// future, or repeatedly at some interval. Go's built-in

// _timer_ and _ticker_ features make both of these tasks

// easy. We'll look first at timers and then

// at [tickers](tickers).

​

package main

​

import "time"

import "fmt"

​

func main() {

​

    // Timers represent a single event in the future. You

    // tell the timer how long you want to wait, and it

    // provides a channel that will be notified at that

    // time. This timer will wait 2 seconds.

    timer1 := time.NewTimer(time.Second * 2)

​

    // The `<-timer1.C` blocks on the timer's channel `C`

    // until it sends a value indicating that the timer

    // expired.

    <-timer1.C

    fmt.Println("Timer 1 expired")

​

    // If you just wanted to wait, you could have used

    // `time.Sleep`. One reason a timer may be useful is

    // that you can cancel the timer before it expires.

    // Here's an example of that.

    timer2 := time.NewTimer(time.Second)

    go func() {

        <-timer2.C

        fmt.Println("Timer 2 expired")

    }()

    stop2 := timer2.Stop()

    if stop2 {

        fmt.Println("Timer 2 stopped")

    }

}

​