austinzheng

   PROMOTION                         DEMOTION
    (init?)                           (init)
[~~~~~~~~~~~AnyRandomAccessCollection~~~~~~~~~~~]
    ^       ^                       |       |
    |       |                       |       |
    |       |                       v       |
    |    [~~AnyBidirectionalCollection~~]   |
    |       ^                       |       |
    |       |                       |       |
    |       |                       v       v    

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//
//  ExampleCode.swift
//

import UIKit

// MARK: - Protocol

protocol SearchQueryProviderProtocol : class {    // 'class' means only class types can implement it
  func searchQueryData() -> String

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import UIKit

// Running on Xcode 7.0 beta (7A121l)
// All running in a playground
// Open console (View -> Debug Area -> Show Debug Area)

// Define a non-generic free fn taking 1 arg
func notGeneric(x: String) {
  print("notGeneric called")
}

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import UIKit

/// A very simple example view that can accept keyboard input and add or delete text from an enclosed label.
class CustomTextInputView : UIControl, UIKeyInput {

  var label : UILabel?

  override func canBecomeFirstResponder() -> Bool {
    return true
  }

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// Released under the terms of the MIT license.

struct PrefixedPostfixedSequence<T : SequenceType, U where U == T.Generator.Element> : SequenceType {
  private let sequence : T
  private let initial : U?
  private let final : U?

  init(_ sequence: T, initial: U? = nil, final: U? = nil) {
    self.sequence = sequence
    self.initial = initial

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import Foundation

// Build this as an OS X command line project, then run it. It should never terminate.

enum Value<T> {
  case Nil
  case Cons(T, LinkedList<T>)
}

final class LinkedList<T> {

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// Set up mentions plug-in
- (void)viewDidLoad {
    [super viewDidLoad];
    HKWMentionsChooserPositionMode mode = HKWMentionsChooserPositionModeEnclosedTop;
    NSCharacterSet *controlCharacters = [NSCharacterSet characterSetWithCharactersInString:@"@+"];
    HKWMentionsPlugin *mentionsPlugin = [HKWMentionsPlugin mentionsPluginWithChooserMode:mode
                                                                       controlCharacters:controlCharacters
                                                                            searchLength:3];
    self.plugin = mentionsPlugin;
    mentionsPlugin.delegate = [MentionsManager sharedInstance];

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// Text transformer (palindrome)
[self.textView transformSelectedTextWithTransformer:^NSAttributedString *(NSAttributedString *input) {
    NSString *rawInput = [input string];
    NSMutableString *buffer = [NSMutableString string];
    unichar stackC;
    for (NSInteger i=[rawInput length] - 1; i>=0; i--) {
        stackC = [rawInput characterAtIndex:i];
        [buffer appendString:[NSString stringWithCharacters:&stackC length:1]];
    }
    NSDictionary *attrs = [input attributesAtIndex:0 effectiveRange:NULL];

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protocol InitProtocol { init() }

struct SomeStruct<T: InitProtocol> {
    var x: T? = nil
    mutating func instantiate() {
        if x == nil {
            x = T()
        }
    }
}

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

import Cocoa

enum Wildcard : NilLiteralConvertible {
  case Single
  case FromBeginning
  case ToEnd
  case Range(Int)
  case Literal(Int)