@discardableResult public func get<Response>( _ path: PathComponent..., use closure: @escaping (Request) throws -> Response ) -> Route where Response: ResponseEncodable { return self.on(.GET, path, use: closure) } @discardableResult public func get<Response>( _ path: PathComponent..., use closure: @escaping (Request) throws -> Response ) -> Route where Response: ResponseEncodable { return self.on(.GET, path, use: closure) }Response は型パラメータ名だけど、 同じ名前の Response 型 もある )