Backbone collection: Retrieve distinct values of a collection

backbone.js, underscore.js

Solution

You can use pluck and then use uniq (example: http://jsfiddle.net/sCVyN/5/)

pluck

A convenient version of what is perhaps the most common use-case for map: extracting a list of property values.

uniq

Produces a duplicate-free version of the array, using `===` to test object equality. If you know in advance that the array is sorted, passing true for isSorted will run a much faster algorithm. If you want to compute unique items based on a transformation, pass an iterator function.

Problem

I have backbone collection of models and would like to retrieve the distinct values of a certain property If I have loaded data like the following into my collection: ``` [{brand:'audi',id:'1234'}, {brand:'audi',id:'3456'}, {brand:'bmw',id:'3456'}] ``` I would now want to get the distinct brands from the collection. The result should be: ``` ['audi','bmw'] ``` Looking at the Backbone and Underscore API I don't see anything obvious to achieve this. My current approach would be to use a library like jslinq Am I missing anything obvious or does somebody have a better suggestion than jslinq?

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