On Thu, Apr 5, 2018, 5:32 PM Peter O'Connor <peter.ed.oconnor@gmail.com> wrote:
I find this a bit awkward, and maintain that it would be nice to have this as a built-in language construct to do this natively.  You have to admit: 

    smooth_signal = [average = (1-decay)*average + decay*x for x in signal from average=0.]

Is a lot cleaner and more intuitive than:

    dev compute_avg(avg, x):
        return (1 - decay)*avg + decay * x

The proposed syntax strikes me as confusing and mysterious to do something I do only occasionally.  In contrast, itertools.accumulate() is straightforward and far more general.

Definitely -100 on the proposal.