On Dec 14, 2007, at 3:06 PM, Rob Biedenharn wrote: > Besides, the code to calculate the, so called, "height" is moot. > There's no "tree" in the data structure upon which a real height can > be said to exist. I see no need to put the Math library to the > test ;-) Yes, I think we should keep testing the concrete features. A height should naturally emerge from that as needed. James Edward Gray II