How to use the right methods to right types

Enums+Extensions.swift

// Common - Portuguese - pt-BR.lproj/Localizable.strings
// "common.change" = "Mudar";
// "common.error" = "Erro";
// "common.delete" = "Exluir";
// "common.wait" = "Aguarde";

// Common - English - en.lproj/Localizable.strings
// "common.change" = "Change";
// "common.error" = "Error";
// "common.delete" = "Delete";
// "common.wait" = "Wait";


// MARK: - Project Constants
enum Project {
    
    // Image Names
    enum Images {
        enum Checkout: String, ImageRepresentable {
            case first  = "icon-first-image"
            case second = "icon-second-image"
        }
    }

    // Localizable Strings
    enum Localizable {
        
        // Common
        enum Common: String, LocalizeRepresentable {
            case change     = "common.change"
            case error      = "common.error"
            case delete     = "common.delete"
            case wait       = "common.wait"
        }
    }
}


// MARK: - Representable Protocols
protocol ImageRepresentable: RawRepresentable {
    var image: UIImage? { get }
}

protocol LocalizeRepresentable: RawRepresentable {
    var localized: String { get }
}


// MARK: - Representable Protocols Extensions
extension ImageRepresentable where RawValue == String {
    var image: UIImage? {
        return UIImage(named: rawValue)
    }
}

extension LocalizeRepresentable where RawValue == String {
    var localized: String {
        return NSLocalizedString(rawValue, comment: "")
    }
}