>> On a more positive note, according to our current plans, VW 7.7 will
>> provide vastly improved IEEE arithmetic including proper support for INF
>> and NaN.
>>
>> Andres.
>>
>>     
>
> That's good news.
> Concerning NaN and Inf, I wonder if really a great idea. This
> introduces all sort of complexifications in the image.
>
>   

I don't know... I wouldn't call 7.7's state complex, given what you're 
getting.  But... I guess you'll have to be the judge of that when it 
comes out :).

> The main point of exceptional values is to avoid interrupting FP
> computations and rather introduce sparse tests at strategic points in
> code. It must be viewed as an optimization.
> Knowing that Smalltalk has all sort of overhead on FP computations, I
> wonder if adding a isFinite test in primitives at each operation and
> raising an Exception immediately rather than differed at chosen points
> was not a better compromise....
>   

In VW, you can choose between FP primitives that fail before answering 
INF or NaN, or primitives that will give you whatever the FPU says.  
This decision can be made at runtime.  The default is the legacy 
behavior of prims that fail before answering INF or NaN.

Andres.

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