clientv3/clientv3util/util.go
func KeyMissing(key string) clientv3.Cmp {
	return clientv3.Compare(clientv3.Version(key), "=", 0)
}
func KeyMissing(key string) clientv3.Cmp {
	return clientv3.Compare(clientv3.Version(key), "=", 0)
}
func KeyMissing ( key string ) clientv3 . Cmp { return clientv3 . Compare ( clientv3 . Version ( key ) , " " , 0 ) }
// KeyMissing returns a comparison operation that evaluates to true iff the
// given key does not exist.
KeyMissing returns a comparison operation that evaluates to true iff the given key does not exist .