golang学习笔记——select

package main
import (
    "fmt"
    "time"
)
func main() {
    ch := make(chan int)
    o := make(chan bool)
    go func() {
         for {
                 select {
                 case <-time.After(3 * time.Second):
                         fmt.Println("超时")
                         o <- true
                 case num := <-ch:
                         fmt.Println(num)
                 }
         }
    }()
    <-o
}