Making a variable from if statement global

Question

While encoding JSON, I´m unwrapping stuff with an if let statement, but I'd like to make a variable globally available

do {
  if
    let json = try JSONSerialization.jsonObject(with: data) as? [String: String], 
    let jsonIsExistant = json["isExistant"] 
  {
    // Here I would like to make jsonIsExistant globally available
  }

Is this even possible? If it isn't, I could make an if statement inside of this one, but I don't think that would be clever or even possible.

Answer 1

delclare jsonIsExistant at the place you want it. If you are making an iOS App, than above viewDidLoad() create the variable

var jsonIsExistant: String?

then at this point use it

do {
    if let json = try JSONSerialization.jsonObject(with: data) as? [String: String], 
    let tempJsonIsExistant = json["isExistant"] {
        jsonIsExistant = tempJsonIsExistant
    }
}

This could be rewritten like so though

do {
    if let json = try JSONSerialization.jsonObject(with: data) as? [String: String] { 
        jsonIsExistant = json["isExistant"]
    }
} catch {
    //handle error
}

If handled the second way, then you have to check if jsonIsExistant is nil before use, or you could unwrap it immediately with a ! if you are sure it will always have a field "isExistant" every time that it succeeds at becoming json.