monaco-editor/website/index/samples/sample.clojure.txt

54 lines
1.4 KiB
Plaintext

(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).")
;;; Core game of life's algorithm functions
(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])]
[(+ dx x) (+ dy y)]))
(defn step
"Given a set of living `cells`, computes the new set of living cells."
[cells]
(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-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 [grid grids]
(print-grid grid w h)
(println)))
;;; Launches an example grid
(def grid
"`grid` represents the initial set of living cells"
#{[2 1] [2 2] [2 3]})
(print-grids (take 3 (iterate step grid)) 5 5)