Question

I’m trying to use CoffeeScript with Backbone.js (via Brunch) and I want to implement a save function in my model, but it refuses to compile and I have been unable to figure out why. I need to both pass parameters into the save function and implement callbacks.

The code below gives an Unexpected ':' error on the second line, but I’m not sure why:

class exports.Tag extends Backbone.model

  defaults:
    id: null
    tagId: null
    found: false
    location: "Not yet found..."
    finders: []
    pointValue: 0
    unlockCode: ""

  verifyCode = ( code ) ->
    @save { tagId: @get 'tagId', unlockCode: code },
      success: ( model, response ) ->
        @trigger 'verifySuccessful', response
      error: ( model, response ) ->
        @trigger 'verifyFailed', response

Any help appreciated…thanks!

Answer 1

It’s here, you are confusing the parser

@save { tagId: @get 'tagId', unlockCode: code },

Is that this?

@save { tagId: @get('tagId'), unlockCode: code },

Or this?

@save { tagId: @get('tagId', unlockCode: code) },

Either will fix the error, but they obviously mean different things.

And might I add, implicit parens are indeed awesome, but take advantage of that awesome only in the most simple of circumstances. A rule I usually use is that omit parens for the first function invocation in a line, and use them for all others. This rule would have saved you from this issue entirely.