func (r *room) count() int {
	r.RLock()
	defer r.RUnlock()
	return len(r.peers)
}
// count return count of peers in room
count return count of peers in room
// count return count of peers in room
func (r *room) count() int {
	r.RLock()
	defer r.RUnlock()
	return len(r.peers)
}
func ( r * room ) count ( ) int { r . RLock ( ) defer r . RUnlock ( ) return len ( r . peers ) }
count return count of peers in room
count return count of peers in room