Codable/Decodable should decode Array with Strings

Question

Why is the names Array not decoding?

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import Foundation

struct Country : Decodable {
         


        

Answer 1

You have defined names as an optional property of Country. If your intention is that this key may not be present in the JSON then use decodeIfPresent:

extension Country {
    public init(from decoder: Decoder) throws {
        let values = try decoder.container(keyedBy: CodingKeys.self)
        names = try values.decodeIfPresent([String].self, forKey: .names)
    }
}

This method returns nil if the container does not have a value associated with key, or if the value is null.

But actually you can just omit your custom init(from decoder: Decoder) implementation (and the enum CodingKeys), because that is the default behaviour and will be synthesized automatically.

Remark: An implicit variable error is defined in any catch clause, so

} catch {
    print(error.localizedDescription)
}

can be more informative than just a print("error") (although not in this particular case).