Markrh:PerlProgramming:StrategyPattern

From BluWiki

Code, TRAVEL.pm

package TRAVEL;
use COWBOY;
use HORSE;

# --------------------------------------------- create
sub create {
    my $type = shift;

    if (lc($type) eq 'horse') {
        return new HORSE;
    }
    elsif (lc($type) eq 'cowboy') {
        return new COWBOY;
    }
    else {
        die "Bad type [$type]\n";
    }
}

# --------------------------------------------- doIt
sub doIt() {
    my $self = shift;

    print "TRAVEL. doIt()\n";
    print "foo: ", $self->{foo}, "\n";
}

1;

Code, COWBOY.pm

package COWBOY;

use TRAVEL;
@ISA = qw(TRAVEL);

sub new {
    my $class = shift;
    my $self  = {};
    bless $self, $class;

    $self->{'foo'} = 'bar';

    return $self;
}

sub travel {
    print "mosey\n";
}
1;

Code, HORSE.pm

package HORSE;

use TRAVEL;
@ISA = qw(TRAVEL);

sub new {
    my $class = shift;
    my $self  = {};
    bless $self, $class;

    $self->{'foo'} = 'too';

    return $self;
}

sub travel {
    print "gallop\n";
}

1;

Code, client.pl

#!/perl -w
use strict;

use TRAVEL;

my $o = TRAVEL::create($ARGV[0]);

$o->travel;
$o->doIt;

Output

./client.pl horse
gallop
TRAVEL. doIt()
foo: too

...
...

./client.pl cowboy
mosey
TRAVEL. doIt()
foo: bar

Categories: Perl Programming-Cookbook, Markrh:DesignPatterns