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Re: Comments on Motion 27-A "Decorated Intervals"

Vincent Lefever wrote:

sqrt(([1,4],saf) Union (Empty,ndf)) = ([1,2],ndf)

but the motion is not clear about Union. If ndf is not propagated,
then the corresponding exception is lost,


I agree the exception would be lost:
Third paragraph of 1.3.3 in Motion 27 says the minimum decoration of the two operands is chosen (as in your example above). 

Nate



while "decorations are
properties that carry information on the history of the interval"
(and the motion would need to specify the decoration of the union
of several empty sets).

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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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