40 lines
1.1 KiB
Go
40 lines
1.1 KiB
Go
// We often want to execute Go code at some point in the
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// future, or repeatedly at some interval. Go's built-in
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// _timer_ and _ticker_ features make both of these tasks
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// easy. We'll look first at timers and then
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// at [tickers](tickers).
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package main
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import "time"
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import "fmt"
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func main() {
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// Timers represent a single event in the future. You
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// tell the timer how long you want to wait, and it
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// provides a channel that will be notified at that
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// time. This timer will wait 2 seconds.
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timer1 := time.NewTimer(2 * time.Second)
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// The `<-timer1.C` blocks on the timer's channel `C`
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// until it sends a value indicating that the timer
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// expired.
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<-timer1.C
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fmt.Println("Timer 1 expired")
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// If you just wanted to wait, you could have used
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// `time.Sleep`. One reason a timer may be useful is
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// that you can cancel the timer before it expires.
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// Here's an example of that.
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timer2 := time.NewTimer(time.Second)
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go func() {
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<-timer2.C
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fmt.Println("Timer 2 expired")
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}()
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stop2 := timer2.Stop()
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if stop2 {
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fmt.Println("Timer 2 stopped")
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}
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}
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