    public init(_ string: String) {
        enum ParsingState {
            case readingScheme
            case readingHost
            case readingPort
            case readingPath
            case readingQuery
            case finished
        }
        var scheme: HBParser?
        var host: HBParser?
        var port: HBParser?
        var path: HBParser?
        var query: HBParser?
        var state: ParsingState = .readingScheme