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object - Get codable's property names as strings in swift

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let disucssionMessageTimestampKey = DiscussionMessage.CodingKeys.messageTimestamp.stringValue gives an error:

'CodingKeys' is inaccessible due to 'private' protection level


I have a message structure defined like this:

struct DiscussionMessage: Codable {
    let message, userCountryCode, userCountryEmoji, userName, userEmailAddress: String
    let messageTimestamp: Double
    let fcmToken, question, recordingUrl, profilePictureUrl: String?
}

I want to define a variable disucssionMessageTimestampKey whose value will be messageTimestamp. I want to use disucssionMessageTimestampKey variable in the following query:

messagesReference.queryOrdered(byChild: "messageTimestamp").queryStarting(atValue: NSDate().timeIntervalSince1970).observe(.childAdded)

So that I don't have to hardcode the string value ("messageTimestamp") of the variable name.

Now I know I could just do let disucssionMessageTimestampKey: String = "messageTimestamp". But this is again prone to errors. So I was wondering if there was a way that I could get the string value messageTimestamp without having to define it anywhere.

By something like this (I know this won't work but just to give an idea of what I am looking for)

let disucssionMessageTimestampKey: String = String(describing: DiscussionMessage.messageTimestamp) // Will store disucssionMessageTimestampKey = "messageTimestamp"

Also, would it be possible to completely define the key values first as strings and then use those as variable names in the actual codable object? I.e. first define let disucssionMessageTimestampKey: String = "messageTimestamp", and then use the variable disucssionMessageTimestampKey to define what the property (messageTimestamp) of the codable object should be called. (This is low priority but curious and seems related to the question at hand)

question from:https://stackoverflow.com/questions/65952289/get-codables-property-names-as-strings-in-swift

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