JSON Example

{ 
  "first": "John",
  "last": "Smith",
  "age": 35,
  "employeed": true,
  "hobbies": [
    "fishing",
    "bowling",
    "programming"
  ],
  "relatives": {
    "mother": "Susan",
    "father": "Eric",
    "siblings": null 
  }
}

Here is a simple mapping JSON types to Swift types(JSON –> Swift)
null ==> nil
Number ==> Int, Float, Double
String ==> Bool
Array ==> [AnyObject]
Object ==> [String:AnyObject]

guard let arrayOfPhotoDictionaries = photosDictionary["photo"] as? [[String:AnyObject]] else {
	print("Cannot find key 'photo' in \(photosDictionary)")
	return
}

for (index, photo) in arrayOfPhotoDictionaries.enumerated(){
	print("\(index):\(photo)")
}

let rarities = ["Free", "Common"]

for rarity in rarities {
	numCostForRarityItemsDictionary[rarity] = 0
	sumCostForRarityDictionary[rarity] = 0
}

guard let rarityForCard = cardDictionary["rarity"] as? String else {
	print("Cannot find key 'rarityForCard' in \(cardDictionary)")
	return
}

numCostForRarityItemsDictionary[rarityForCard]! += 1
sumCostForRarityDictionary[rarityForCard]! += manaCost

guard let arrayOfBasicSetCardDictionaries = parsedHearthstoneJSON["Basic"] as? [[String:AnyObject]] else {
	print("cannot find key 'basic" in \(parsedHearthstoneJSON)")
	return
}