code: function xor() {
  	var args = [].slice.call(arguments),
  		bits = args.shift().slice();
  	args.forEach(function(arg, y) {
  		arg.forEach(function(bit, x) {
  			bits[x] ^= bit;
  		});
  	});
  	return bits;
  }
docs: /* exclusive or all arguments (arrays of bits)