1 import UIKit
2
3 var str = "Hello, playground"
4
5 var myVariable = 42
6 myVariable = 50
7 let myConstant = 42
8
9 let implicitInteger = 70
10 let implicitDouble = 70.0
11 let explicitDouble: Double = 70
12 let explicitFloat: Float = 4
13
14 let label = "The width is"
15 let width = 94
16 let widthLabel = label + String(width)
17
18 let apples = 3
19 let oranges = 5
20 let appleSummary = "I have \(apples) apples."
21 let fruitSummary = "I have \(apples + oranges) pieces of fruit."
22
23 let float1 = 1.0
24 let float2 = 3.0
25 let floatString = "\(float1 + float2) CHM, Hi"
26
27 var shoppingList = ["catfish", "water", "tulips", "blue paint"]
28 shoppingList[1] = "bottle of water"
29
30 var occupations = [
31 "Malcolm": "Captain",
32 "Kaylee": "Mechanic",
33 ]
34 occupations["Jayne"] = "public Relations"
35
36 let emptyArray = [String]()
37 let emptyDictionary = [String: Float]()
38 shoppingList = []
39 occupations = [:]
40
41 let individualScores = [75, 43, 103, 87, 12]
42 var teamScore = 0
43 for score in individualScores {
44 if score > 50 {
45 teamScore += 3
46 } else {
47 teamScore += 1
48 }
49 }
50 print(teamScore)
51
52 var optionalString: String? = "Hello"
53 print(optionalString == nil)
54
55 var optionalName: String? = nil
56 var greeting = "Hello!"
57
58 if let name = optionalName {
59 greeting = "Hello, \(name)"
60 } else {
61 greeting = "Hello, CHM"
62 }
63
64 let nickName: String? = nil
65 let fullName: String = "John Appleseed"
66 let informalGreeting = "Hi \(nickName ?? fullName)"
67
68 let vegetable = "red pepper"
69 switch vegetable {
70 case "celery":
71 print("Add some raisins and make ants on a log")
72 case "cucumber", "watercress":
73 print("That would make a good tea sandwich.")
74 case let x where x.hasSuffix("pepper"):
75 print("Is it a spicy \(x)?")
76 default:
77 print("Everything tastes good in soup.")
78 }
79
80 let interestingNumbers = [
81 "Prime": [2, 3, 5, 7, 11, 13],
82 "Fibonacci": [1, 1, 2, 3, 5, 8],
83 "Square": [1, 4, 9, 16, 25],
84 ]
85
86 var largest = 0
87 var largestKind = ""
88 for (kind, numbers) in interestingNumbers {
89 for number in numbers {
90 if number > largest {
91 largest = number
92 largestKind = kind
93 }
94 }
95 }
96
97 print("\(largest, largestKind)")
98
99 var n = 2
100 while n < 100 {
101 n = n * 2
102 }
103 print(n)
104
105 var m = 2
106 repeat {
107 m = m * 2
108 } while m < 100
109 print(m)
110
111 var total = 0
112 for i in 0..<4 {
113 total += i
114 }
115 print(total)
116
117 func greet(person: String, day: String) -> String {
118 return "Hello \(person), today is \(day)."
119 }
120 greet(person: "Bob", day: "Thesday")
121
122 func eat(name: String, food: String) -> String {
123 return "\(name) eat \(food) today."
124 }
125
126 func greet(_ person: String, on day: String) -> String {
127 return "Hello \(person), today is \(day)."
128 }
129 greet("John", on: "Wednesday")
130
131 func calculateStatistics(scores: [Int]) -> (min: Int, max: Int, sum: Int) {
132 var min = scores[0]
133 var max = scores[0]
134 var sum = 0
135
136 for score in scores {
137 if score > max {
138 max = score
139 } else if score < min {
140 min = score
141 }
142 sum += score
143 }
144
145 return(min, max, sum)
146 }
147
148 let statistics = calculateStatistics(scores: [5, 3, 100, 3, 9])
149 print(statistics.sum)
150 print(statistics.2)
151
152 func sumOf(numbers: Int...) -> Int {
153 var sum = 0
154 for number in numbers {
155 sum += number
156 }
157 return sum
158 }
159
160 sumOf()
161 sumOf(numbers: 42, 597, 12)
162
163
164 func returnFifteen() -> Int {
165 var y = 0
166 func add() {
167 y += 5
168 }
169 add()
170 return y
171 }
172 returnFifteen()
173
174 func makeIncrementer() -> ((Int)-> Int) {
175 func addOne(number: Int) -> Int {
176 return 1 + number
177 }
178 return addOne
179 }
180
181 var increment = makeIncrementer()
182 increment(7)
183
184 func hasAnyMatches(list: [Int], condition: (Int) -> Bool) -> Int {
185 for item in list {
186 if condition(item) {
187 return item
188 }
189 }
190 return 0
191 }
192
193 func lessThanTen(number: Int) -> Bool {
194 return number < 10
195 }
196
197 var numbers = [20, 19, 7, 12]
198 hasAnyMatches(list: numbers, condition: lessThanTen)
199
200 numbers.map({
201 (number: Int) -> Int in
202 let result = 3 * number
203 return result
204 })
205
206 let mappedNumbers = numbers.map({number in 3 * number})
207 print(mappedNumbers)
208
209 //let sortedNumbers = numbers.sort{$0 > $1}
210 //print(sortedNumbers)
211
212 class Shape {
213 var numberOfSides = 0
214 let addLetCode = 0
215 func simpleDescription() -> String {
216 return "A shape with \(numberOfSides) sides."
217 }
218
219 func addLetCodeTest(par: Int) -> String {
220 return "a \(par) sides."
221 }
222 }
223
224 var shape = Shape()
225 shape.numberOfSides = 7
226 var shapeDescription = shape.simpleDescription()
227
228 class NamedShape {
229 var numberOfSides: Int = 0
230 var name: String
231
232 init(name: String) {
233 self.name = name
234 }
235
236 func simpleDescription() -> String {
237 return "A shape with \(numberOfSides) sides."
238 }
239 }
240
241 class Square: NamedShape {
242 var sideLength: Double
243
244 init(sideLength: Double, name: String) {
245 self.sideLength = sideLength
246 super.init(name: name)
247 numberOfSides = 4
248 }
249
250 func area() -> Double {
251 return sideLength * sideLength
252 }
253
254 override func simpleDescription() -> String {
255 return "A square with sides of length \(sideLength)."
256 }
257 }
258
259 let test = Square(sideLength: 5.2, name: "my test square")
260 test.area()
261 test.simpleDescription()
262
263 class EquilateralTriangle: NamedShape {
264 var sideLenth: Double = 0.0
265
266 init(sideLength: Double, name: String) {
267 self.sideLenth = sideLength
268 super.init(name: name)
269 numberOfSides = 3
270 }
271
272 var perimeter: Double {
273 get {
274 return 3.0 * sideLenth
275 }
276 set {
277 sideLenth = newValue / 3.0
278 }
279 }
280
281 override func simpleDescription() -> String {
282 return "An equilateral triagle with side of length \(sideLenth)."
283 }
284 }
285
286 var triangle = EquilateralTriangle(sideLength: 3.1, name: "a triangle")
287 print(triangle.perimeter)
288 triangle.perimeter = 9.9
289 print(triangle.sideLenth)
290
291 class TriangleAndSquare {
292 var triangle: EquilateralTriangle {
293 willSet {
294 square.sideLength = newValue.sideLenth
295 }
296 }
297
298 var square:Square {
299 willSet {
300 triangle.sideLenth = newValue.sideLength
301 }
302 }
303
304 init(size: Double, name: String) {
305 square = Square(sideLength: size, name: name)
306 triangle = EquilateralTriangle(sideLength: size, name: name)
307 }
308 }
309
310 var triangleAndSquare = TriangleAndSquare(size: 10, name: "another test shape")
311 print(triangleAndSquare.square.sideLength)
312 print(triangleAndSquare.triangle.sideLenth)
313 triangleAndSquare.square = Square(sideLength:50, name: "larger square")
314 print(triangleAndSquare.triangle.sideLenth)
315
316 enum Rank: Int {
317 case Ace
318 case Two, Three, Four, Five, Six, Seven, Eight, Nine, Ten
319 case Jack, Queen, King
320
321 func simpleDescription() -> String {
322 switch self {
323 case .Ace:
324 return "ace"
325 case .Jack:
326 return "jack"
327 case .Queen:
328 return "queen"
329 case .King:
330 return "king"
331 default:
332 return String(self.rawValue)
333 }
334 }
335
336 }
337
338 let ace = Rank.Ace
339 let aceRawValue = ace.rawValue
340
341 if let convertedRank = Rank(rawValue: 0) {
342 let threeDescription = convertedRank.simpleDescription()
343 }
344
345 enum Suit {
346 case Spades, Hearts, Diamonds, Clubs
347
348 func simpleDescription() -> String {
349 switch self {
350 case .Spades:
351 return "spades"
352 case .Hearts:
353 return "hearts"
354 case .Diamonds:
355 return "diamonds"
356 case .Clubs:
357 return "clubs"
358 }
359 }
360
361 }
362
363 let hearts = Suit.Hearts
364 let heartsDescription = hearts.simpleDescription()
365
366 enum ServerResponse {
367 case Result(String, String)
368 case Failure(String)
369 }
370
371 let success = ServerResponse.Result("6:00 am", "8:09 pm")
372 let failure = ServerResponse.Failure("Out of cheese.")
373
374 switch success {
375 case let .Result(sunrise, sunset):
376 let serverResponse = "Sunrise is at \(sunrise) and sunset is at \(sunset)."
377 case let .Failure(message):
378 print("Failure... \(message)")
379 }
380
381 struct Card {
382 var rank: Rank
383 var suit: Suit
384 func simpleDescription() -> String {
385 return "The \(rank.simpleDescription()) of \(suit.simpleDescription())"
386 }
387 }
388
389 let threeOfSpades = Card(rank: .Three, suit: .Spades)
390 let threeOfSpadesDescription = threeOfSpades.simpleDescription()
391
392 protocol ExampleProtocol {
393 var simpleDescription: String { get }
394 mutating func adjust ()
395 }
396
397 class SimpleClass: ExampleProtocol {
398 var simpleDescription: String = "A very simple class"
399 var anotherProperty: Int = 69105
400 func adjust() {
401 simpleDescription += "Now 100% adjusted."
402 }
403 }
404
405 var a = SimpleClass()
406 a.adjust()
407 let aDescription = a.simpleDescription
408
409 struct SimpleStructure: ExampleProtocol {
410 var simpleDescription: String = "A simple structure"
411 mutating func adjust() {
412 simpleDescription += "(adjusted)"
413 }
414 }
415
416 var b = SimpleStructure()
417 b.adjust()
418 let bDescription = b.simpleDescription
419
420 extension Int: ExampleProtocol {
421 var simpleDescription: String {
422 return "The number \(self)"
423 }
424 mutating func adjust() {
425 self += 42
426 }
427 }
428
429 print(7.simpleDescription)
430 let protocolValue: ExampleProtocol = a
431 print(protocolValue.simpleDescription)
432
433 enum PrinterError: Error {
434 case OutofPaper
435 case NoToner
436 case OnFire
437 }
438
439 func send(job: Int, toPrinter printerName:String) throws -> String {
440 if printerName == "Never Has Toner" {
441 throw PrinterError.OnFire
442 }
443 return "Job sent"
444 }
445
446 do {
447 let printerResponse = try send(job: 1040, toPrinter: "Never Has Toner")
448 print(printerResponse)
449 } catch {
450 print(error)
451 }
452
453 do {
454 let printerResponse = try send(job: 1440, toPrinter: "Never Has Toner")
455 print(printerResponse)
456 } catch PrinterError.OnFire {
457 print("I‘ll just put this over here, with rest of the fire.")
458 } catch let printerError as PrinterError {
459 print("Printer error: \(printerError).")
460 } catch {
461 print(error)
462 }
463
464
465 let printerSuccess = try? send(job: 1884, toPrinter: "Mergenthaler")
466 let printerFailure = try? send(job: 1885, toPrinter: "Never Has Toner")
467
468
469 var fridgeIsOpen = false
470 let fridgeContent = ["milk", "eggs", "leftovers"]
471
472 func fridgecontains (_ food: String) -> Bool {
473 fridgeIsOpen = true
474 defer {
475 fridgeIsOpen = false
476 }
477
478 let result = fridgeContent.contains(food)
479 return result
480 }
481
482 fridgecontains("milk")
483 print(fridgeIsOpen)
484
485 func repeatItem<Item>(repeating item: Item, numberOfTimers: Int) -> [Item] {
486 var result = [Item]()
487 for _ in 0..<numberOfTimers {
488 result.append(item)
489 }
490 return result
491 }
492 repeatItem(repeating: "knock", numberOfTimers: 2)
493
494 enum OptionalValue<Wrapped> {
495 case None
496 case Some(Wrapped)
497 }
498
499 var possibleInteger: OptionalValue<Int> = .None
500 possibleInteger = .Some(100)
501
502 func anyCommonElements<T: Sequence, U: Sequence>(_ lhs: T, _ rhs: U) -> Bool
503 where T.Iterator.Element: Equatable, T.Iterator.Element == U.Iterator.Element {
504 for lhsItem in lhs {
505 for rhsItem in rhs {
506 if lhsItem == rhsItem {
507 return true
508 }
509 }
510 }
511 return false
512 }
513
514 anyCommonElements([1, 2, 3], [3])
时间： 2024-10-05 05:58:25