英文:
Why same Go Channel can't be started twice?
问题
在Go语言中，不能重复使用已声明的通道。如果尝试两次使用同一个通道，会得到该通道的默认值。因此，如果要再次使用通道，需要声明另一个通道。这是Go语言的设计选择，旨在确保通道的正确使用和避免潜在的错误。
英文:
Can we start the one decalred channel twice in Go lang ?
package main
import (
"fmt"
)
func emit(c chan string) {
words := []string {"The", "quick", "brown", "fox"}
for _, word := range words {
c <- word
}
close(c)
}
In the function main If i try to use the same channel twice i'm getting default value of that channel
func main() {
wordChannel := make(chan string)
go emit(wordChannel)
for word := range wordChannel {
fmt.Printf("%s ", word)
}
go emit(wordChannel)
word1 := <-wordChannel
fmt.Printf("%s" , word1) // prints Default value
}
So to use it again i've to declare another channel.
If this is not an error why this was done in the Go Lang. ?
i'm using go -lang version 1.6
答案1
得分: 6
通道并不是“启动”的，通道只是存在，并处于以下两种状态之一：
- “打开”状态，此时您可以向其发送值（并接收发送的值）。
- “关闭”状态，此时您无法发送值，并且从关闭的通道接收值会返回“零值，false”。
一旦通道关闭，它将永远保持关闭状态。因此，在Go语言中，您必须创建一个新的通道，而没有“重新打开”的操作。
英文:
Channels are not "started", channels simply exist and are in one of two states:
- "open" in which case you can send values to them (and receive the values sent), or
- "closed" in which you cannot send and receiving from a closed channel results in "the-zero-value, false".
A once closed channel stays closed forever. So yes, you have to make a new channel, there is no "reopen" in Go.
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论