Property wrapper to turn empty collection into nil

EmptyToNil.swift

import Foundation

@propertyWrapper
struct EmptyToNil<WrappedType: Codable & Collection>: Codable {
    
    let wrappedValue: WrappedType?
    
    init(wrappedValue: WrappedType?) {
        self.wrappedValue = wrappedValue
    }
    
    init(from decoder: Decoder) throws {
        let container = try decoder.singleValueContainer()
        guard let value = try? container.decode(WrappedType.self) else {
            wrappedValue = nil
            return
        }
        wrappedValue = value.isEmpty ? nil : value
    }
    
    func encode(to encoder: Encoder) throws {
        try wrappedValue.encode(to: encoder)
    }
    
}