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best practices for ambiguous reference when using Swift's protocol extensions with associated types

πŸ‘€ Views: 0 πŸ’¬ Answers: 1 πŸ“… Created: 2025-06-12
swift protocols associated-types

I'm sure I'm missing something obvious here, but Can someone help me understand I'm stuck on something that should probably be simple. I'm working on a Swift project where I have two protocols with associated types, and I'm implementing a common protocol extension for both. However, I'm running into an ambiguity behavior when trying to call methods from this extension. The behavior message states: `Ambiguous reference to member '...'`, and I'm not sure how to resolve it. Here’s the relevant part of my code: ```swift protocol Vehicle { associatedtype EngineType func startEngine() -> EngineType } protocol ElectricVehicle: Vehicle { func charge() -> String } protocol GasVehicle: Vehicle { func refuel() -> String } extension Vehicle { func vehicleInfo() -> String { return "This is a vehicle." } } struct Tesla: ElectricVehicle { typealias EngineType = String func startEngine() -> String { return "Electric engine started" } func charge() -> String { return "Charging..." } } struct Ford: GasVehicle { typealias EngineType = String func startEngine() -> String { return "Gas engine started" } func refuel() -> String { return "Refueling..." } } let myTesla = Tesla() print(myTesla.vehicleInfo()) print(myTesla.startEngine()) ``` When I run this code, I get the ambiguity behavior when I try to call `myTesla.vehicleInfo()` or when I attempt to create an instance of `Tesla` and call methods from both protocols. I am following the correct guidelines for using associated types, so I'm puzzled about why this is happening. I've also tried to give explicit type hints, but that hasn't resolved the scenario. Any insights into how to fix this ambiguity would be greatly appreciated! For context: I'm using Swift on Linux. What's the best practice here? I recently upgraded to Swift LTS. Cheers for any assistance!