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Re: Motion 52: please hold



On 2013-11-21 08:00:40 -0800, Richard Fateman wrote:
> On 11/21/2013 7:48 AM, Vincent Lefevre wrote:
> >Note that x - x is still different from 0 on intervals (see discussion
> >above on what an expression is).
> 
> You don't need intervals for this to be an issue.
> 
> NaN-NaN  is  NaN, not zero.

A language may have Level 1 real expressions (no NaNs at Level 1,
just real numbers), for which x - x can always be simplified to 0.

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