single_success.swift

let single = Single<Int>.just(0)

// AS IS 
single.subscribe(onSuccess: { value in
    print("Got a value:", value)
}, onFailure: { error in
    print("Got a error:", error)
}, onDisposed: {

}).disposed(by: disposeBag)

// Prints
Got a value: 0


// TO BE 
Task {
    do {
        let value = try await single.value
        print("Got a value:", value)
    } catch {
        print("Got a error:", error)
    }
}
// Prints
Got a value: 0