These tests for more rigor:

```
assert(uuid.validate('d9428888-122b-11e1-b85c-61cd3cbb3210') === true, 'Valid ID');
assert(uuid.validate('D9428888-122B-11E1-B85C-61CD3CBB3210') === true, 'Valid upper-case ID');
assert(uuid.validate('d9428888-122b-11e1-b85c-61cd3cbb321') === false, 'Too-long');
assert(uuid.validate('d9428888-122b-11e1-b85c-61cd3cbb32100') === false, 'Too-short');
assert(uuid.validate('d942888-8122b-11e1-b85c-61cd3cbb3210') === false, 'Bad hyphen-placement');
assert(uuid.validate('x9428888-122b-11e1-b85c-61cd3cbb3210') === false, 'Invalid hex digit');
assert(uuid.validate('d9428888-122b-01e1-b85c-61cd3cbb3210') === false, 'Bad version (0)');
assert(uuid.validate('d9428888-122b-61e1-b85c-61cd3cbb3210') === false, 'Bad version (6)');
assert(uuid.validate('d9428888-122b-11e1-785c-61cd3cbb3210') === false, 'Bad variant (0b01)');
assert(uuid.validate('d9428888-122b-11e1-c85c-61cd3cbb3210') === false, 'Bad variant (0b11)');
```