TinyGo Goroutine Test on WioTerminal

I try the code TinyGo on Wio Terminal to feel the operation of goroutine 
It is not a preemptive time-share style thread.
So ... beware of long runnung operation.

Following is Simulation of Running Operation
	primeFinder := func(
		done <-chan interface{},
		iStream <-chan int,
	) <-chan interface{} {
		pStream := make(chan interface{})
		go func() {
			defer close(pStream)
			for iV := range iStream {
				iV -= 1
				prime := true
				for d := iV - 1; d > 1; d-- {
					if iV%d == 0 {
						prime = false
						break
					}
				}
				if prime {
					select {
					case <-done:
						return
					case pStream <- iV:
					}
				}
			}
		}()
		return pStream
	}

PS. Use tinygo on wio terminal feel nicer than rust. :(