Conway's Game of Life in Clojure

conway.clj

(ns conway.core
	(:require [clojure.set :refer [intersection]]))


(defn neighbours [[x y]]
	(for [i [-1 0 1] j [-1 0 1] :when (not= i j 0)]
		[(x + i) (y + j)]))

(defn alive-next-gen [board cell]
	(let [alive-neighbours (intersection board (neighbours cell))
		  alive (board cell)]
		(cond
			(and alive (< alive-neighbours 2)) false ; underpopulation
			(and alive (= 2 alive-neighbours)) true
			(and alive (> alive-neighbours 3)) ; overpopulation
			(= 3 alive-neighbours) true ; birth
			false
			)))

(defn game [board]
	(let [board-neighbours (map neighbours board)]
		(filter (partial alive-next-gen board) board-neighbours)))

; board is a set of cells, e.g.: #{[1 0] [2 3]}

conway_test.clj

(ns conway.core-test
  (:require [clojure.test :refer :all]
            [conway.core :refer :all]))

(deftest board-test
  (testing "blinker"
  	(let [board #{[1 0] [1 1] [1 2]}]
  		(is (game board) #{[1 1] [2 1] [0 1]})
  		(is (game (game board)) board)))

  (testing "block"
  	(let [board #{[0 1] [1 1] [1 0] [0 0]}]
  		(is (game board) board))))