New value type in Foundation

DateInterval.swift

import Foundation

// DateInterval, new value type
let interval1 = DateInterval()
interval1.duration
print("Same start and end date? \(interval1.start == interval1.end)") // True

// Creating a date interval between now and 1 month later
let interval2 = DateInterval(start: Date(), duration: TimeInterval(2_628_000))
interval2.duration
print("Same interval? \(interval1 == interval2)") // False

// Containment
let oneWeekLater = Date(timeIntervalSinceNow: TimeInterval(604_800))
let oneYearLater = Date(timeIntervalSinceNow: TimeInterval(3_1540_000))
interval2.contains(oneWeekLater) // True
interval2.contains(oneYearLater) // False

// Intersection
let interval3 = DateInterval(start: Date(), end: oneWeekLater)
interval2.intersects(interval3) // True
let intersection = interval2.intersection(with: interval3)
if let intersection = intersection {
    print("The intersection starts from \(intersection.start) to \(intersection.end)")
}