2009/12/15 Glurk
So, I'm just thinking that in the real world, we typically do think of changing objects, so a model which also has this property, can help in understanding.
Ah but Glurk, a model that has this property can often greatly _hinder_ understanding: Its well know in OO circles that state change is problematic for 'modelling' - vis the damage done to a circle or square object by the otherwise standard operation of a non-uniform scale, where the circle is obliged to become an ellipse, the square an oblong. [1] Typestate object oriented languages exist where one can migrate e.g a closed file object into an open file and back again, but are somewhat off the beaten path, seemingly doomed to be curios every once in a while at POPL, OOPSLA... Best wishes Stephen [1] http://en.wikipedia.org/wiki/Circle-ellipse_problem [2] http://www.cs.cmu.edu/~aldrich/papers/onward2009-state.pdf