Why is functional programming useful? Functional programming constructs have popped up in all major programming languages in the past decade. Programmers have enjoyed their benefits—simplified loops, more expressive code, and simple parallelization. But there's more to it—decoupling from time, enabling opportunities to remove duplication, composability, and a simpler design. Higher adoption of functional programming (including the large-scale adoption of Scala in the financial sector) means more opportunities for you once you know and understand it. While we will take a deep dive into functional programming in this book to help you learn, remember that functional programming is another tool to add to your toolbox—one that you can choose to use when the problem and the context fits.
The following topics will be covered in this chapter:
- An introduction to functional programming and an examination of how you've already been using functional constructs
- Structured loops versus functional loops
- Immutability
- Object-oriented programming (OOP) versus functional design
- Composability and removing duplication