Readied actions, AoO and cancelling attacks

[Legildur]

Gee, maybe I've been playing this wrong, but I would have thought that Y's attack on Z was interrupted (by the Ready action) by X. That is, Y's attack is done with unless Y has multiple attacks (either from either fighting with two-weapons, Haste, or iterative attacks), in which case he could use his remaining attack(s) to continue to attack Z (or, for that matter, X).

Although, on reading the SRD on the Ready action (combined with Hypersmurf's post) I can see why it may be a little vague:

If the triggered action is part of another character’s activities, you interrupt the other character. Assuming he is still capable of doing so, he continues his actions once you complete your readied action.

So I'm not sure if he interrupts Y and prevents the attack continuing or interrupts Y and Y continues afterwards with Quickdraw and attack?

 

[Artoomis]

"Y" cannot now decide he did not want to attack X after all and avoid the AoO - that would cause a paradox where the AoO should not happen because the attack did not happen, but the AoO already DID happen.

The attack has been interrupted and Y has no weapon.

Y may continue the attack, if possible (unarmed, maybe or maybe using quickdraw to pull out another weapon) OR may lose that attack and continue his turn.