![]() ![]() The source code for this lesson is available at github.Once I cover those, you’ll be close to being able to write small, simple, functional applications with everything I’ve covered so far. It’s worth mentioning that case classes also provide decent, default toString method implementations. Also, we have all getters defined by default. (You’ll see even more reasons to use case classes as you go along.)Īs mentioned, I write about lenses later in the book, when we get to a point where we have to “update as you copy” complicated objects.īut for now the next thing we need to dig into is for comprehensions. Similarly to the data class in Kotlin, Scala’s case class has automatically defined hashcode and equals methods. The copy method is just one reason for this, but it’s a good reason. As you can imagine, from here on out you’re going to be using case classes more than you’ll use the default Scala class.The way you do this in Scala is with the copy method, which comes with Scala case classes. ![]() Because functional programmers don’t mutate objects, when an object needs to be updated it’s necessary to follow a pattern which I describe as “update as you copy”.I cover lenses in a lesson later in this book. The general idea of these libraries is known as a “lens” (or “lenses”), and they make copying nested objects much simpler. But fear not: there are Scala/FP libraries that make this easier. The examples I just showed are a simplification of the code and description found at these URLs:Īs you saw, the “update as you copy” technique gets more complicated when you deal with real-world, nested objects, and the deeper the nesting gets, the more complicated the problem becomes. In each case, users should refer to the definitions of each individual scale for guidance on the dimensions of risk covered in each assessment. (More on this after the attribution.) Attribution These examples show how the “update as you copy” process works with nested objects in Scala/FP. ![]() You can shorten that code if you want, but I show the individual steps so it’s easier to read. Val hannah4 = py(billingInfo = BillingInfo(newCCs)) ![]()
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