Date+Strideable and laziness of stride test

Date+Strideable.swift

import Foundation

extension Date: Strideable {
    public typealias Stride = TimeInterval

    public func distance(to other: Date) -> Stride {
        return other.timeIntervalSince(self)
    }

    public func advanced(by n: Stride) -> Date {
        return self.addingTimeInterval(n)
    }
}

test.swift

let d0 = Date(timeIntervalSince1970: 0)
let d10 = Date(timeIntervalSince1970: 10)

print(d0.timeIntervalSince(d10))
print(0.distance(to: 10))

let t1 = stride(from: d0, through: d10, by: 2)
let t2 = t1.lazy
let t3: LazyMapSequence<StrideThrough<Date>, Date> = t2.map { elem -> Date in
	print("mapTo: \(elem)")
	return elem.addingTimeInterval(1)
}

for i in t3.prefix(2) {
	print("access: \(i)")
}