ordsets

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ordsets Functions for Manipulating Sets as Ordered Lists

Sets are collections of elements with no duplicate elements. An ordset is a representation of a set, where an ordered list is used to store the elements of the set. An ordered list is more efficient than an unordered list.

This module provides exactly the same interface as the module sets but with a defined representation. One difference is that while sets considers two elements as different if they do not match (=:=), this module considers two elements as different if and only if they do not compare equal (==).

DATA TYPES


ordered_set()
  as returned by new/0

new() -> Ordset Return an empty set Ordset = ordered_set()

Returns a new empty ordered set.

is_set(Ordset) -> bool() Test for an Ordset Ordset = term()

Returns true if Ordset is an ordered set of elements, otherwise false.

size(Ordset) -> int() Return the number of elements in a set Ordset = term()

Returns the number of elements in Ordset.

to_list(Ordset) -> List Convert an Ordsetinto a list Ordset = ordered_set() List = [term()]

Returns the elements of Ordset as a list.

from_list(List) -> Ordset Convert a list into an Ordset List = [term()] Ordset = ordered_set()

Returns an ordered set of the elements in List.

is_element(Element, Ordset) -> bool() Test for membership of an Ordset Element = term() Ordset = ordered_set()

Returns true if Element is an element of Ordset, otherwise false.

add_element(Element, Ordset1) -> Ordset2 Add an element to an Ordset Element = term() Ordset1 = Ordset2 = ordered_set()

Returns a new ordered set formed from Ordset1 with Element inserted.

del_element(Element, Ordset1) -> Ordset2 Remove an element from an Ordset Element = term() Ordset1 = Ordset2 = ordered_set()

Returns Ordset1, but with Element removed.

union(Ordset1, Ordset2) -> Ordset3 Return the union of two Ordsets Ordset1 = Ordset2 = Ordset3 = ordered_set()

Returns the merged (union) set of Ordset1 and Ordset2.

union(OrdsetList) -> Ordset Return the union of a list of Ordsets OrdsetList = [ordered_set()] Ordset = ordered_set()

Returns the merged (union) set of the list of sets.

intersection(Ordset1, Ordset2) -> Ordset3 Return the intersection of two Ordsets Ordset1 = Ordset2 = Ordset3 = ordered_set()

Returns the intersection of Ordset1 and Ordset2.

intersection(OrdsetList) -> Ordset Return the intersection of a list of Ordsets OrdsetList = [ordered_set()] Ordset = ordered_set()

Returns the intersection of the non-empty list of sets.

is_disjoint(Ordset1, Ordset2) -> bool() Check whether two Ordsets are disjoint Ordset1 = Ordset2 = ordered_set()

Returns true if Ordset1 and Ordset2 are disjoint (have no elements in common), and false otherwise.

subtract(Ordset1, Ordset2) -> Ordset3 Return the difference of two Ordsets Ordset1 = Ordset2 = Ordset3 = ordered_set()

Returns only the elements of Ordset1 which are not also elements of Ordset2.

is_subset(Ordset1, Ordset2) -> bool() Test for subset Ordset1 = Ordset2 = ordered_set()

Returns true when every element of Ordset1 is also a member of Ordset2, otherwise false.

fold(Function, Acc0, Ordset) -> Acc1 Fold over set elements Function = fun (E, AccIn) -> AccOut Acc0 = Acc1 = AccIn = AccOut = term() Ordset = ordered_set()

Fold Function over every element in Ordset returning the final value of the accumulator.

filter(Pred, Ordset1) -> Set2 Filter set elements Pred = fun (E) -> bool() Set1 = Set2 = ordered_set()

Filter elements in Set1 with boolean function Fun.