I am attemptiong to write a package which consists of a workspace
divided into nodes.  Each node has several voltages associated with it.
Generally one manipulates these voltages to change the state of the 
node, and to pass signals between nodes.  However, these voltages
group into ports when communicating between nodes.  A port can have
more properties than a voltage, but different properties from a node.
For example, some ports allow voltages to be passed across them, others
reflect them back the way they came.  A port usually consists of two
voltages.  A node usually has six ports (i.e 12 voltages).

I asked someone about how to do this neatly on an OO way, and they 
said, "have the ports contain references to the voltages".  However,
I cannot see any reference or pointer types in ruby.  Is there a
neat way of doing this in ruby?

	Hugh
	hgs / dmu.ac.uk