airspeedswift

func myDropFirst<S: SequenceType>(seq: S) -> SequenceOf<S.Generator.Element> {
    return SequenceOf { ()->GeneratorOf<S.Generator.Element> in
        var g = seq.generate()
        let first = g.next()
        // if you prefer your dropFirst to explodinate on empty
        // sequences, add an assert(first != nil) here...
        return GeneratorOf {
            // shouldn't call GeneratorType.next()
            // after it's returned nil the first time
            first == nil ? nil : g.next()

airspeedswift

func f()->(Int,Int) { 
  return (1,1) 
}

func g(f: ()->(Int?,Int?)) -> (Int,Int) {
    let (a,b) = f()
    return (a ?? 0, b ?? 0)
}

// ()->(Int,Int) is substitutable for 

airspeedswift

infix operator |> {
    associativity left
}

func |><T,U>(t: T, f: T->U) -> U {
    return f(t)
}

// this ought to be enough...
func reverse<T: CollectionType>(source: LazyRandomAccessCollection<T>) -> LazyBidirectionalCollection<RandomAccessReverseView<T>> {

airspeedswift

infix operator |> {
    associativity left
}

func |><A,B>(a: A, f: A->B) -> B {
    return f(a)
}

// this ought to be enough...
func reverse<D: CollectionType where D.Index : BidirectionalIndexType>(source: LazyRandomAccessCollection<D>) -> LazyBidirectionalCollection<RandomAccessReverseView<D>> {

airspeedswift

public struct ZipOuter2<S1: SequenceType, S2: SequenceType>: SequenceType {
    private let _s1: S1
    private let _s2: S2
    init(_ s1: S1, _ s2: S2) {
        _s1 = s1
        _s2 = s2
    }
    
    public typealias Generator = GeneratorOf<(S1.Generator.Element?, S2.Generator.Element?)>

airspeedswift

func findFirst<S: SequenceType>(seq: S, predicate: S.Generator.Element -> Bool) -> S.Generator.Element? {
    for x in seq {
        if predicate(x) { return x }
    }
    return nil
}

func not<T>(predicate: T -> Bool) -> (T -> Bool) {
    return { x in !predicate(x) }
}

airspeedswift

// from http://stackoverflow.com/questions/27635981/transform-from-dictionary-to-array-in-swift-without-a-for-loop
//
// Given [
//  "title" : ["abc",  "def"],
//  "time"  : ["1234", "5678", "0123"],
//  "content":["qwerty", "asdfg", "zxcvb"]
// ]
//
// how do you get to this:

airspeedswift

// import Foundation

struct S {
    var i: Int
}

func f(inout s: S) -> Int {
    s.i += 1
    return s.i
}

airspeedswift

func measure(title: String?, call: () -> Void) {
  let startTime = CACurrentMediaTime()
  call()
  let endTime = CACurrentMediaTime()
  if let title = title {
    print("\(title): ")
  }
  println("Time - \(endTime - startTime)")
}

airspeedswift

let count = 12

// Simple class that prints when it is created and destroyed
class Whiner {
    let _i: Int
    init(_ i: Int) { _i = i; println("Init: \(_i)") }
    deinit { println("Deinit: \(_i)") }
}