StringLiteralConvertibleExample.swift

struct Car: StringLiteralConvertible {
  
  enum CarType: String {
    case Mercedes, Porsche, Ford, Unknown
  }
  
  var type: CarType
  
  typealias ExtendedGraphemeClusterLiteralType = StringLiteralType
  
  init(unicodeScalarLiteral value: String) {
    self.init(carTypeString: value)
  }
  
  init(extendedGraphemeClusterLiteral value: String) {
    self.init(carTypeString: value)
  }
  
  init(stringLiteral value: String) {
    self.init(carTypeString: value)
  }
  
  init(carTypeString: String) {
    let type = CarType(rawValue: carTypeString) ?? .Unknown
    self.init(carType: type)
  }
  
  init(carType: CarType) {
    self.type = carType
  }

  
}

let car: Car = "Mercedes"
print(car.dynamicType)