marick

;;; Based on an idea by Paul Blair and Michael Nicholaides @nicholaides

(def *horizontal-blinker* [ [0,1] [1,1], [2,1] ]    )
(def *vertical-blinker*   [       [1,2]
                                  [1,1]
                                  [1,0]  ])

(example "of blinkers blinking"
    (next-world *horizontal-blinker*) => *vertical-blinker*
    (next-world *vertical-blinker*) => *horizontal-blinker*

marick

(def *horizontal-blinker* [ [0,1] [1,1], [2,1] ]    )

(def *vertical-blinker*   [       [1,2]
                                  [1,1]
                                  [1,0]  ])

(example "of blinkers blinking"
    (next-world *horizontal-blinker*) => *vertical-blinker*
    (next-world *vertical-blinker*) => *horizontal-blinker*
)

marick

(pending border tick unborder)

(defn next-world [world]
  (-> world
      border tick unborder)
)

marick

(defn next-world [world]
  (unborder (tick (border world))))

marick

    (f ...cell...) => 10
      (provided  
        (g ...cell...) => true
	(h ...cell...) => 2)

marick

    (living? (successor ...cell...) => falsey
      (provided 
        (living? ...cell...) => true
	(living-neighbor-count ...cell...) => 0)

marick

    (successor ...cell...) =means=> (killed ...cell...)   ;;; fix
      (provided 
        (living? ...cell...) => true
	(living-neighbor-count ...cell...) => 0)

marick

cell = mock()
# expectations
cell.should_receive(:living?).at_least.once.and_return(true)
cell.should_receive(:living_neighbor_count).at_least_once.and_return(0)
cell.should_receive(:killed).at_least.once

# run test
cell.successor

marick

(defn tick [bordered-world]
  (against-background [world bordered-world]
     (map successor bordered-world))
)

marick

(know "rules that determine the life or death of a cell in the sucessor generation"
    (successor ...cell...) =means=> (killed ...cell...)
      (provided  ; underpopulation
        (living? ...cell...) => true
	(living-neighbor-count ...cell...) =from=> [0, 1])
      (or ; overpopulation
        (living? ...cell...) => true
	(living-neighbor-count ...cell...) =from=> [4 ,,, 8]) 
      (or ; not enough cells to bring to life
        (living? ...cell...) => false