gistfile1.PL

#!/usr/bin/perl -w

package Foo;

use strict;

sub new {
    my $class = shift;
    my $foo = shift;

    my $self = { foo => $foo };

    return bless $self, $class;
}

sub bar {
    my $self = shift;
    
    print "foo = " . $self->{foo} . "\n";
}

1;

package main;

use strict;

my $foo = Foo->new('blah');
$foo->bar();