fibonacciRx.groovy

@Grab( 'com.netflix.rxjava:rxjava-groovy:0.17.1' )
import rx.Observable
import rx.Observer
import rx.subscriptions.Subscriptions

def fibObs = Observable.create { Observer<BigInteger> observer ->
    Thread t
    t = Thread.start {
        def prev = 0G
        def next = 0G
        while( !t.interrupted() ) {
            def ret = next
            next = prev + ( next ?: 1 )
            prev = ret
            observer.onNext( ret )
        }
    }
    Subscriptions.create { -> t.interrupt() }
}

fibObs.take( 10 ).subscribe { println it }
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