angularJS $on event handler trigger order

Question

I was wondering two things, in the context of angularJS event handling.

1. How is defined the order in which handlers listening to the same event are triggered?

Answer 1

To provide an answer to #2 (because I think @Stewie's answer to #1 is a really good one), while I'd hesitate to ever offer conclusive rules that say, "if you see this, then it's bad code", I would offer to say that if you have two event handlers, and one can only execute after the other has run: you should evaluate why that is the case and if you couldn't better encapsulate or organize the way your logic executes.

One of the primary use cases of pub/sub event broadcasting/listening is to allow separate components that are fully independent of one another to operate on their domain of influence in an independent way asynchronously. By one handler having to operate only after another handler has run first you are removing the asynchronous nature of pub/sub by adding a secondary requirement (though possibly necessary).

If it's an absolutely necessary dependency, then no: it's not a symptom of bad design - its a symptom of the requirements of that feature.