##Introduction In the Computer Science world we often talk about the value of Separation of Concerns (SoC). This Wikipedia article on the subject says that well-separated code is more modular, maintainable, and reusable. The basic idea is that we separate our code into components by their roles so that those pieces can be used and developed independently as well as assembled into a greater whole.

However, I am concerned with the traditional treatment of concerns. We often look at concerns as a breakdown of our application into various interconnected pieces, or objects. For example, you might have a game program with a rendering system, an input system, a physics system, and so on. A spreadsheet application might have concerns regarding computations, persistence, and input. At a high level, and borrowing from the Wikipedia article, you might have concerns for things like business logic, persistence, data access, and presentation.

##Introduction One of my favorite features of Clojure is the way changes in application state are handled. In Clojure we separate the concerns of our data (which is stored as values) and the management of how that data might change over time. Contrast this to most other languages that have mutable state tied to their object model at some level.

There are four state management primitives. Here's a very simple example of each and how they behave.

Introduction

I recently decided to write a Snake game in Clojure as a small project. In the game you have a snake that grows as it consumes food. The goal of the game is to make the snake as long as possible without self-intersecting. I got the idea to do it on a Saturday morning and by that night I was done. Most of the coding was done in the evening since I was doing family activities all day. All told, this was probably a 3 hour project. The entire program is 75 lines of code. That's awesome! This includes both the JVM and JavaScript targets via Clojure and ClojureScript. Here's the game:

Introduction

Recently I was reading this article regarding what is (or was) new in Java 8 and took an interest in the following section on Lambdas:

Introduction

I've been coding in Clojure for over a year now and not everything is unicorns and rainbows. Whatever language you choose will affect how you think and work and Clojure is no different. Read on to see what some of these effects are and why you might want to reconsider learning Clojure.