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RE: Motion 42 (not 41): Decoration system, revised text



John, Jurgen,

The idea to decorate intersection with max(dx,dy) and convexHull with
min(dx,dy) doesn't make any sense to me. Where does this idea come from, and
why would someone want to do this?

For example, if these rules are applied to Example 2 in section 8.8.8 for
X=[-1,1], it gives:

	U = f1(intersect([-1,1],[-oo,-2]))
		= f1((Empty,dac)) // (Empty,dac) is contradictory by section
8.8.4
		= (Empty,emp)
	V = (f1([-1,1]),dac)
	W = f1(intersect([-1,1],[2,+oo]))
		= f1((Empty,dac)) // (Empty,dac) is contradictory by section
8.8.4
		= (Empty,emp)

Despite the contradictory intermediate results, taking convexHull of U, V
and W and propagating the min decoration yields a nonempty interval with the
emp decoration:
	(f1([-1,1]),emp)

This doesn't seem at all useful or correct to me. What am I missing?

Nate