GET.swift

@propertyWrapper
struct GET<T: Decodable> {
  private var url: URL
  
  init(url: String) {
    self.url = URL(string: url)!
  }
  
  var wrappedValue: Observer<T> {
    get {
      return { observer in
        AF.request(self.url).validate()
          .responseDecodable(of: T.self) { response in
            observer(response)
        }
      }
    }
  }
  
}