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iOS Error Handling in Swift Error Handling Handling Errors

Sara Worth
Sara Worth
5,225 Points
Posted by Sara Worth
Sara Worth
5,225 Points

Not sure why this isn't passing?

I'm getting the error: "If the key does not exist, make sure to throw the InvalidKey error." I'm pretty sure I've done that so I'm not sure what's wrong.

error.swift 
enum ParserError: Error {
  case emptyDictionary
  case invalidKey
}

struct Parser {
  var data: [String : String?]?

  func parse() throws {
    guard (data?.keys.contains("someKey")) != nil else {
            throw ParserError.invalidKey
        }

        guard (data?["someKey"]) != nil else {
            throw ParserError.emptyDictionary
        }
  }
}

let data: [String : String?]? = ["someKey": nil]
let parser = Parser(data: data)

1 Answer

Chase Marchione
Chase Marchione
155,055 Points
Chase Marchione
Chase Marchione
155,055 Points

Interestingly enough, the challenge passes if the equality operator is set to equals for the first guard statement. 

guard (data?.keys.contains("someKey")) == nil else {

Curious stuff, but hope this helps in the meanwhile!