Complex Layout Problem

[Bojsza]

Has anyone ever had to layout an interface that the user can input 
various values into fields and build a logical AND, OR and NOT string?
For example I have two fields sAddr and dAddr in which the user can 
enter any ip address they want. But they also can define a logical 
statement from these fields:

Example: The user enters sAddr 10.10.2.3 dAddr 20.20.1.2 and wants this 
combination OR sAddr 30.20.34.12 AND NOT dAddr 12.10.2.3

This builds the expression

(sAddr 10.10.2.3 AND dAddr 20.20.1.2) OR (sAddr 30.20.34.12 NOT dAddr 
12.10.2.3)

The grouping is key and must be maintained as the user continues to add 
addition statements.

My thought was to have three identical groups of fields...one for each 
logical operator. Allow the user to enter his first requirements, build 
the expression and then see if they have another set of requirements.

Is the most efficient way to approach this? Sorry this is not a 
Revolution specific problem but I was hoping the board would still have 
some insight.

regards,

Glen