#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

package Message;
use overload '""' => \&to_s;

sub new {
    my $class   = shift;
    my $msg     = shift;
    my $t       = time();
    my $self    = { message => $msg, t => $t };
    return bless $self, $class;
}

sub to_s {
    my $self = shift;
    return $self->{'message'};
}

1;

package main;
my @msg_queue = ();
push @msg_queue, new Message("Hello");
sleep(1);
push @msg_queue, new Message("World");
print Dumper [grep { time - $_->{'t'} <= 2 } @msg_queue];
sleep(2);
print Dumper [grep { time - $_->{'t'} <= 2 } @msg_queue];