Book Image

Mastering Functional Programming

Book Image

Mastering Functional Programming

Overview of this book

Functional programming is a paradigm specifically designed to deal with the complexity of software development in large projects. It helps developers to keep track of the interdependencies in the code base and changes in its state in runtime. Mastering Functional Programming provides detailed coverage of how to apply the right abstractions to reduce code complexity, so that it is easy to read and understand. Complete with explanations of essential concepts, practical examples, and self-assessment questions, the book begins by covering the basics such as what lambdas are and how to write declarative code with the help of functions. It then moves on to concepts such as pure functions and type classes, the problems they aim to solve, and how to use them in real-world scenarios. You’ll also explore some of the more advanced patterns in the world of functional programming such as monad transformers and Tagless Final. In the concluding chapters, you’ll be introduced to the actor model, which you can implement in modern functional languages, and delve into parallel programming. By the end of the book, you will be able to apply the concepts of functional programming and object-oriented programming (OOP)in order to build robust applications.
Table of Contents (17 chapters)

Problem statement

In this chapter, we will be addressing the problem of building a web crawler. Web crawlers are important, for example, in the domain of indexing and searching the web.

The graph structure of the web

All the websites can be imagined as a graph of pages. Every page contains some HTML markup and content. As part of this content, most web pages contain links to other pages. Since links are supposed to take you from one page to another, we can visualize the web as a graph. We can visualize links as edges that take you from one node to another node.

Given such a model for the entire internet, it's possible to address the problem of searching for information over the web:

We are talking about a problem that...