Hexadecimal string from NSDate

NSData+hexadecimal.swift

import Foundation

extension NSData {
    var hexadecimalString: String {
        var result = ""
        enumerateByteRangesUsingBlock { (pointer, range, _) in
            let pointerToBytes = UnsafePointer<UInt8>(pointer)
            let bytes = UnsafeBufferPointer(start: pointerToBytes, count: range.length)
            for v in bytes {
                result.appendContentsOf(String(format:"%02x", v))
            }
        }
        return result
	}
}

let d = NSData(bytes: [0xDE, 0xAD, 0xBE, 0xEF] as [UInt8], length: 4)
let c = d.hexadecimalString // deadbeef