Error handling in Swift 2
Languages such as Java and C# generally refer to the error handling process as exception handling; within the Swift documentation, Apple refers to this process as error handling. While on the outside, the Java and C# exception handling may look very similar to Swift's error handling, there are some significant differences that those familiar with exception handling in the other language will notice throughout this chapter.
Representing errors
Before we can really understand how error handling works in Swift, we must first see how we would represent an error. In Swift, errors are represented by values of types that conform to the ErrorType protocol. Swift's enums are very well-suited to modeling the error conditions because generally, we have a finite number of error conditions to represent.
Let's look at how we would use an enum to represent an error. For this, we will define a fictitious error named MyError with three error conditions: Minor, Bad, and Terrible:
enum...