Similar to time.Ticker but fires immediately.

ticker.go

import (
	"log"
	"time"
)

func main() {
	const d = 3 * time.Second
	
	t := time.NewTimer(0)
	defer t.Stop()
	
	for {
		// You can also use `select` here for `context.Context`
		<-t.C
		t.Reset(d)
		
		log.Println("fire!")
	}
}