A trie data structure where Vmm_core.Name.t elements are the edges, and 'a option is at each nodes.
Since policies are modeled as X.509 arcs, or paths, or domain names - we often need a data structure to access all nodes at the same level (and ensure there's at most one thing at each level.
val empty : 'a tempty is the empty trie.
val insert : Vmm_core.Name.t -> 'a -> 'a t -> 'a t * 'a optioninsert name v t returns the new t', where t'(name) = Some v (this is the only modification). Also, potentially t(name) is returned, if it was present.
val remove : Vmm_core.Name.t -> 'a t -> 'a tremove name t removes the value t(name), and returns the new t'.
val find : Vmm_core.Name.t -> 'a t -> 'a optionfind name t returns the value t(name), if present.
val collect : Vmm_core.Name.t -> 'a t -> (Vmm_core.Name.t * 'a) listcollect name t finds for each sub-element of name the connected values. If name is "foo:bar", ("foo:bar", t("foo:bar")) :: ("foo", t("foo")) :: ("", t("")) :: [] are returned (only the values present are returned.
This is at the moment used in the albatross statistics daemon, but it may be removed soon.
val all : 'a t -> (Vmm_core.Name.t * 'a) listall t flattens the trie into an associative list.
val fold :
Vmm_core.Name.path ->
'a t ->
(Vmm_core.Name.t -> 'a -> 'b -> 'b) ->
'b ->
'bfold path t f init folds f over t at path. Each subnode of path is passed to f.