GiorgioE GiorgioE - 1 month ago 15
Swift Question

Error when getting value from constant : Ambiguous reference to member 'subscript'

I am using

with value of enum case. I've trouble with getting value from [String: String] constant.

I don't know how to fix it, it has to be a trap, but I don't know where, as the
is surely string:

enum DictTypes : String {
case settings
case options
case locations
enum FileTypes : String {
case json
case pList

func getCodebookUrlComponent() -> String
var FileSpecs: (
dictType: DictTypes,
fileType: FileTypes,
redownload: Bool
) = (.settings, .json, true)

let codebooks = [
"settings" : "settings",
"options" : "options"

let key = self.FileSpecs.dictType // settings or options

if let urlComponent = codebooks[key] {

return urlComponent

return ""

This line
if let urlComponent = codebooks[key]
comes with an error:

Ambiguous reference to member 'subscript'


You should use .rawValue for this case :

if let urlComponent = codebooks[key.rawValue]{
   return urlComponent

This problem occurs because of the let key = self.FileSpecs.dictType in this line you receive key that is FileSpecs type. And subscript that is implemented in the Array will not conform for that value type.

rawValue in you're case return String value that you assign in you're enum.