Book Image

Mastering Clojure

By : Akhil Wali
Book Image

Mastering Clojure

By: Akhil Wali

Overview of this book

Clojure is a general-purpose language from the Lisp family with an emphasis on functional programming. It has some interesting concepts and features such as immutability, gradual typing, thread-safe concurrency primitives, and macro-based metaprogramming, which makes it a great choice to create modern, performant, and scalable applications. Mastering Clojure gives you an insight into the nitty-gritty details and more advanced features of the Clojure programming language to create more scalable, maintainable, and elegant applications. You’ll start off by learning the details of sequences, concurrency primitives, and macros. Packed with a lot of examples, you’ll get a walkthrough on orchestrating concurrency and parallelism, which will help you understand Clojure reducers, and we’ll walk through composing transducers so you know about functional composition and process transformation inside out. We also explain how reducers and transducers can be used to handle data in a more performant manner. Later on, we describe how Clojure also supports other programming paradigms such as pure functional programming and logic programming. Furthermore, you’ll level up your skills by taking advantage of Clojure's powerful macro system. Parallel, asynchronous, and reactive programming techniques are also described in detail. Lastly, we’ll show you how to test and troubleshoot your code to speed up your development cycles and allow you to deploy the code faster.
Table of Contents (19 chapters)
Mastering Clojure
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
References
Index

Managing concurrent tasks


Clojure has a couple of handy constructs that allow us to define concurrent tasks. A thread is the most elementary abstraction of a task that runs in the background. In the formal sense, a thread is simply a sequence of instructions that can be scheduled for execution. A task that runs in the background of a program is said to execute on a separate thread. Threads will be scheduled for execution on a specific processor by the underlying operating system. Most modern operating systems allow a process to have several threads of execution. The technique of managing multiple threads in a single process is termed as multithreading.

While Clojure does support the use of threads, concurrent tasks can be modeled in more elegant ways using other constructs. Let's explore the different ways in which we can define concurrent tasks.

Note

The following examples can be found in src/m_clj/c2/concurrent.clj of the book's source code.

Using delays

A delay can be used to define a task...