I am working on a Swift service that stores codable types in JSON. The type also defines a nested CodingKeys enum to define the property names when coded to JSON. For example, I might have a type that looks like this:
struct MyType : Codable {
let myIntProperty: Int
let myStringProperty: String
enum CodingKeys: String, CodingKey {
case myIntProperty = "int_property"
case myStringProperty = "string_property"
}
}
Now I have a function that wants to operate on one of these properties, as specified by a key path to that property. Using the type from the example, I want a function that can be called like this:
let result = myFunc(usingProperty: \MyType.myIntProperty)
My function is declared using the KeyPath type:
func myFunc<T: Codable, G>(usingProperty: KeyPath<T, G>) -> G {
...
}
In order to implement my function, I would like to somehow get access to not just the key path parameter named usingProperty, but also to the coding key that it is associated with. So when called with the key path to the myIntProperty property, I would want to get the name used when encoding it, which is int_property.
Is there any way to derive this value from the KeyPath parameter and its root type's CodingKeys enumeration?
