Book Image

Hands-On Functional Programming with TypeScript

By : Remo H. Jansen
Book Image

Hands-On Functional Programming with TypeScript

By: Remo H. Jansen

Overview of this book

Functional programming is a powerful programming paradigm that can help you to write better code. However, learning functional programming can be complicated, and the existing literature is often too complex for beginners. This book is an approachable introduction to functional programming and reactive programming with TypeScript for readers without previous experience in functional programming with JavaScript, TypeScript , or any other programming language. The book will help you understand the pros, cons, and core principles of functional programming in TypeScript. It will explain higher order functions, referential transparency, functional composition, and monads with the help of effective code examples. Using TypeScript as a functional programming language, you’ll also be able to brush up on your knowledge of applying functional programming techniques, including currying, laziness, and immutability, to real-world scenarios. By the end of this book, you will be confident when it comes to using core functional and reactive programming techniques to help you build effective applications with TypeScript.
Table of Contents (14 chapters)
5
The Runtime – Closures and Prototypes

Mastering Functions

In Chapter 1, Functional Programming Fundamentals, we learned about some of the most fundamental functional programming concepts. Functions are one of the fundamental building blocks of any TypeScript application, and they are powerful enough to warrant an entire chapter being dedicated to them in order to explore their potential.

In this chapter, we are going to master the usage of functions. The chapter starts with a quick recap of a number of basic concepts and then moves on to some less commonly known function features and use cases:

  • Function types:
    • Function declarations and function expressions
    • Named and anonymous functions
  • Working with parameters:
    • Functions with optional parameters
    • Functions with default parameters
    • Functions with rest parameters
    • Function overloading
    • Specialized overloading signature
  • Function scope
  • Immediately-invoked functions
  • ...