If you can accept that the method is added to the class (and not just to this one instance in the way you can have singleton-methods e.g. in Ruby) this is very simple as methods are just symbol-table entries just like any other sub.

Here an example that adds a new "bubba" method to a "Hubba"-class after an instance already has been created: 

use strict;

package Hubba;

sub new {
 my($pck)=@_;

 bless {}, $pck;
}

# no bubba-method defined here

package main;

# create new instance
my $h = new Hubba;

# add entry to symbol-table
*Hubba::bubba = sub { print "bubba" };

# call new method via old instance
$h->bubba;

In reply to Re: Can I add methods to an existing object? by morgon
in thread Can I add methods to an existing object? by pileofrogs

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