Generic type not preserved when called within another generic function
[Updated with a less contrived example]
I'm trying to extend a generic function to provide different behavior for a specific type. This works as expected when I call the function directly. But If I call it from within another generic function, the original generic type is not preserved and I get the default behavior. I'm a bit new to Swift, so I may be missing something obvious here.
My code looks something like this:
protocol Task {
associatedtype Result
}
struct SpecificTask: Task {
typealias Result = String
// other taks related properties
}
enum TaskRunner<T: Task> {
static func run(task: T) throws -> T.Result {
// Task not supported
throw SomeError.error
}
}
extension TaskRunner where T == SpecificTask {
static func run(task: T) throws -> T.Result {
// execute a SpecificTask
return "Some Result"
}
}
func run<T: Task>(task: T) throws -> T.Result {
// Additional logic related to running the task
return try TaskRunner.run(task: task)
}
print(try TaskRunner.run(task: SpecificTask())) // Prints "Some Result"
print(try run(task: SpecificTask())) // Throws SomeError
I need the top-level run function to call the SpecificTask version of the lower-level run() function, but the generic version of the function is called instead
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