Possible bug on Swift 2?

lazyMapsAndFlatMaps.swift

let array = [1, 2, 3, 4, 5, 6]

array.map { (value) -> [Int] in
    print(value)
    return [value]
}

array.lazy.map { (value) -> [Int] in
    print("value: \(value)")
    return [value]
    }.first

array.lazy.flatMap { (value) -> [Int] in
    print("value: \(value)")
    return [value]
    }.first

array.lazy.flatMap { (value) -> [Int]? in
    print("value: \(value)")
    return value > 3 ? [value] : nil
    }.first