How to remove elements from an Ember.ArrayController - ember.js

Question

In JavaScript, one can remove selected elements from an array by traversing it in reverse order and using splice(index, 1) to remove undesired elements. I'm trying to figure out how to do the same thing in Ember.js (without Ember Data).
I have an ArrayController and the associated Route's model function simply returns a JavaScript array. There an action in the controller, along the following lines:
removeElements: function () {
var i, arr = this.get('content'),
i = arr.length;
while (i) {
i -= 1;
if (arr[i].get('flag')) {
array.replace(i, 1);
}
}
This first appears to work in the browser. For example, if I have three elements and mark the first and third to be removed, the browser will leave the second item displayed. However, if I later try to mark the latter, Ember complains with Uncaught Error: Can't remove an item that has never been added.
I used replace() because Ember arrays don't have a splice method, but the docs also say that replace must be implemented in order to be used, but I don't quite understand where I'm supposed to implement it and I haven't found any sample implementations to guide me.
I've also tried various other methods, such as removeObject, removeObjects and more, but none did what I need.

Answer 1

You'd need to create your own array collection and implement replace on that collection (probably extending Ember.Array to get you started).
removeObject should work just fine (granted a little inefficient, though if the size of this list is small it's negligible):
removeElements: function () {
var controller = this,
list = this.toArray();
list.forEach(function(item){
if(item.get('flag')){
controller.removeObject(item);
}
});
}
using removeAt should give you the results you're looking for
removeElements: function () {
var i = this.get('length');
while (i--) {
if (this.objectAt(i).get('flag')) {
this.removeAt(i);
}
}
}