Swift 6: Precision in Error Handling With Typed Throws Feature

Elevate Your Error Handling: Mastering Typed Throws in Swift 6

Brahim Siempay
3 min readJun 26, 2024

Swift 6 introduces a powerful new feature: typed throws. This enhancement allows functions to specify which errors they can throw, leading to more precise error handling, improved code clarity, and enhanced safety. Let’s explore how this feature works and why it’s a game-changer for Swift developers.

What Are Typed Throws?

In previous versions of Swift, functions that could throw errors did not specify what types of errors they might throw. This often led to less clarity in error handling, as any error type could potentially be thrown, requiring extensive use of generic error handling mechanisms.

Swift 6 changes this by allowing functions to declare specific error types. This means you can now define which exact errors a function is capable of throwing, providing greater precision and control over your error handling logic.

Example Without Typed Throws

enum NetworkError: Error {
case badURL
case requestFailed
}

func fetchData(from url: String) throws {
guard url == "validURL" else {
throw NetworkError.badURL
}
// Fetch data logic
}

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