set.js

var HashSet = function() {
    this.initializer();
};

HashSet.PRESENT = {};

HashSet.prototype = {
    _map: null,

    initializer: function() {
        var instance = this;

        A.EventTarget.call(this, {emitFacade:true});

        instance._map = new A.Map();
        instance.publish({
            add: { defaultFn: instance._defAddFn },
            clear: { defaultFn: instance._defClearFn },
            remove: { defaultFn: instance._defRemoveFn }
        });
    },

    add: function(value) {
        this.fire('add', { value: value });
    },

    clear: function() {
        this.fire('clear');
    },

    has: function(value) {
        return this._map.has(value);
    },

    isEmpty: function() {
        return this._map.isEmpty();
    },

    remove: function(value) {
        this.fire('remove', { value: value });
    },

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

    values: function() {
        return this._map.keys();
    },

    _defAddFn: function(event) {
        this._map.put(event.value, HashSet.PRESENT);
    },

    _defClearFn: function() {
        this._map.clear();
    },

    _defRemoveFn: function(event) {
        var instance = this,
            map = instance._map,
            value = map.remove(event.value);

        event.removed = (value === HashSet.PRESENT);
    }
};

A.Set = HashSet;
A.augment(A.Set, A.EventTarget);