Module type `S.SUBSCRIPTION`

Subscriptions of this node to groups

type 'a t
type gid
type group

val empty : 'a t: empty returns the empty subscription set.

val add : group -> 'a -> 'a t -> 'a t: add group 'a t adds group to the subscription set t

val remove : gid -> 'a t -> 'a t: remove group t removes group from the subscription set t

val length : 'a t -> int: length t returns the number of groups in the subscription set.

val is_empty : 'a t -> bool: is_empty t returns true if the subscription set is empty.

val mem : gid -> 'a t -> bool: mem gid t returns true if gid is in the subscription set.

val find : gid -> 'a t -> (group * 'a) option: find gid t returns Some group if gid is in the subscription set, otherwise None.

val filter : (gid -> (group * 'a) -> bool) -> 'a t -> 'a t
val fold : (gid -> (group * 'a) -> 'b -> 'b) -> 'a t -> 'b -> 'b
val iter : (gid -> (group * 'a) -> unit) -> 'a t -> unit
val map : (gid -> (group * 'a) -> group * 'a) -> 'a t -> 'a t
val to_list : 'a t -> (group * 'a) list: to_list t returns the subscription set as list ordered by group ID.