Those are just functions that return -1,0 or 1. Thats easy enough. I'm talking about control statements that can respond to suck input. if,unless,while...etc all respond to only a true and false and have two actions accordingling (continue looping, execute statment, etc). What I'm wondering is what does a trinary language look like in control statments, and what use is it realy? Of course I never saw the use of LISP so perhaps I'm too short sighted :-)