[question] why use count field in loop not len(fdconns)?

[Ccheers]

type loop struct {
	idx     int            // loop index in the server loops list
	poll    *internal.Poll // epoll or kqueue
	packet  []byte         // read packet buffer
	fdconns map[int]*conn  // loop connections fd -> conn
	count   int32          // connection count
}

why not use len(fdconns) instead of count?