Re: cannot access frame of function

[Jordan Wilson via Digitalmars-d-learn]

On Monday, 18 September 2017 at 21:58:39 UTC, Alex wrote:
On Monday, 18 September 2017 at 18:49:54 UTC, ag0aep6g wrote:

Doesn't work for me. This still fails compilation with the 
same error:

----
import std.algorithm.iteration : sum, cumulativeFold;
void main()
{
    double[5] a;
    auto asum = 1.23;
    auto jProbs = a[].cumulativeFold!((a, b) => (a + b)/asum);
}
----

So, this is a bug, isn't it? I assume, I should file it then...

I have this same issue. Anyone have any thoughts on a workaround?

For example, my attempt at an exponential moving average doesn't 
compile:
auto ema(Range,T) (Range rng, int period, T seed) {
    return rng.cumulativeFold!((a,b) => 
a+(2.0/(period+1))*(b-a))(seed.to!double);
}

So I ended up with this:
auto ema(Range,T) (Range rng, int period, T seed) {
    struct EMA(Range) {
        double currentValue;
        double weighting;
        Range rng;
        this (Range r, int p, double s) {
            currentValue = s;
            weighting = 2.0 / (p+1);
            rng = r;
        }
        auto front() { return currentValue; }
        auto popFront() {
            rng.popFront;
            if (!rng.empty){
                currentValue += (rng.front - 
currentValue)*weighting;
            }
        }
        auto empty() { return rng.empty; }
    }
    return EMA!Range(rng,period,seed.to!double);
}

Thanks,

Jordan