god.erl

module GameOfLife where
import [Enum, Access]

neighbours(x,y, state) ->
  [{nx, ny} || nx <- -1..1, ny <- -1..1]
  |> reduce(0, ({nx, ny}, acc) -> (state[x + nx][y + ny] || 0) + acc)

alive(1, n) -> if n in 2..3, do: 1, else: 0
alive(0, n) -> if n == 3, do: 1, else: 0

step(state) ->
    [{x, y, val} || {x, row} <- state, {y, val} <- row]
    |> reduce(state, {x, y, val}, acc -> put_in acc, [key(x), key(y)], (neighbours(x,y, state) |> alive(val)))

gof.ex

defmodule GameOfLife do
  import Enum
  import Access
  def neighbours(x,y, state) do
    (for nx <- -1..1, ny <- -1..1, do: {nx, ny})
    |> reduce(0, fn {nx, ny}, acc -> (state[x + nx][y + ny] || 0) + acc end)
  end

  def alive(1, n), do a: if n in 2..3, do: 1, else: 0
  def alive(0, n), do: if n == 3, do: 1, else: 0

  def step(state) do
    (for {x, row} <- state, {y, val} <- row, do: {x,y,val})
    |> reduce(state, fn {x, y, val}, acc -> put_in acc, [key(x), key(y)], (neighbours(x,y, state) |> alive(val)) end)
  end
end