Perl Xmas Carol 2015

Perl's Ghost
Ghost of Perl Past
Ghost of Perl Present
Ghost of Perl Yet to Come
Dec 25, 2015

1. Perl's Ghost

* backwards-compatibilty chains

$ man perlhist

...
THE KEEPERS OF THE PUMPKIN

	Larry	1.000	       1987-Dec-18
	Larry	2.000	       1988-Jun-05
	Larry	3.000	       1989-Oct-18
	Larry	4.000	       1991-Mar-21
	Larry	5.000	       1994-Oct-17
	Sarathy  5.005	       1998-Jul-22
	Sarathy  5.6.0	       2000-Mar-22
	Jarkko	 5.8.0	       2002-Jul-18
	Hugo	 5.9.0	       2003-Oct-27
	Rafael	 5.10.0        2007-Dec-18
	Jesse	 5.11.0        2009-Oct-02
	Jesse	 5.12.0        2010-Apr-12
	Leon	 5.13.0        2010-Apr-20
	Jesse	 5.14.0        2011-May-14
	David G  5.15.0        2011-Jun-20
	Ricardo  5.16.0        2012-May-20
	Zefram	 5.17.0        2012-May-26
	Ricardo  5.18.0        2013-May-18
	Ricardo   5.19.0       2013-May-20
	Ricardo   5.20.0       2014-May-27
	Ricardo   5.21.0       2014-May-27
	Ricardo   5.22.0       2015-Jun-01
	Ricardo   5.23.0       2015-Jun-20

2. Perl Past

"Programming Perl 4th Ed cover" by Source (WP:NFCC#4).
1991, 1996, 2000, 2012

http://perladvent.org/2008/13

3. Perl Present

Comprehensive Perl Archive Network

cpan.org
metacpan.org
CPAN
CPANPLUS
cpanminus (cpanm)
perlbrew

$ brew install cpanm
$ cpanm install Text::SpellChecker

There's More Than One Way to Do It (TMTOWTDI)

#!/usr/bin/env perl
use v5.14;

my %santa;
$santa{claus} = 1;

if ( exists $santa{claus} ) {
    say "ho ho"
}

say 'ho ho' if exists $santa{claus};

say 'ho ho' unless not exists $santa{claus};

say 'ho ho' unless ! exists $santa{claus};

exists $santa{claus} and say "ho ho";

not exists $santa{claus} or say "ho ho";

There's More Than One Way to Do It (TMTOWTDI)

#!/usr/bin/env perl
use v5.14;

# OO
package Santa {
    sub exists {
        1;
    }
}
say 'ho ho' if Santa->exists;

# Functional
sub santa {
    shift->()
}
sub exists {
    1;
}
say 'ho ho' if santa(\&exists);

Perl5 Resources

man pages
man perlintro
man perl
perlmonks.org
YAPC (YAPC::NA, YAPC::EU, YAPC::Asia...)
PGHPW, DCBPW
Philly Perl mongers
phl.pm.org
Web frameworks
mojolicio.us
perldancer.org
PSGI/Plack
Perlweekly
http://perlweekly.com

4. Perl Yet to Come

Perl6

Perl 5 was my rewrite of Perl. I want Perl 6 to be the community's rewrite of Perl and of the community.

--Larry Wall, State of the Onion speech, TPC4 (OSCon 2000)

In development since 2000
1.0 Planned for XMAS 2015
http://perl6.org
http://perl6advent.wordpress.com

Perl6

say "Mlčoch".substr(2,1).uninameLATIN SMALL LETTER C WITH CARON

# Define unicode ÷ to be divided by
sub infix:<÷> (Int $n, Int $m) {
        fail "can't divide by 0" if $m == 0;
        return $n / $m;
}
say 10 ÷ 55

sub present {
    say 'robot'
}
my $paper = &present.wrap(sub { ... } )
presentStub code executed

&present.unwrap($paper)
presentrobot

Perl6

Grammars (slangs)
multi dispatch
gradual typing
addition, subtraction, division

ruby -e 'puts 7/2'
python -c 'print 7/2'
perl -e 'print 7/2'
perl6 -e 'print 7/2'

ruby -e 'puts -7/2'
python -c 'print -7/2'
perl -e 'print -7/2'
perl6 -e 'print -7/2'

ruby -e 'puts .1 + .2 - .3'
python -c 'print .1 + .2 - .3'
perl -e 'print .1 + .2 - .3'
perl6 -e 'print .1 + .2 - .3'

Perl6 for Mere Mortals, Ovid