yiisoft/yii2 — pull request #259 by creocoder (2013-05-14 13:10:30+00:00)
Title: [Suggestion] ActiveCollection

This will allow to do:

```
$valid = $models->validate();
```

instead of

```
$valid = true;
foreach ($models as $model) {
$valid = $model->validate() && $valid;
}
```

This will allow to do:

```
$success = $models->save();
```

instead of

```
$success = true;
foreach ($models as $model) {
$success = $model->save() && $success ;
}
```

This allow to do:

```
$models->populate($_POST);
```

Also there can be other useful methods that work with collection. This addition allow to be DRY and KISS.