PlaygroundFun

Whoa.swift

func +(a: NSAttributedString, b: NSAttributedString) -> NSAttributedString {
    let muty = NSMutableAttributedString(attributedString: a)
    muty.appendAttributedString(b)
    return muty
}

extension String: CustomPlaygroundQuickLookable {
    public func customPlaygroundQuickLook() -> PlaygroundQuickLook {
        let colors: [UIColor] = [
            .redColor(), .orangeColor(), .yellowColor(),
            .greenColor(), .blueColor(), UIColor(red: 75.0/255.0, green: 0.0, blue: 130.0/255.0, alpha: 1.0),
            .purpleColor()
        ]
        let font: UIFont
        let fontSize: CGFloat = 37.0
        if #available(iOS 8.2, *) {
            font = UIFont.systemFontOfSize(fontSize, weight: UIFontWeightUltraLight)
        } else {
            font = UIFont.systemFontOfSize(fontSize)
        }
        let meow = self.characters.enumerate().map({ (i: Int, c: Character) in (colors[i % colors.count], c) })
        return PlaygroundQuickLook.AttributedString(
            meow.reduce(NSAttributedString()) { (accum: NSAttributedString, t: (UIColor, Character)) in
                accum + NSAttributedString(string: String(t.1), attributes: [
                    NSForegroundColorAttributeName  : t.0,
                    NSFontAttributeName             : font
                ])
            }
        )
    }
}

"whoaoaoaoaoaoaoaoaoaoaoaoaoa"

Made with @JohnRHeaton