Go编程语言代码错误

Question

我尝试在 GO 中编写一个简单的代码，其中两个 go 例程(发送和接收)相互发送整数。我给出下面的代码。任何人都可以帮助我为什么这个程序的输出是[无输出]。有什么愚蠢的错误吗(抱歉，我是 GO 的新手)？

package main

func Send (in1 <-chan int, out1 chan<- int) {

                i := 2 
        out1 <- i 
    print(i, "\n")
}

func Receive (in <-chan int, out chan<- int) {

        i := <-in 
        print(i, "\n")
        out <- i 
}


func main() {

       for i := 0; i < 10; i++ {
        ch1 := make(chan int)
        ch := make(chan int) 
            go Send (ch1 , ch)
        go Receive (ch , ch1)
        ch = ch1
        ch1 = ch
        }

}

Answer 1

这个怎么样:

package main

func Send (ch chan<- int) {
    for i := 0; i < 10; i++ {
      print(i, " sending\n")
      ch <- i
    }
}

func Receive (ch <-chan int) {
    for i := 0; i < 10; i++ {
        print(<-ch, " received\n")
    }
}

func main() {
   ch := make(chan int)
   go Receive(ch)
   Send(ch)
}

当我在 golang.org 上运行它时，它的输出是:

0 sending
0 received
1 sending
2 sending
1 received
2 received
3 sending
4 sending
3 received
4 received
5 sending
6 sending
5 received
6 received
7 sending
8 sending
7 received
8 received
9 sending

我不确定为什么从未收到 9。应该有一些方法可以让主线程休眠，直到 Receive goroutine 完成。此外，接收方和发送方都知道他们将发送 10 个数字是不雅的。其中一个 goroutine 应该在另一个 goroutine 完成工作时关闭。我不确定该怎么做。

编辑 1:

这是一个有两个 channel 的实现，go 例程在彼此之间来回发送整数。一个被指定为响应者，它只在收到一个 int 后才发送和 int。响应者只需将收到的 int 值加 2，然后将其发回。

package main

func Commander(commands chan int, responses chan int) {
    for i := 0; i < 10; i++ {
      print(i, " command\n")
      commands <- i
      print(<-responses, " response\n");
    }
    close(commands)
}

func Responder(commands chan int, responses chan int) {
    for {
        x, open := <-commands
        if !open {
            return;
        }
        responses <- x + 2
    }
}

func main() {
   commands := make(chan int)
   responses := make(chan int)
   go Commander(commands, responses)
   Responder(commands, responses)
}

当我在 golang.org 上运行它时的输出是:

0 command
2 response
1 command
3 response
2 command
4 response
3 command
5 response
4 command
6 response
5 command
7 response
6 command
8 response
7 command
9 response
8 command
10 response
9 command
11 response