[clojure mode] Modernize the style of the example code.

[The Clojure Style Guide](https://github.com/bbatsov/clojure-style-guide).

Author: finalfantasia

mode/clojure/index.html

@@ -27,63 +27,60 @@
 <article>
 <h2>Clojure mode</h2>
 <form><textarea id="code" name="code">
-; Conway's Game of Life, based on the work of:
-;; Laurent Petit https://gist.github.com/1200343
-;; Christophe Grand http://clj-me.cgrand.net/2011/08/19/conways-game-of-life
+(ns game-of-life
+  "Conway's Game of Life, based on the work of
+  Christophe Grand (http://clj-me.cgrand.net/2011/08/19/conways-game-of-life)
+  and Laurent Petit (https://gist.github.com/1200343).")
 
-(ns ^{:doc "Conway's Game of Life."}
- game-of-life)
+;;; Core game of life's algorithm functions
 
-;; Core game of life's algorithm functions
-
-(defn neighbours
-  "Given a cell's coordinates, returns the coordinates of its neighbours."
+(defn neighbors
+  "Given a cell's coordinates `[x y]`, returns the coordinates of its
+  neighbors."
   [[x y]]
-  (for [dx [-1 0 1] dy (if (zero? dx) [-1 1] [-1 0 1])]
+  (for [dx [-1 0 1]
+        dy (if (zero? dx)
+             [-1 1]
+             [-1 0 1])]
     [(+ dx x) (+ dy y)]))
 
 (defn step
-  "Given a set of living cells, computes the new set of living cells."
+  "Given a set of living `cells`, computes the new set of living cells."
   [cells]
-  (set (for [[cell n] (frequencies (mapcat neighbours cells))
-             :when (or (= n 3) (and (= n 2) (cells cell)))]
+  (set (for [[cell n] (frequencies (mapcat neighbors cells))
+             :when (or (= n 3)
+                       (and (= n 2)
+                            (cells cell)))]
          cell)))
 
-;; Utility methods for displaying game on a text terminal
-
-(defn print-board
-  "Prints a board on *out*, representing a step in the game."
-  [board w h]
-  (doseq [x (range (inc w)) y (range (inc h))]
-    (if (= y 0) (print "\n"))
-    (print (if (board [x y]) "[X]" " . "))))
-
-(defn display-grids
-  "Prints a squence of boards on *out*, representing several steps."
+;;; Utility methods for displaying game on a text terminal
+
+(defn print-grid
+  "Prints a `grid` of `w` columns and `h` rows, on *out*, representing a
+  step in the game."
+  [grid w h]
+  (doseq [x (range (inc w))
+          y (range (inc h))]
+    (when (= y 0) (println))
+    (print (if (grid [x y])
+             "[X]"
+             " . "))))
+
+(defn print-grids
+  "Prints a sequence of `grids` of `w` columns and `h` rows on *out*,
+  representing several steps."
   [grids w h]
-  (doseq [board grids]
-    (print-board board w h)
-    (print "\n")))
-
-;; Launches an example board
-
-(def
-  ^{:doc "board represents the initial set of living cells"}
-   board #{[2 1] [2 2] [2 3]})
-
-(display-grids (take 3 (iterate step board)) 5 5)
+  (doseq [grid grids]
+    (print-grid grid w h)
+    (println)))
 
-;; Let's play with characters
-(println \1 \a \# \\
-         \" \( \newline
-         \} \" \space
-         \tab \return \backspace
-         \u1000 \uAaAa \u9F9F)
+;;; Launches an example grid
 
-;; Let's play with numbers
-(+ 1 -1 1/2 -1/2 -0.5 0.5)
+(def grid
+  "`grid` represents the initial set of living cells"
+  #{[2 1] [2 2] [2 3]})
 
-</textarea></form>
+(print-grids (take 3 (iterate step grid)) 5 5)</textarea></form>
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