Date.swift

import Cocoa

extension Int {
    var seconds: NSTimeInterval {
    return NSTimeInterval(self)
    }
    
    var minutes: NSTimeInterval {
    return self.seconds * 60
    }
    
    var hours: NSTimeInterval {
    return self.minutes * 60
    }
}

@infix func + (left: NSDate, right: NSTimeInterval) -> NSDate {
    return left.dateByAddingTimeInterval(right)
}

let now = NSDate.init()
let future = now + 6.hours