tLewisII

import Foundation

precedencegroup LeftApplyPrecedence {
    associativity: left
    higherThan: AssignmentPrecedence
    lowerThan: TernaryPrecedence
}

precedencegroup FunctionCompositionPrecedence {
    associativity: right

tLewisII

protocol CellWithIdentifier:class {
    associatedtype T = Self
    static var resuseIdentifier: String { get }
}

extension UICollectionViewCell:CellWithIdentifier { }
extension UITableViewCell:CellWithIdentifier { }

extension CellWithIdentifier {
    static var resuseIdentifier: String { return String(self) }

tLewisII

extension String {
    var isHomogeneous:Bool {
        let charSet = Set(self.characters)
        return charSet.count == 0 || charSet.count == 1
    }
}

tLewisII

// Need both of these, since one `adaptivePresentationStyleForPresentationController:` works on 8.0 to 8.2, and the other,
// `adaptivePresentationStyleForPresentationController:traitCollection:` works on 8.3 plus
- (UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller {
    return UIModalPresentationNone;
}

- (UIModalPresentationStyle)adaptivePresentationStyleForPresentationController:(UIPresentationController *)controller traitCollection:(UITraitCollection *)traitCollection {
    return UIModalPresentationNone;
}

tLewisII

// this...

override func prepareForSegue(segue: UIStoryboardSegue!, sender: AnyObject!) {
        let group = data?[self.tableView.indexPathForSelectedRow().row]
        if let destination = segue.destinationViewController as? ViewController {
            destination.title = group?.valueForProperty(ALAssetsGroupPropertyName) as? NSString
            destination.data = PhotoManager.lazySendableForGroup(manager) <^> group
        } else {
            println("Cast failed, proposed class of segue view controller is wrong")
        }

tLewisII

// Playground - noun: a place where people can play

import Cocoa

enum StringAttribute {
    case List([StringAttribute])
    case Font(NSFont)
    case BgColor(NSColor)
    case FgColor(NSColor)
    

tLewisII

let userjs: NSData = "{\"name\": \"max\", \"age\": 10, \"tweets\": [\"hello\"], \"attrs\": {\"one\": \"1\", \"more\": {\"stuff\": \"again\"}}}"
    .dataUsingEncoding(NSUTF8StringEncoding, allowLossyConversion: false)
let val =  JSValue.decode(userjs)

let traversal = JSValue.key("attrs") • JSValue.key("more") • JSValue.key("stuff")

let getIt = traversal.get(val)
let setIt = traversal.set(val, JSValue.JSString("bob"))

tLewisII

//this is a playground
struct Reader<R,A> {
    let f:R -> A
    
    init(_ fun:R -> A) {
        f = fun
    }
    
    static func wrap(val:A) -> Reader<R,A> {
        return Reader({_ in val})

tLewisII

operator infix <> {
associativity left
}

protocol Monoid {
    typealias M
    func mempty() -> M
    func mappend(a:M) -> M
}

tLewisII

//bind
operator infix >>= {
associativity left
}

struct Writer<A> {
    let a:A
    let s:String[]
    
    init(_ a:A, _ s:String[]) {