On 9/29/07, Ryan Ingram
first bc = SF sf where sf dt ~(b,d) = ((c,d), sfFirst bc') where (c, bc') = runSF bc dt b
One question I had was about the implementation of "first". Is it important that the pair match be lazy? Or is it safe to make it strict? What are the advantages and disadvantages of each choice?
The pattern match has to be lazy to make ArrowLoop/loop work.
but there's a pretty clear space leak here with repeated "Right" calls, and I'm not sure if the inner signal should see the lost time or not.
In the original implementation, the inner signal function is "suspended" or "frozen in time" when the input stream is not selecting it. While your implementation wants the inner signal function to "remember and recover" the lost time when it's not selected. This would require the inner signal function to handle arbitarily large delta time by itself though. I guess either would make sense in different situations, so the decision is purely yours. Also you should be able to make the leak go away by forcing the accumulated delta time to be fully evaluated before being passed on. Regards, Paul Liu