If you add a space after the + also, it’ll be fine (indeed, better).

But to be honest, I hate code that tries to do 5 bits of logic on one 100-character-long line, instead of just breaking into two more readable lines. [Edit: looks like that was fixed in the version at http://willbailey.name/conway/docs/conway.html]

Also, can’t your isAlive function look like:

  isAlive: (row, col) -> @world[row]?[col]?.live