UnionOfRAD/lithium — pull request #528 by nervetattoo (2012-06-06 20:43:19+00:00)
Title: Implements Collection::reduce

The duo `map` and `each` just lacked `reduce` to make it easier for functional programming style in Lithium.
The need for stuff like this should not be uncommon:

```php
$profit = Invoices::all()->reduce(function($memo, $model) {
return $memo + $model->sum;
}, 0);
```