We ended the last section by examining some sample code after it had been made production-quality by adding correct error handling techniques. In this section, we'll dig into the most common Swift error handling techniques, which will help ensure all the code you develop in Swift will be robust and of high quality.

Swift supports many of the same error handling techniques available in other object-oriented languages, such as C++, Java, and C#. Functions—either your own or standard library functions—often return error codes as integers, error types, and Boolean variables. In addition, Swift provides exception handling using the do…catch construction, which is functionally equivalent to the try…catch construction used in many other languages.