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stats.mt

import "lib/codec/utf8" =~ [=> UTF8]
import "lib/streams" =~ [=> collectBytes]
import "lib/welford" =~ [=> makeWelford]
exports (main)

def main(_argv, => stdio) as DeepFrozen:
    def bs := collectBytes(stdio<-stdin())
    return when (bs) ->
        def w := makeWelford()
        for line in (bs.split(b`$\n`)):
            if (line =~ b`@_commit @start @stop`):
                def startTime := _makeInt.fromBytes(start)
                def stopTime := _makeInt.fromBytes(stop)
                w((stopTime - startTime).asDouble())
        def stdout := stdio<-stdout()
        def summary := `Mean: ${w.mean()} Std. Dev.: ${w.standardDeviation()} Skew: ${w.skew()} Kurtosis: ${w.kurtosis()}`
        when (stdout<-(UTF8.encode(summary, null)), stdout<-complete()) -> { 0 }