perlexperiment

PERLEXPERIMENT(1)      Perl Programmers Reference Guide      PERLEXPERIMENT(1)

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
       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]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=119317>.

       Pluggable keywords
               The ticket for this feature is [perl #119455]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=119455>.

               See "PL_keyword_plugin" in perlapi for the mechanism.

               Introduced in Perl 5.11.2

       Regular Expression Set Operations
               Introduced in Perl 5.18

               The ticket for this feature is [perl #119451]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=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]
               <https://rt.perl.org/Ticket/Display.html?id=121481>.

       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]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=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]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=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

       The <:win32> IO pseudolayer
               The ticket for this feature is [perl #119453]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=119453>.

               See also perlrun

       Declaring a reference to a variable
               Introduced in Perl 5.26.0

               Using this feature triggers warnings in the category
               "experimental::declared_refs".

               The ticket for this feature is [perl #128654]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=128654>.

               See also: "Declaring a Reference to a Variable" in perlref

       There is an "installhtml" target in the Makefile.
               The ticket for this feature is [perl #116487]
               <https://rt.perl.org/rt3/Ticket/Display.html?id=116487>.

       Unicode in Perl on EBCDIC
       Script runs
               Introduced in Perl 5.28.0

               Using this feature triggers warnings in the category
               "experimental::script_run".

               See also: "Script Runs" in perlre

       Alphabetic assertions
               Introduced in Perl 5.28.0

               Using this feature triggers warnings in the category
               "experimental::alpha_assertions".

               See also: "Extended Patterns" in perlre.

   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

       Postfix dereference syntax
               Introduced in Perl 5.20.0

               Accepted in Perl 5.24.0

       Lexical subroutines
               Introduced in Perl 5.18.0

               Accepted in Perl 5.26.0

       String- and number-specific bitwise operators
               Introduced in Perl 5.22.0

               Accepted in Perl 5.28.0

   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 Perl 5.11.2

               Removed in Perl 5.11.3

       Lexical $_
               Using this feature triggered warnings in the category
               "experimental::lexical_topic".

               Introduced in Perl 5.10.0

               Removed in Perl 5.24.0

       Array and hash container functions accept references
               Using this feature triggered warnings in the category
               "experimental::autoderef".

               Superseded by "Postfix dereference syntax".

               Introduced in Perl 5.14.0

               Removed in Perl 5.24.0

       "our" can have an experimental optional attribute "unique"
               Introduced in Perl 5.8.0

               Deprecated in Perl 5.10.0

               Removed in Perl 5.28.0

SEE ALSO
       For a complete list of features check feature.

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

       Sebastien 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.

perl v5.30.0                      2023-11-23                 PERLEXPERIMENT(1)