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func gen(nums ...int) <-chan int {
    out := make(chan int)
    go func() {
        for _, n := range nums {
            out <- n
        }
        close(out)
    }()
    return out
}

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func sq(in <-chan int) <-chan int {
    out := make(chan int)
    go func() {
        for n := range in {
            out <- n * n
        }
        close(out)
    }()
    return out
}

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func main() {
    in := gen(2, 3)

    // Distribute the sq work across two goroutines that both read from in.
    c1 := sq(in)
    c2 := sq(in)

    // Consume the merged output from c1 and c2.
    for n := range merge(c1, c2) {
        fmt.Println(n) // 4 then 9, or 9 then 4

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func merge(cs ...<-chan int) <-chan int {
    var wg sync.WaitGroup
    out := make(chan int)

    // Start an output goroutine for each input channel in cs.  output
    // copies values from c to out until c is closed, then calls wg.Done.
    output := func(c <-chan int) {
        for n := range c {
            out <- n
        }

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func hello(done chan bool) {
	fmt.Println("Hello world goroutine")
	done <- true
}
func main() {
	done := make(chan bool)
	go hello(done)
	<-done
	fmt.Println("main function")
}

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// From https://golangbot.com/channels/

func calcSquares(number int, squareop chan int) {  
    sum := 0
    for number != 0 {
        digit := number % 10
        sum += digit * digit
        number /= 10
    }
    squareop <- sum

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timeout := make(chan bool, 1)
go func() {
    time.Sleep(1 * time.Second)
    timeout <- true
}()

select {
case <-ch:
    // a read from ch has occurred
case <-timeout:

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func Query(conns []Conn, query string) Result {
    ch := make(chan Result)
    for _, conn := range conns {
        go func(c Conn) {
            select {
            case ch <- c.DoQuery(query):
            default:
            }
        }(conn)
    }

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package main

import "fmt"

func main() {

	channel := make(chan int)
	done := make(chan bool)
	start := 0
	go playerOne(channel, done)

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apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-nginx
spec:
  selector:
    matchLabels:
      run: my-nginx
  replicas: 2
  template: