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Re: Standard behavior for decorations...



On 2009-09-05 18:15:41 +0200, Arnold Neumaier wrote:
> Dan Zuras Intervals schrieb:
> >	(3) A decoration is an event <x> which happened
> >	during the calculation of this result or during the
> >	calculation of some previous result that led up to
> >	this result.  Thus the event is more properly called
> >	<x>Happened.  A decoration may be tested or set but
> >	it may never be cleared.  After all, you cannot make
> >	<x> unhappen at some later date.
> 
> But this can be only locally. There must be a way to throw
> away a decoration when the variable is reused for a new
> function evaluation. Otherwise if an empty decoration was
> present once, all future evaluations would give empty.
> Thus the clearing process must be better specified.

The standard should specify operations/functions in a SSA form,
i.e. a result is always something entirely new, not some object
with a previous state.

-- 
Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.org/>
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Work: CR INRIA - computer arithmetic / Arénaire project (LIP, ENS-Lyon)