Question

I have this model –

class pt.SearchResultModel extends Backbone.Model
  defaults:
    id:"",
    image:"",
    colour:""

I am trying this –

_.pluck(resultsCollection,'id')

But it keeps returning undefined – not sure what’s going on.

What syntax error am I making?

Answer 1

The Underscore array methods are embedded (so to speak) into Backbone collections. You can call them directly on them:

resultsCollection.pluck 'id'

In most of the cases you could also use the Underscore methods over the collection’s models attribute (which is a plain-old array), like _.pluck someCollection.models, 'someAttr', but notice that the case of pluck is special, as Backbone models will usually not have their attributes as own properties (you have to call get to access them). The implementation of Backbone’s pluck is very straightforward nevertheless 🙂