Book Image

Learn Scala Programming

By : Slava Schmidt
Book Image

Learn Scala Programming

By: Slava Schmidt

Overview of this book

The second version of Scala has undergone multiple changes to support features and library implementations. Scala 2.13, with its main focus on modularizing the standard library and simplifying collections, brings with it a host of updates. Learn Scala Programming addresses both technical and architectural changes to the redesigned standard library and collections, along with covering in-depth type systems and first-level support for functions. You will discover how to leverage implicits as a primary mechanism for building type classes and look at different ways to test Scala code. You will also learn about abstract building blocks used in functional programming, giving you sufficient understanding to pick and use any existing functional programming library out there. In the concluding chapters, you will explore reactive programming by covering the Akka framework and reactive streams. By the end of this book, you will have built microservices and learned to implement them with the Scala and Lagom framework.
Table of Contents (19 chapters)


This was an intense chapter. We learned about the concept of working with effects in a way that the knowledge of the effects' structure is outsourced to another abstraction. We looked at three such abstractions.

The Functor allows us to apply a function of one argument to each element stored in the container.

The Applicative (or applicative functor) extends the Functor in a way that it is possible to apply a function of two arguments (and by induction, functions of any number of arguments). We’ve seen that it is possible to choose one of three equally valid sets of primitives that define applicative and derive all of the other methods from these primitives.

We said that this approach of defining a minimal set of primitive functions and the rest of functionality in terms of these primitives is a common approach in functional programming.

The last abstraction...