code: func Instant(marker interface{}, name string, s Scope, args Args) {
  	if c := getContext(marker); c != nil {
  		if args == nil {
  			args = consts.fakeArgs
  		}
  		// getID() is a locking call.
  		c.emit(&event{
  			Type:     eventNestableInstant,
  			Category: "ignored",
  			Name:     name,
  			Scope:    s,
  			Args:     args,
  			ID:       getID(),
  		})
  	}
  }
docs: // Instant registers an intantaneous event that has no duration.