4 ms·

Obviously I'm interpreting "correctly generated" to mean "generated in accordance with the RFC", so no, it does not.

• derefr 11y ago
  "Correctly generated" also means, at the very least, "useful to the people implementing it." If you can't use a given UUID implementation without generating collisions in the first 100 items, you won't use that UUID implementation. There's an "implicit spec" behind each spec of what people will or won't actually bother to do. Generating correlated v4 UUIDs isn't wrong, but it is stupid in the sense of being self-defeating: nobody who wants to generate v4 UUIDs wants them with insufficient randomness, and will have no reason to not consider a bad random-number source to be a bug, because it's interfering with getting them the thing they want to get by generating v4 UUIDs in the first place. (The real point of the explicit UUID spec, meanwhile, is in saying what constitutes a valid UUID—and it's certainly valid to generate a UUIDv4 using insufficient entropy. There's no way for a peer receiving such UUIDs to guess that they're maybe-predictable-with-enough-effort and reject them on that basis, which is all "validity" can ever mean: what can or cannot be technically enforced by protocol peers.)