Question

I’m working on a backbone project with underscore (1.3.0). Underscore has a shuffle method that shuffles

create a collection

countries = new Countries
child

check length

countries.length
0

fetch the data (using an underscore method, fetch)

 countries.fetch();
    Object
XHR finished loading: "http://localhost:3000/countries". jquery.js:8215

Now it has a length of four

  countries.length
    4

try to return a randomly shuffled array
countries.shuffle();
TypeError: Object [object Object] has no method ‘shuffle’

shuffle otherwise works in my environment

   _.shuffle([1, 2, 3, 4, 5, 6]);
[2, 1, 4, 5, 6, 3]

I watched Ryan Bates backbone railscast, and he essentially does the same thing but his works. One difference, though, was when he created his Collection object, it had a different return value

entries = new Raffler.Collections.Entries()
entries #return value

However, when I create a collection, it returns ‘child’

 countries = new Countries
    child

But I don’t see that making a difference because I’m still able to call countries.fetch(); which is an underscore method.

Any suggestions?

Answer 1

You might be using an old version of Backbone, or a version of underscore that’s not compatible with your version of Backbone.

The first version of Backbone to include the Collection.shuffle method was 0.9.0. The documentation in those days did not specify the minimum version for underscore, but for Backbone 0.9.1 the minimum was > 1.3.1. For the current Backbone release (0.9.9) it’s > 1.4.3.

Also, fetch is not an underscore method.