Collection & Model Mixin

[megawac]

Adds Collection & Model mixins for adding custom implementations of iterator/check methods to base collection and model. The main motivation of this is to add some lodash methods that were missing on the prototype.

Ideally one could do

Backbone.Collection.mixin({
  sum: lodash.sum,
  take: lodash.take
});

However, I don't have a good idea of how to support iteratees, so things like collection.sum('value')

Thoughts? /cc @akre54 @jridgewell

[jridgewell]

However, I don't have a good idea of how to support iteratees, so things like collection.sum('value')

Hm? You seem to have it already.

[megawac]

Does it? I just assumed it wouldn't get transformed to a (attr) => model.get(attr) as it doesn't hit this case as length != 3 or 4

[Florian-R]

Curious to know why you've used an array of array here instead of an array of object here, e.g:

_.each([
   {base:Collection, methods: collectionMethods, attribute: 'models'},
   {base:Model,  methods: modelMethods, attribute: 'attributes'}
], function(config) {

[megawac]

No real reason, I don't see a major advantage for either strategy at the moment. Though current impl it lends itself nicely to _.spread if underscore ever decides to follow suit

[jridgewell]

I just assumed it wouldn't get transformed to a (attr) => model.get(attr) as it doesn't hit this case as length != 3 or 4

Oh, didn't read that case. What fails if we use cb for every case?

[megawac]

I think _.invoke would fail in addition to omit, difference, union and friends, and perhaps the reduce implementations

[rafde]

how has this not been merged yet?

[linus-amg]

@rafde maybe you can take a look at backbone-metal, i think its something similar

https://github.com/marionettejs/backbone-metal

[rafde]

this PR is suppose to allow you to define your own functions that would proxy against model.attributes && collection.models

backbone-metal doesn't look like it offers the same feature.

[megawac]

Can I get another set of 👀 on this? Want to get it into #4028

[akre54]

Fine by me 👍