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Anthony Lafont
17,075 PointsI get a compiler error "type VendingMachine does not conform to protocol vendingMachineType"
I get a compiler error "type VendingMachine does not conform to protocol vendingMachineType" for the "VendingMachine" class. I can't understand why. Does somebody know?
Here is my code (sorry for the layout):
import Foundation
// Protocols
protocol VendingMachineType { var selection: [vendingSelection] { get } var inventory: [vendingSelection: ItemType] { get set } var amountDeposited: [Double] { get set }
init(inventory : [vendingSelection: ItemType])
func vend (selection: vendingSelection, quantity: Double) throws
func deposit (amount: Double)
}
protocol ItemType { var price: Double { get } var quantity : Double { get set } }
// Error Types
enum inventoryError: ErrorType{ case InvalidResource case ConversionError case InvalidKey }
// Helper Class
class PlistConveter { class func dictionaryFromFile(resource: String, ofType type: String) throws -> [String : AnyObject] { guard let path = NSBundle.mainBundle().pathForResource(resource, ofType: type) else { throw inventoryError.InvalidResource } guard let dictionary = NSDictionary(contentsOfFile: path), let castDictionary = dictionary as? [String : AnyObject] else { throw inventoryError.ConversionError } return castDictionary } }
class inventoryUnarchiver { class func vendingInventoryFromDictionary(dictionary: [String : AnyObject]) throws -> [vendingSelection : ItemType] { var inventory: [vendingSelection: ItemType] = [:]
for (key,value) in dictionary {
if let itemDict = value as? [String : Double], let price = itemDict["price"], let quantity = itemDict["quantity"] {
let item = VendingItem(price: price, quantity: quantity)
guard let key = vendingSelection(rawValue: key) else {
throw inventoryError.InvalidKey
}
inventory.updateValue(item, forKey: key)
}
}
return inventory
}
}
// Concrete Types
enum vendingSelection: String { case Soda case DietSoda case Chips case Cookie case Sandwich case Wrap case CandyBar case PopTart case Water case FruitJuice case SportsDrink case Gum }
struct VendingItem : ItemType { var price: Double var quantity: Double }
class VendingMachine: VendingMachineType { let selection: [vendingSelection] = [.Soda, .DietSoda, .Chips, .Cookie, .Sandwich, .Wrap, .CandyBar, .PopTart, .Water, .FruitJuice, .SportsDrink, .Gum] var inventory: [vendingSelection : ItemType] var amountDeposited: Double = 10.0
required init(inventory: [vendingSelection : ItemType]) {
self.inventory = inventory
}
func vend(selection: vendingSelection, quantity: Double) throws {
// Add code
}
func deposit(amount: Double) {
// Add code
}
}
4 Answers

Darya Slobodyanik
14,125 PointsThe amountDeposited variable in your VendingMachineType protocol should be a Double instead of a [Double]. :)

Parth Patel
5,951 PointsYou should have
" // Concrete Types enum VendingSelection: String { case Soda case DietSoda case Chips case Cookie case Sandwich case Wrap case CandyBar case PopTart case Water case FruitJuice case SportsDrink case Gum } "
and make sure the v in VendingSelection is capitalized if its capitalized where you defined it.

Anthony Lafont
17,075 PointsThanks for the answer, but it seems it's not the only problem I had with my code. I still have my compiler error! I repost my code with good format
import Foundation
// Protocols
protocol VendingMachineType {
var selection: [VendingSelection] { get }
var inventory: [VendingSelection: ItemType] { get set }
var amountDeposited: [Double] { get set }
init(inventory : [VendingSelection: ItemType])
func vend (selection: VendingSelection, quantity: Double) throws
func deposit (amount: Double)
}
protocol ItemType {
var price: Double { get }
var quantity : Double { get set }
}
// Error Types
enum InventoryError: ErrorType {
case InvalidResource
case ConversionError
case InvalidKey
}
// Helper Class
class PlistConveter {
class func dictionaryFromFile(resource: String, ofType type: String) throws -> [String : AnyObject] {
guard let path = NSBundle.mainBundle().pathForResource(resource, ofType: type) else {
throw InventoryError.InvalidResource }
guard let dictionary = NSDictionary(contentsOfFile: path), let castDictionary = dictionary as? [String : AnyObject] else {
throw InventoryError.ConversionError }
return castDictionary
}
}
class inventoryUnarchiver {
class func vendingInventoryFromDictionary(dictionary: [String : AnyObject]) throws -> [VendingSelection : ItemType] {
var inventory: [VendingSelection: ItemType] = [:]
for (key,value) in dictionary {
if let itemDict = value as? [String : Double], let price = itemDict["price"], let quantity = itemDict["quantity"] {
let item = VendingItem(price: price, quantity: quantity)
guard let key = VendingSelection(rawValue: key) else {
throw InventoryError.InvalidKey
}
inventory.updateValue(item, forKey: key)
}
}
return inventory
}
}
// Concrete Types
enum VendingSelection: String {
case Soda
case DietSoda
case Chips
case Cookie
case Sandwich
case Wrap
case CandyBar
case PopTart
case Water
case FruitJuice
case SportsDrink
case Gum
}
struct VendingItem : ItemType {
var price: Double
var quantity: Double
}
class VendingMachine: VendingMachineType {
let selection: [VendingSelection] = [.Soda, .DietSoda, .Chips, .Cookie, .Sandwich, .Wrap, .CandyBar, .PopTart, .Water, .FruitJuice, .SportsDrink, .Gum]
var inventory: [VendingSelection : ItemType]
var amountDeposited: Double = 10.0
required init(inventory: [VendingSelection : ItemType]) {
self.inventory = inventory
}
func vend(selection: VendingSelection, quantity: Double) throws {
// Add code
}
func deposit(amount: Double) {
// Add code
}
}

Anthony Lafont
17,075 PointsThanks a lot Darya! I've been looking for this error for weeks!