ruk·si

🐹 Go
Channel Chaining

Updated at 2013-12-03 23:21

Goroutines and channels as very lightweight and having thousands of goroutines and channels active shouldn't cause any issues.

package main

func assert(condition bool) {
    if !condition {
        panic("assert failed")
    }
}

func increment(left, right chan int) {
    left <- 1 + <-right
}

func main() {
    const N = 100000
    leftmost := make(chan int)
    right := leftmost
    left := leftmost

    // "queue" a lot of increment operations in goroutine threads
    for i := 0; i < N; i++ {
        right = make(chan int)
        go increment(left, right)
        left = right
    }

    // set it going by providing a single value to the one on top of the stack
    // could also simply do `right <- 0`, but that would be a blocking operation
    go func(c chan int) { c <- 0 }(right)

    // the following blocks until the leftmost channel receives a value
    assert(<-leftmost == 100000)
}