使用 select with timeouts

所以在这里，我已经删除了 for 循环，并通过向 select 添加第二个 case 并在 3 秒后返回来超时。因为 select 等到任何情况都是真的，第二个 case 会发射，然后我们的脚本结束，而 chatter() 甚至都没有机会完成。

// Use of the select statement with channels, for timeouts, etc.
package main

import (
    "fmt"
    "time"
)

// Function that is "chatty"
//Takes a single parameter a channel to send messages down
func chatter(chatChannel chan<- string) {
    // loop ten times and die
    time.Sleep(5 * time.Second) // sleep for 5 seconds
    chatChannel<- fmt.Sprintf("This is pass number %d of chatter", 1)
}

// out main function
func main() {
    // Create the channel, it will be taking only strings, no need for a buffer on this project
    chatChannel := make(chan string)
    // Clean up our channel when we are done
    defer close(chatChannel)

    // start a go routine with chatter (separate, no blocking)
    go chatter(chatChannel)

    // select statement will block this thread until one of the two conditions below is met
    // because we have a default, we will hit default any time the chatter isn't chatting
    select {
    // anytime the chatter chats, we'll catch it and output it
    case spam := <-chatChannel:
        fmt.Println(spam)
    // if the chatter takes more than 3 seconds to chat, stop waiting
    case <-time.After(3 * time.Second):
        fmt.Println("Ain't no time for that!")
    }
}