can now have an experimental optional attribute unique

Introduced in Perl 5.8.0

Deprecated in Perl 5.10.0

The ticket for this feature is [perl #119313].

#Smart match (~~)

Introduced in Perl 5.10.0

Modified in Perl 5.10.1, 5.12.0

Using this feature triggers warnings in the category experimental::smartmatch.

The ticket for this feature is [perl #119317].

#Lexical $_

Introduced in Perl 5.10.0

Using this feature triggers warnings in the category experimental::lexical_topic.

The ticket for this feature is [perl #119315].

#Pluggable keywords

The ticket for this feature is [perl #119455].

See "PL_keyword_plugin" in perlapi for the mechanism.

Introduced in: Perl 5.11.2

#Array and hash container functions accept references

Introduced in Perl 5.14.0

The ticket for this feature is [perl #119437].

#Lexical subroutines

Introduced in: Perl 5.18

See also: "Lexical Subroutines" in perlsub

Using this feature triggers warnings in the category experimental::lexical_subs.

The ticket for this feature is [perl #120085].

#Regular Expression Set Operations

Introduced in: Perl 5.18

The ticket for this feature is [perl #119451].

See also: "Extended Bracketed Character Classes" in perlrecharclass

Using this feature triggers warnings in the category experimental::regex_sets.

#Subroutine signatures

Introduced in Perl 5.20.0

Using this feature triggers warnings in the category experimental::signatures.

The ticket for this feature is [perl #121481].

#Postfix dereference syntax

Introduced in Perl 5.20.0

Using this feature triggers warnings in the category experimental::postderef.

The ticket for this feature is [perl #120162].

#Aliasing via reference

Introduced in Perl 5.22.0

Using this feature triggers warnings in the category experimental::refaliasing.

The ticket for this feature is [perl #122947].

See also: "Assigning to References" in perlref

#The "const" attribute

Introduced in Perl 5.22.0

Using this feature triggers warnings in the category experimental::const_attr.

The ticket for this feature is [perl #123630].

See also: "Constant Functions" in perlsub

#use re 'strict';

Introduced in Perl 5.22.0

Using this feature triggers warnings in the category experimental::re_strict.

See "'strict' mode" in re

#String- and number-specific bitwise operators

Introduced in: Perl 5.22.0

See also: "Bitwise String Operators" in perlop

Using this feature triggers warnings in the category experimental::bitwise.

The ticket for this feature is [perl #123707].

#The <:win32> IO pseudolayer

The ticket for this feature is [perl #119453].

See also perlrun

#There is an installhtml target in the Makefile.

The ticket for this feature is [perl #116487].

#Unicode in Perl on EBCDIC

#Accepted features

These features were so wildly successful and played so well with others that we decided to remove their experimental status and admit them as full, stable features in the world of Perl, lavishing all the benefits and luxuries thereof. They are also awarded +5 Stability and +3 Charisma.

#64-bit support

Introduced in Perl 5.005

#die accepts a reference

Introduced in Perl 5.005

#DB module

Introduced in Perl 5.6.0

See also perldebug, perldebtut

#Weak references

Introduced in Perl 5.6.0

#Internal file glob

Introduced in Perl 5.6.0

#fork() emulation

Introduced in Perl 5.6.1

See also perlfork

#-Dusemultiplicity -Duseithreads

Introduced in Perl 5.6.0

Accepted in Perl 5.8.0

#Support for long doubles

Introduced in Perl 5.6.0

Accepted in Perl 5.8.1

#The \N regex character class

The \N character class, not to be confused with the named character sequence \N{NAME}, denotes any non-newline character in a regular expression.

Introduced in Perl 5.12

Exact version of acceptance unclear, but no later than Perl 5.18.

#(?{code}) and (??{ code })

Introduced in Perl 5.6.0

Accepted in Perl 5.20.0

See also perlre

#Linux abstract Unix domain sockets

Introduced in Perl 5.9.2

Accepted before Perl 5.20.0. The Socket library is now primarily maintained on CPAN, rather than in the perl core.

See also Socket

#Lvalue subroutines

Introduced in Perl 5.6.0

Accepted in Perl 5.20.0

See also perlsub

#Backtracking control verbs

(*ACCEPT)

Introduced in: Perl 5.10

Accepted in Perl 5.20.0

#The <:pop> IO pseudolayer

See also perlrun

Accepted in Perl 5.20.0

#\s in regexp matches vertical tab

Accepted in Perl 5.22.0

#Removed features

These features are no longer considered experimental and their functionality has disappeared. It's your own fault if you wrote production programs using these features after we explicitly told you not to (see perlpolicy).

#5.005-style threading

Introduced in Perl 5.005

Removed in Perl 5.10

#perlcc

Introduced in Perl 5.005

Moved from Perl 5.9.0 to CPAN

#The pseudo-hash data type

Introduced in Perl 5.6.0

Removed in Perl 5.9.0

#GetOpt::Long Options can now take multiple values at once (experimental)

Getopt::Long upgraded to version 2.35

Removed in Perl 5.8.8

#Assertions

The -A command line switch

Introduced in Perl 5.9.0

Removed in Perl 5.9.5

#Test::Harness::Straps

Moved from Perl 5.10.1 to CPAN

#legacy

The experimental legacy pragma was swallowed by the feature pragma.

Introduced in: 5.11.2

Removed in: 5.11.3

#SEE ALSO

For a complete list of features check feature.

#AUTHORS

brian d foy <brian.d.foy@gmail.com>

Sébastien Aperghis-Tramoni <saper@cpan.org>

#COPYRIGHT

Copyright 2010, brian d foy <brian.d.foy@gmail.com>

#LICENSE

You can use and redistribute this document under the same terms as Perl itself.

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