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Piece of Content - using Perl's OO features
Object Orientation: Design Techniques example from a Well House Consultants training course
More on Object Orientation: Design Techniques [link]

This example is described in the following article(s):
   • Nuclear Physics comes to our web site - [link]

Source code: poc3 Module: Q907

use strict;
package poc;
sub new {
        my ($class,$title,$otime,$orank,$halflife) = @_;
        my %info = (title => $title, otime => $otime,
                orank => $orank, halflife => $halflife);
        bless \%info,$class; }
sub gettitle {
        my ($ptr_to_hash) = @_;
        return $ptr_to_hash->{title}; }
sub getrank {
        my ($current) = @_;
        my $now = time();
        my $age_in_days = ($now - $current->{otime}) / 3600 / 24;
        my $decaysteps = $age_in_days / $current->{halflife};
        $decaysteps < 0 and $decaysteps = 0; # future content!
        my $decayfactor = 0.5 ** $decaysteps;
        my $rank = sprintf("%.2f",$current->{orank} * $decayfactor);
        return $rank; }
$article1 = new poc("The Vet who hated horses",time(),15,10);
$article2 = new poc("MySQL left join - howto",time()-52*7*24*3600,75,1000);

print "$article1 $article2\n";

print ($article1->gettitle()," - rank is ",$article1->getrank(),"\n");
print ($article2->gettitle()," - rank is ",$article2->getrank(),"\n");
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