- NAME
- DESCRIPTION
  - Current experiments
  - Accepted features
  - Removed features
- 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

-Dusemultiplicity -Duseithreads

  Introduced in Perl 5.6.0

Long Doubles Still Don't Work In Solaris

  Introduced in Perl 5.7.0

`our` can now have an experimental optional attribute `unique`

  Introduced in Perl 5.8.0

  Deprecated in Perl 5.10.0

Linux abstract Unix domain sockets

  Introduced in Perl 5.9.2

  See also Socket

Pod::HTML2Pod
Pod::PXML
The <:pop> IO pseudolayer

  See also perlrun

The <:win32> IO pseudolayer

  See also perlrun

MLDBM

  See also perldsc

internal functions with M flag

  See also perlguts

lex_start API

  Introduced in Perl 5.13.7

internal API for `%^H`

  Introduced in Perl 5.13.7

  See also `cophh_` in perlapi.

alloccopstash

  Introduced in Perl 5.18.0

av_create_and_push
av_create_and_unshift_one
av_create_and_unshift_one
cop_store_label

  Introduced in Perl 5.16.0

PL_keyword_plugin
gv_fetchmethod_*_flags

  Introduced in Perl 5.16.0

hv_iternext_flags
lex_bufutf8
lex_discard_to
lex_grow_linestr
lex_next_chunk
lex_peek_unichar
lex_read_space
lex_read_to
lex_read_unichar
lex_stuff_pv
lex_stuff_pvn
lex_stuff_pvs
lex_stuff_sv
lex_unstuff
op_scope
op_lvalue
parse_fullstmt
parse_stmtseq
PL_parser->bufend
PL_parser->bufptr
PL_parser->linestart
PL_parser->linestr
Perl_signbit
pad_findmy
sv_utf8_decode
sv_utf8_downgrade
bytes_from_utf8
bytes_to_utf8
utf8_to_bytes
Lvalue subroutines

  Introduced in Perl 5.6.0

  See also perlsub

There is an `installhtml` target in the Makefile.
Unicode in Perl on EBCDIC
`(?{code})`

  See also perlre

`(??{ code })`

  See also perlre

Smart match (`~~`)

  Introduced in Perl 5.10.0

  Modified in Perl 5.10.1, 5.12.0

Lexical `$_`

  Introduced in Perl 5.10.0

Backtracking control verbs

  `(*ACCEPT)`

  Introduced in: Perl 5.10

  See also: "Special Backtracking Control Verbs" in perlre

Code expressions, conditional expressions, and independent expressions in regexes
gv_try_downgrade

  See also perlintern

Experimental Support for Sun Studio Compilers for Linux OS

  See also perllinux

Pluggable keywords

  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

Lexical subroutines

  Introduced in: Perl 5.18

  See also: "Lexical Subroutines" in perlsub

Regular Expression Set Operations

  Introduced in: Perl 5.18

  See also: "Extended Bracketed Character Classes" in perlrecharclass

## 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.

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

fork() emulation

  Introduced in Perl 5.6.1

  See also perlfork

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

die accepts a reference

  Introduced in Perl 5.005

64-bit support

  Introduced in Perl 5.005

## 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).

`legacy`

  The experimental `legacy` pragma was swallowed by the `feature` pragma.

  Introduced in: 5.11.2

  Removed in: 5.11.3

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

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

  `Getopt::Long` upgraded to version 2.35

  Removed in Perl 5.8.8

The pseudo-hash data type

  Introduced in Perl 5.6.0

  Removed in Perl 5.9.0

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

# 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.