Book Image

Hands-On Functional Programming in Rust

By : Andrew Johnson
Book Image

Hands-On Functional Programming in Rust

By: Andrew Johnson

Overview of this book

Functional programming allows developers to divide programs into smaller, reusable components that ease the creation, testing, and maintenance of software as a whole. Combined with the power of Rust, you can develop robust and scalable applications that fulfill modern day software requirements. This book will help you discover all the Rust features that can be used to build software in a functional way. We begin with a brief comparison of the functional and object-oriented approach to different problems and patterns. We then quickly look at the patterns of control flow, data the abstractions of these unique to functional programming. The next part covers how to create functional apps in Rust; mutability and ownership, which are exclusive to Rust, are also discussed. Pure functions are examined next and you'll master closures, their various types, and currying. We also look at implementing concurrency through functional design principles and metaprogramming using macros. Finally, we look at best practices for debugging and optimization. By the end of the book, you will be familiar with the functional approach of programming and will be able to use these techniques on a daily basis.
Table of Contents (12 chapters)

Using functional design for concurrency

Concurrency forces the programmer to be more careful about information sharing. This difficulty coincidentally encourages good functional programming practices, such as immutable data and pure functions; when computation is not context-sensitive, it tends to also be thread-safe.

Functional programming sounds great for concurrency, but are there downsides?

In one example of good intentions with bad effects, during development of a functional language called Haskell, the development team (https://www.infoq.com/interviews/armstrong-peyton-jones-erlang-haskell) wanted to make programs run faster using concurrency. Due to a unique trait of the Haskell language, it was possible to run all expressions and sub-expressions in new threads. The development team thought this sounded great and tested it out.

The result was that more time was spent spawning...