sets

Functions for Set Manipulation

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 (==).

As returned by new/0.

Functions

new/0

Returns a new empty set.

is_set/1

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

size/1

Returns the number of elements in Set.

to_list/1

Returns the elements of Set as a list.

from_list/1

Returns an set of the elements in List.

is_element/2

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

add_element/2

Returns a new set formed from Set1 with Element inserted.

del_element/2

Returns Set1, but with Element removed.

union/2

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

union/1

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

intersection/2

Returns the intersection of Set1 and Set2.

intersection/1

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

is_disjoint/2

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

subtract/2

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

is_subset/2

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

fold/3

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

filter/2

Filter elements in Set1 with boolean function Pred.