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lib/set.mli

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+module type RBTreeSet = sig
+    (** Type of members in the set. *)
+    type member
+
+    (** Purely functional set, implemented as a red, black tree. *)
+    type set
+
+    (** The empty set. *)
+    val empty : set
+
+    (** Inserts a new element into the set. Runs in O(log(n)). *)
+    val insert : member -> set -> set
+
+    (** Determines if a specific value is a member of the set. Runs in O(log(n)). *)
+    val member : member -> set -> bool
+
+    (** Computes the union of two sets. Runs in O(mlog(n)), for the first set is of length m and the second is of length n. Hence if the lengths of the sets are known, this algorithm is most efficient if the second set is the longer one. *)
+    val union : set -> set -> set
+
+    (** Creates a set from a list. Will deduplicate if necessary. Runs in O(log(n!)). *)
+    val of_list : member list -> set
+
+    (** Removes the element specified from the set, if it exists. *)
+    val remove : member -> set -> set
+
+    (** Calculates the first set, without any elements that appear in the second. *)
+    val difference : set -> set -> set
+
+    (** Calculates the number of elements in the set. Note this is not tail recursive. Runs in O(n). *)
+    val cardinality : set -> int
+
+end
+
+module type SetSpecification = sig
+    (** Type of members in the set. *)
+    type member
+    (** Comparison should return a value less than 0 for when the first value is smaller, greater than 0 for when the second is smaller, and 0 when they are equivalent. *)
+    val comparison : member -> member -> int
+end
+
+module RBTreeSet (M : SetSpecification) : RBTreeSet with type member = M.member