Vfrdtyky

After downcasting an array of structs, my Variables View window shows that all of the values in my struct have shifted "down" (will explain in a second). But when I print(structName), the values are fine. However, when I run an equality check on the struct, it once again behaves as though my values have shifted.

For example, I am trying to downcast Model A to ModelProtocol. var m = Model A and has the values {id: "1234", name: "Cal"}. When I downcast, m now has the values { id:"", name:"1234" }.

After downcasting an array of structs, my Variables View window shows that all of the values in my struct have shifted "down" (will explain in a second). But when I print(structName), the values are fine. However, when I run an equality check on the struct, it once again behaves as though my values have shifted.

For example, I am trying to downcast Model A to ModelProtocol. var m = Model A and has the values {id: "1234", name: "Cal"}. When I downcast, m now has the values { id:"", name:"1234" }.

Actual Example Below:

Models that I want to downcast:

struct PrivateSchoolModel: Decodable, SchoolProtocol {

    var id: String

    var name: String

    var city: String

    var state: String

}



struct PublicSchoolModel: Decodable, SchoolProtocol {

    var id: String

    var name: String

    var city: String

    var state: String  

    var latitude: String

    var longitude: String

}

Protocol I want to downcast to:

protocol SchoolProtocol {

    var id: String { get set }

    var name: String { get set }

    var city: String { get set }

    var state: String { get set }

    var longitude: Float { get set }

    var latitude: Float { get set }

}



extension SchoolProtocol {

    var longitude: Float {

        get { return -1.0 }

        set {}

    }

    var latitude: Float {

        get { return -1.0 }

        set {}

    }

}

Downcasting:

guard let downcastedArr = privateSchoolArray as? [SchoolProtocol] else { return  }

Result (item at index 0) or originalArr:

id = "1234"

name = "Leo High School"

city = "Bellview"

state = "WA"

Result (item at index 0) of downcastedArr:

id = ""

name = "1234"

city = "Leo High School"

state = "Bellview"

But if I print(downcastArr[0]), it will show:

id = "1234"

name = "Leo High School"

city = "Bellview"

state = "WA"

But if I try originalArray[0].id == downcastArr[0].id, it returns false

My Code with the problem:

class SchoolJSONHandler {

    private enum JSONFile: String {

        case publicSchool = "publicSchool"

        case privateSchool = "privateSchool"

    }



    private lazy var privateSchoolArray = getPrivateSchools()

    private lazy var publicSchoolArray = getPublicSchools()



    func getSchoolArray(sorted: Bool, filtered: Bool, by stateAbbreviation: String?) -> [SchoolProtocol] {

        var schools = combineArrays()



        if sorted {

            schools.sort(by: { $0.name < $1.name })

        }



        if filtered {

            guard let abbr = stateAbbreviation else { return  }

            schools = schools.filter {

                return $0.state == abbr

            }

        }



        return schools

    }



    private func combineArrays() -> [SchoolProtocol] {

        // EVERYTHING IS FINE IN NEXT LINE

        let a = privateSchoolArray

        // PROBLEM OCCURS IN NEXT 2 LINES WHEN DOWNCASTING

        let b = privateSchoolArray as [SchoolProtocol]

        let c = publicSchoolArray as [SchoolProtocol]

        return b + c

    }



    private func getPublicSchools() -> [PublicSchoolModel] {

        guard let jsonData = getJSONData(from: .publicSchool) else { return  }

        guard let schools = decode(jsonData: jsonData, using: [PublicSchoolModel].self) else { return  }

        return schools

    }



    private func getPrivateSchools() -> [PrivateSchoolModel] {

        guard let jsonData = getJSONData(from: .privateSchool) else { return  }

        guard let schools = decode(jsonData: jsonData, using: [PrivateSchoolModel].self) else { return  }

        return schools

    }



    private func getJSONData(from resource: JSONFile) -> Data? {

        let url = Bundle.main.url(forResource: resource.rawValue, withExtension: "json")!

        do {

            let jsonData = try Data(contentsOf: url)



            return jsonData

        }

        catch {

            print(error)

        }



        return nil

    }



    private func decode<M: Decodable>(jsonData: Data, using modelType: M.Type) -> M? {

        do {

            //here dataResponse received from a network request

            let decoder = JSONDecoder()

            let model = try decoder.decode(modelType, from:

                jsonData) //Decode JSON Response Data



            return model

        } catch let parsingError {

            print("Error", parsingError)

        }



        return nil

    }

}

And then it is just called in another class by schoolJSONHandler.getSchoolArray(sorted: true, filtered: true, by: "WA")