Generic Instance Method

isSubset(of:)

Returns a Boolean value that indicates whether the set is a subset of the given sequence.

Declaration

func isSubset<S>(of possibleSuperset: S) -> Bool where Element == S.Element, S : Sequence

Parameters

possibleSuperset: A sequence of elements. possibleSuperset must be finite.

Return Value

true if the set is a subset of possibleSuperset; otherwise, false.

Discussion

Set A is a subset of another set B if every member of A is also a member of B.

let employees = ["Alicia", "Bethany", "Chris", "Diana", "Eric"]
let attendees: Set = ["Alicia", "Bethany", "Diana"]
print(attendees.isSubset(of: employees))
// Prints "true"

See Also

Comparing Sets

static func == (Set<Element>, Set<Element>) -> Bool

Returns a Boolean value indicating whether two sets have equal elements.

static func != (Set<Element>, Set<Element>) -> Bool

Returns a Boolean value indicating whether two values are not equal.

func isSubset(of: Set<Element>) -> Bool

Returns a Boolean value that indicates whether this set is a subset of the given set.

func isStrictSubset(of: Set<Element>) -> Bool

Returns a Boolean value that indicates whether the set is a strict subset of the given sequence.

func isStrictSubset<S>(of: S) -> Bool

Returns a Boolean value that indicates whether the set is a strict subset of the given sequence.

func isSuperset(of: Set<Element>) -> Bool

Returns a Boolean value that indicates whether this set is a superset of the given set.

func isSuperset<S>(of: S) -> Bool

Returns a Boolean value that indicates whether the set is a superset of the given sequence.

func isStrictSuperset(of: Set<Element>) -> Bool

Returns a Boolean value that indicates whether the set is a strict superset of the given sequence.

func isStrictSuperset<S>(of: S) -> Bool

Returns a Boolean value that indicates whether the set is a strict superset of the given sequence.

func isDisjoint(with: Set<Element>) -> Bool

Returns a Boolean value that indicates whether this set has no members in common with the given set.

func isDisjoint<S>(with: S) -> Bool

Returns a Boolean value that indicates whether the set has no members in common with the given sequence.