From: Phrogz <gavin@...>
Date: 2006-10-20T23:10:13+09:00
Subject: Re: Neewby question: how to monitor a variable value

Luc Juggery wrote:
> I remember reading in a book that we could very easily monitor the
> value of a variable and have for instance an alert message displayed
> each time this variable s modified. I do not manage to find how to do
> this anymore.

While I'm sure many other similar libraries exist, I'd like to offer up
my own EventTarget library. Instead of being tied to a single event
like the Observable pattern, you can register different callbacks for
different types of actions that occur.

http://phrogz.net/RubyLibs/rdoc/files/EventTarget_rb.html

One of these days I'll get around to learning how to gem up my libs.
Until then, you can download the source code from the link on that page.