add timer

timer.go

@@ -0,0 +1,27 @@
+package main
+
+import "time"
+
+type timer struct {
+	number int64
+	unit   string
+}
+
+func (t *timer) Duration() time.Duration {
+	switch t.unit {
+	case "min":
+		return time.Duration(t.number) * time.Minute
+	case "nsec":
+		return time.Duration(t.number) * time.Nanosecond
+	case "usec": // micro seconds
+		return time.Duration(t.number) * time.Nanosecond * time.Duration(1000)
+	case "msec":
+		return time.Duration(t.number) * time.Nanosecond * time.Duration(1000000)
+	case "hour":
+		return time.Duration(t.number) * time.Hour
+	case "sec":
+		return time.Duration(t.number) * time.Second
+	default:
+		return time.Second
+	}
+}