From: Tim Fletcher <twoggle@...>
Date: 2006-10-21T06:10:19+09:00
Subject: [ANN] Dependency 1.0.0

A Smalltalk-inspired dependency mechanism for Ruby. Like this:

    class StockWatcher
      include Dependency::Methods
      def initialize(stock)
        stock.express_interest_in :price, :for => self, :send_back =>
:price_changed
      end
      def price_changed(old_price, stock)
        # gets called whenever the stock object changes it's price
      end
    end

Completely unrelated to Rails' dependency code - similar to observers
though.

http://rubyforge.org/projects/dependency

gem install dependency