Getting started on Clojure

One of my task last week is to write Tic Tac Toe in Clojure. Seeing code like this, of course I freaked out:

	(defn play [x o]
	(letfn [(player [mark] (if (= :x mark) x o))]
	(loop [mark :x board empty-board history []]
	(show-board *view* board)
	(let [opponent (opponent mark)]
	(cond
	(win-for? opponent board) {:winner opponent :board board :history history}
	(draw? board) {:winner nil :board board :history history}
	:else (let [m (move (player mark) board)]
	(if (nil? (board m))
	(do (show-message *view* (format "%s takes %s\n" mark m))
	(recur opponent (assoc board m mark) (conj history m)))
	(recur mark board history))))))))

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I have no idea what it is saying. If I don't understand it, I didn't like it! I want to crawl back to Ruby. Ruby is much more English-like and way easier to read. It doesn't have a million parenthesis like Clojure. However, after spending a whole week in Clojure, I hate to admit it, but I'm beginning to like it. I like how easy it is to do a lot of things. For example, if I want to say get a total of a few numbers, this is all I have to write:

(+ 1 2 3 4 5)

Ruby

 1 + 2 + 3 + 4 + 5

In this example, I have to say Clojure wins on account of simplicity. It is easy to read and write this statement. I don't know if you can get any easier than this.

Enough background, here is how I would have started to learn Clojure:

1. Blackstag - It is a really simple guide to get you started. You will not learn everything you need, but it's a good place to start. (I skipped installation because it's already installed on my computer so I'm not sure if it's still relevant.)
2. Clojure API - I read most of the methods in here. It will help you become familiar with what Clojure has to offer.
3. Roman Numerals Kata - Write your own roman numeral kata. I looked at others to see how they do it. Look up keywords that you don't understand.
4. Read other people code. I look at several Clojure implementations of TicTacToe because mainly I have to write it. But it really helps because I have an idea of how the game is suppose to work. That is not to say I read and understand everything I read. Anyway, here's a list of Github you want to checkout:
1. Rylan Tic Tac Toe
2. Micah
3. Colin
4. Wai Lee
5. Clojure Cookbook - I didn't look at it, but it sounds promising.
5. Clojure Docs - This is my best friend once I got an idea of what function I want to call. 

Note: I recommend using Emacs with rainbow parenthesis when you write Clojure code. If you are writing in Clojure, it is worth the time and effort to learn how to use Emacs. 

I got most of my Clojure Tic Tac Toe code done by reading Blackstag, Clojure API, and others code. I am much more comfortable with the language now.