DESCRIPTION

Sets are collections of elements with no duplicate elements. The representation of a set is not defined.

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

DATA TYPES

set(Element)

As returned by new/0.

set()

set() is equivalent to set(term()).

EXPORTS


new() -> set()

Returns a new empty set.


is_set(Set) -> boolean()

Types:

Set = term()

Returns true if Set is a set of elements, otherwise false.


size(Set) -> integer() >= 0

Types:

Set = set()

Returns the number of elements in Set.


to_list(Set) -> List

Types:

Set = set(Element)

List = [Element]

Returns the elements of Set as a list.


from_list(List) -> Set

Types:

List = [Element]

Set = set(Element)

Returns an set of the elements in List.


is_element(Element, Set) -> boolean()

Types:

Set = set(Element)

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


add_element(Element, Set1) -> Set2

Types:

Set1 = Set2 = set(Element)

Returns a new set formed from Set1 with Element inserted.


del_element(Element, Set1) -> Set2

Types:

Set1 = Set2 = set(Element)

Returns Set1, but with Element removed.


union(Set1, Set2) -> Set3

Types:

Set1 = Set2 = Set3 = set(Element)

Returns the merged (union) set of Set1 and Set2.


union(SetList) -> Set

Types:

SetList = [set(Element)]

Set = set(Element)

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


intersection(Set1, Set2) -> Set3

Types:

Set1 = Set2 = Set3 = set(Element)

Returns the intersection of Set1 and Set2.


intersection(SetList) -> Set

Types:

SetList = [set(Element), ...]

Set = set(Element)

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


is_disjoint(Set1, Set2) -> boolean()

Types:

Set1 = Set2 = set(Element)

Returns true if Set1 and Set2 are disjoint (have no elements in common), and false otherwise.


subtract(Set1, Set2) -> Set3

Types:

Set1 = Set2 = Set3 = set(Element)

Returns only the elements of Set1 which are not also elements of Set2.


is_subset(Set1, Set2) -> boolean()

Types:

Set1 = Set2 = set(Element)

Returns true when every element of Set11 is also a member of Set2, otherwise false.


fold(Function, Acc0, Set) -> Acc1

Types:

Function = fun((Element, AccIn) -> AccOut)

Set = set(Element)

Acc0 = Acc1 = AccIn = AccOut = Acc

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


filter(Pred, Set1) -> Set2

Types:

Pred = fun((Element) -> boolean())

Set1 = Set2 = set(Element)

Filter elements in Set1 with boolean function Pred.

RELATED TO sets…

ordsets(3erl), gb_sets(3erl)