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iOS Error Handling in Swift Error Handling Handling Errors

how to call parse method in try/catch block?

I can't seem to know how to call parse method in try/catch block. Any assistance with this challenge is greatly appreciated.

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

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

  func parse() throws {
    guard let data = data else {
      throw ParserError.emptyDictionary
    }

    guard data["someKey"] != nil else {
      throw ParserError.invalidKey
    }
  }
}

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

do {

  } catch ParserError.emptyDictionary {
    print("empty dictionary") 
}
Jason Marcial
Jason Marcial
8,162 Points

Hi Noe, In order to call the parse method for this challenge, you'll achieve it using 'try' before calling the method, since parse() is a throwing function.

do {
    try parser.parse()
} catch ParserError.emptyDictionary {
    print("empty dictionary")
} catch ParserError.invalidKey {
    print("invalid key")
}

I hope this code finds helpful ?

Yes, that did it. Now, I'm not sure how to pattern match on specific error to display better error message. Again, your assistance is greatly appreciated.