Create OptionSet from JSON in Swift

OptionSetStringIntializing.swift

public protocol OptionSetStringIntializing {
    init?(_ stringValue: String)
}

public extension OptionSet {
    
    static func decode<T>(from strings: [String]) -> T where T: OptionSet, T: OptionSetStringIntializing {
        var options: T = []
        
        strings.forEach { (str) in
            if let option = T(str) {
                options.formUnion(option)
            }
        }
        return options
    }
}

extension String.CompareOptions: OptionSetStringIntializing {
    private enum StrCompareOptions: String {
        case caseInsensitive
        case backwards
    }
    
    public init?(_ stringValue: String) {
        switch stringValue {
        case StrCompareOptions.caseInsensitive.rawValue:
            self = .caseInsensitive
        case StrCompareOptions.backwards.rawValue:
            self = .backwards
        default:
            return nil
        }
    }
}

//Example
let jsonArray = ["caseInsensitive", "backwards"]
let options: String.CompareOptions = String.CompareOptions.decode(from: jsonArray)

options.contains(.caseInsensitive) // true
options.contains(.backwards) // true
options.contains(.anchored) // false