isStrictSubset(of:)
Returns a Boolean value that indicates whether this set is a strict subset of the given set.
Declaration
func isStrictSubset(of other: Self) -> BoolParameters
- other:
A set of the same type as the current set.
Return Value
true if the set is a strict subset of other; otherwise, false.
Discussion
Set A is a strict subset of another set B if every member of A is also a member of B and B contains at least one element that is not a member of A.
let employees: Set = ["Alicia", "Bethany", "Chris", "Diana", "Eric"]
let attendees: Set = ["Alicia", "Bethany", "Diana"]
print(attendees.isStrictSubset(of: employees))
// Prints "true"
// A set is never a strict subset of itself:
print(attendees.isStrictSubset(of: attendees))
// Prints "false"