amd-utils array methods to mimic ES6 Set

functional.js

// how amd-utils Array methods can be used instead of the ES6 Set
// http://www.nczonline.net/blog/2012/09/25/ecmascript-6-collections-part-1-sets/
// http://millermedeiros.github.com/amd-utils/array.html

define(
    [
        'amd-utils/array/insert',
        'amd-utils/array/remove',
        'amd-utils/array/contains'
    ],
    function (insert, remove, contains) {

        var items = [];

        insert(items, 5);
        insert(items, "5");
        insert(items, 5); // duplicate is ignored

        console.log(items); // [5, "5"]

        console.log( contains(items, 5) ); // true
        remove(items, 5);
        console.log( contains(items, 5) ); // false

        console.log(items); // ["5"]

    }
);

Set.js

// If OOP is "your thing" it can be easily abstracted into a constructor

define(
    [
        'amd-utils/array/insert',
        'amd-utils/array/remove',
        'amd-utils/array/contains',
        'amd-utils/array/forEach'
    ],
    function (insert, remove, contains, forEach) {

        function SetCollection(items){
            this._items = [];
            items.unshift(this._items);
            insert.apply(null, items);
        }

        SetCollection.prototype = {

            add : function(val){
                insert(this._items, val);
            },

            // renamed `delete` to `remove` since `delete` is a bad name
            remove : function(val){
                remove(this._items, val);
            },

            has : function(val){
                return contains(this._items, val);
            },

            size : function(){
                return this._items.length;
            },

            // added `forEach` for convenience since `for` loops won't work
            forEach : function(cb, thisObj){
                forEach(this._items, cb, thisObj);
            }

        };

        return SetCollection;

    }
);

Used this gist to enhance my comment on Nicholas Zakas post: http://www.nczonline.net/blog/2012/09/25/ecmascript-6-collections-part-1-sets/#comment-17622