Es-discuss - several decimal discussions

Brendan Eich brendan at mozilla.org
Sun Aug 24 23:20:35 PDT 2008


On Aug 24, 2008, at 10:02 PM, Mark S. Miller wrote:

> Let's say you did that -- make a special case for NaN but not for -0.
> Let's say you use this Map to build memoize. Now let's say someone
> writes a purely functional function F such that F(0) is 3 and F(-0) is
> 7. Let's say G is memoize(F). Would you find it acceptable for G(0) to
> sometimes yield 3 and sometimes 7?

I'd file a bug, or find a better memoizer :-). "Quality of  
implementation" eager beavers can use Math.atan2 to tell -0 from 0,  
just as they can use isNaN or x !== x.

Yes, this is gross. I'm in favor of Object.identical and  
Object.hashcode, maybe even in ES3.1 (I should get my act together  
and help spec 'em). Just not particularly on account of Decimal, even  
with equated cohort members. I still agree with Sam. And as  
always,"hard cases make bad law".

/be


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