Little readability note:

$net->train_set([
  [1,1], [0,1],
  [1,0], [0,1],
  [0,1], [0,1],
  [0,0], [1,0],
], 10000);
[download]

Since the arrayrefs on the left and right columns are associated, the above might be better as:

$net->train_set([
  [1,1] => [0,1],
  [1,0] => [0,1],
  [0,1] => [0,1],
  [0,0] => [1,0],
], 10000);
[download]