Is the order addons receive events predictable?

[bsmorgan]

If multiple addons register for the same event (i.e. MAIL_INBOX_UPDATE) can the order of delivery be predicted? Is it the same as the order in which they registered?

Thanks!

[Lombra]

Originally Posted by bsmorgan Is it the same as the order in which they registered?

As far as I know, yes.

[Phanx]

It's undefined. So, it works the same way as iterating over a table with pairs -- you might get the same order consistently, but it's not guaranteed. For an addon you plan to publish, you shouldn't depend on it. If you need to make sure your event handler always runs after another addon's event hander, use a hook.

[bsmorgan]

Thanks for the answers.

As it turns out, MAIL_INBOX_UPDATE fires so many times that it doesn't matter which addon sees it first. My addon needs to know if a mail is new and who sent it. Those two values become valid in different MAIL_INBOX_UPDATE events.

I had to hook GetInboxText (which sets wasRead) to keep track of new mail if some other addon reads the message before the sender is valid. Once I know which mails are new, I can defer processing them until the sender is valid.

[Lombra]

Originally Posted by Phanx It's undefined. So, it works the same way as iterating over a table with pairs -- you might get the same order consistently, but it's not guaranteed. For an addon you plan to publish, you shouldn't depend on it. If you need to make sure your event handler always runs after another addon's event hander, use a hook.

Is that really a fact? I can not recall my assumption ever having failed me before.

[Torhal]

It depends on the event(s), really. Safer to just assume they're all unreliable.