Perl

http://www.perl.org

Installation

• installers for windows, linux and solaris
  • http://www.activestate.com/Products/ActivePerl/

• source for virtually any platform
  • http://www.cpan.org/src/README.html

Tutorials

• http://perldoc.perl.org/perlobj.html
• http://www.unix.org.ua/orelly/perl/advprog/ch07_01.htm
• http://www.evolt.org/article/Camel_POOP_Object_Oriented_Programming_in_Perl/17/50922/
• Google Search

Project Setup

# create a folder "Talker"
# create a file "talker.pm"
# create a file "main.pl"

# from command line
# $ perl main.pl

# interactive shell
# cmd> perl -de0
#  DB<1> use Talker;
#  DB<2> $john = Talker->new;
#  DB<3> $john->sayHello;

# within file "Talker.pm"

package Talker;

sub new {
   my $class = shift;
   bless {} => $class;
}

sub sayHello {
   print "Hello world";
}

1;

# add to Talker.pm
# uses a CPAN module for convenience

use base qw/Class::Accessor/;
__PACKAGE__->mk_accessors(qw/name age/);

sub sayYourName {
  print shift->name;
}

sub sayYourAge {
  print shift->age;
}

sub sayYourClassName {
  print ref shift;
}

sub sayYourInstanceVarName {
  print "LIMITATION: InstanceVarName not available";
}

sub thisMethodName {
  ((caller(1))[3] || "") =~ /.*::(.*)/ ? $1 : "(anonymous)";
}

sub sayHelloAdvanced {
  print shift->thisMethodName, ": Hello world";
}

sub sayYourClassDefinition {
  print "LIMITATION: Reflection not available";
}

# note: does _not_ use reflection, but is file based
# This requires the token __DATA__ be the last thing in Talker.pm
sub sayYourClassCode {
    seek DATA, 0, 0;  #  :-) 
    local $/;
    print <DATA>;
}

# within main.pl

use Talker;

my $john = Talker->new;
$john->sayHello;

$john->name("John Doe Perl");   
$john->age(19);
$john->sayYourName;
$john->sayYourAge;

$john->sayYourClassName 

$john->sayYourInstanceVarName 
$john->sayHelloAdvanced

$john->sayYourClassDefinition
$john->sayYourClassCode