go语言之进阶篇单向channel特点

1、单向channel特点

package main

//"fmt"

func main() {
        //创建一个channel, 双向的
        ch := make(chan int)

        //双向channel能隐式转换为单向channel
        var writeCh chan<- int = ch //只能写，不能读
        var readCh <-chan int = ch  //只能读，不能写

        writeCh <- 666 //写
        //<-writeCh //err,  invalid operation: <-writeCh (receive from send-only type chan<- int)

        <-readCh //读
        //readCh <- 666 //写， err,  invalid operation: readCh <- 666 (send to receive-only type <-chan int)

        //单向无法转换为双向
        //var ch2 chan int = writeCh //cannot use writeCh (type chan<- int) as type chan int in assignment

}