Question

I read in the backbone documentation that calling collection.reset() clears the collection. I want to know if it removes the models as well or do they continue to live in memory?

If they’re not removed is there an easier way to remove all the models in a collection without iterating through the models and calling model.remove()?

Answer 1

What you are looking for is, probably, for the models to be garbage-collected. That is, that nobody has a reference to these models anymore, after they are removed from the collection.

Backbone does its part of removing the references that it set on the models, when they are removed from the collection. However, you have to do your own cleanup if your code has references to those models. Most of the time, this happens if those models are registered as event listeners, like in this example: http://jsfiddle.net/dira/4uxp4/2/

Taking a look at the implementation of reset, you could change _removeReference to call a cleanup function on the model as well. And in the model, remove the model from all the listeners/all the other objects that keep a reference to it.