Jack Diederich's implementation of Conway's "Game of Life"

gol.py

import itertools

def neighbors(point):
    x, y = point
    yield x + 1, y
    yield x - 1, y
    yield x, y + 1
    yield x, y - 1
    yield x + 1, y + 1
    yield x + 1, y - 1
    yield x - 1, y + 1
    yield x - 1, y - 1

def advance(board):
    newstate = set()
    recalc = board | set(itertools.chain(*map(neighbors, board)))
    for point in recalc:
        count = sum((neigh in board) for neigh in neighbors(point))
        if count == 3 or (count == 2 and point in board):
            newstate.add(point)
    return newstate

glider = set([(0,0), (1,0), (2, 0), (0,1), (1,2)])
for i in range(1000):
    glider = advance(glider)
    print glider