Codable Improvements and Refinements

[ahti (Lukas Stabe 🙃)]

There has been some talk about that (and why it's kind of difficult) here:

Automatic Codable conformance for enums with associated values that themselves conform to Codable

At least as of Swift 4.1, an enum with one or more cases with associated values cannot participate in synthesized Codable conformance. For example, the following will yield compiler errors: enum MyOtherEnum: Codable { // errors: does not conform to Encodable/Decodable case foo case bar(label: Int) } This is true even if all the associated values in said enum themselves conform to Codable. In a similar fashion as the synthesized Hashable / Equatable implementations for enums with associ…

Imo this is one of the limitations for which a solution would really benefit from custom attributes to allow the user to express how exactly their enum cases and associated values should be en/decoded.