Go 中的管道模式

func produce(num int) chan int {
    out := make(chan int)
    go func() {
        for i := 0; i < num; i++ {
            out <- rand.intn(100)
        }
        close(out)
    }()
    return out
}

func double(input <-chan int) chan int {
    out := make(chan int)
    go func() {
        for value := range input {
            out <- value * 2
        }
        close(out)
    }()
    return out
}

func filterbelow10(input <-chan int) chan int {
    out := make(chan int)
    go func() {
        for value := range input {
            if value > 10 {
                out <- value
            }
        }
        close(out)
    }()
    return out
}

func print(input <-chan int) {
    for value := range input {
        fmt.printf("value is %d\n", value)
    }
}

func main() {

    print(filterbelow10(double(produce(10))))

}

func main() {

    input := produce(10)
        doubled := double(input)
    filtered := filterBelow10(doubled)
    print(filtered)

}