What the Duration of negative Infinity mean?

[Pavel Safrata]

On 31.1.2013 17:11, Martin Sladecek wrote:
> On 01/31/2013 04:56 PM, Richard Bair wrote:
>> I was wondering that as well. My hunch is that being able to have 
>> negative durations would be useful when creating a duration using 
>> math methods on the Duration (add / subtract / etc). I could also 
>> imagine somebody using a Duration where the negative value means to 
>> go backwards vs. forwards or something.
> We currently have negative rates for animations going backwards. 
> Having also negative Durations might just complicate the stuff.

Then to me it would seem consistent to have negative duration going 
backwards as well. Quite naturally, negative duration with negative rate 
would go forward. From the API perspective it doesn't seem complicated. 
Just my 2 cents..

Pavel