The Case for Clojure

Background

At NFJS shows, a common question is "I only have time to learn one new language on the JVM: which should I pick?".

The easy answer is true: it doesn't matter. Just pick one already!

However, I think people can reasonably ask for more information.

Even though my personal favourite is Groovy, I fancy that, like a good law professor, I could argue a decent case for any of them.

In this post, I'll write a bit on Clojure. To be honest, the title is deceiving: I don't know Clojure, and this isn't a full-blown legal case. I'm really inviting you to some resources (see below).

However, I know enough to see the benefit. This is an earnest post.

Mark Volkmann is giving a Clojure talk on Thursday at the St Louis JUG. Quoting from his intro, Clojure is a dynamically-typed, functional programming language that runs on the JVM.

From past talks, and from Mark's intro, here are some reasons I think Clojure is worthy of your consideration:

Let's Lisp Again, Like We Did Last Semester

If you liked Lisp back in university, welcome back: Clojure has a Lisp-like syntax and style. Both the syntax and functional programming seems new again, in part thanks to Stuart Halloway's book.

Here, 'new' means a shot-in-the-arm to the FP community and a welcoming online scene. Let's face it: it can be lonely when studying older languages.

Got Lisp?

If you don't know Lisp or functional programming, adding Clojure to your repetoire is almost like right-brain thinking. It is profoundly different from Java, C#, and other imperative languages. This is important in order to truly grow. To borrow from natural languages: it's cool if you know French and Spanish, but it's cooler if you know French and Chinese (or Spanish and Chinese).

Bonus: though not unique to FP, Clojure can execute data as code. This is powerful, and quite underrated, IMHO. This goes all the way back to grand-daddy Lisp, so you'll be learning from one of the undisputed giants. What's more both Lisp and Clojure have a minimal, consistent syntax. Though it is, er, mind-expanding at first, many people become true fans of the philosophy.

Software Transactional Memory

Concurrency is the new memory management. Memory management was a beast until garbage collection evolved, over decades, to be a shining sword.

Now, on the JVM, we've tamed the memory beast and wrestle with concurrency. Consider books like this: JCiP is an outstanding book, but it is a tough go, in part because the developer must coordinate lock-level tools. Or, worse, a team of people must coordinate lock-level tools.

What if we had something really different -- a pseudo-intelligent agent like a garbage collector, except aimed at concurrency? That's what Clojure offers: a unique alternative that might (and that's all we can say: might) slay the beast of our time.

The Upshot

Come on out to the JUG on Thursday, or if you aren't in St Louis, check out Mark's excellent article on Clojure. It is quite thorough, and has received kudos from the Clojure community.