Dates

Plain Backbone

• No nested models
• No support for Date type
• No subviews

Basics

Native properties

• are created for default model attributes
• explicitly declared for Model and Collection
• serve as calculated properties
• direct support for lazy evaluation pattern

Lazy initialization

var C = Nested.Collection.extend({
    properties : {
        index : function(){
            if( !this._index ){
                this._index = new Index( this );

                this.listenTo( this, 'change add remove reset', function(){
                    this._index.rebuild( this );
                });
            }

            return this._index;
        }
    }
});



var c = new C(); // no index at this point...

if( c.index.has( 'name' ) ){ // c.index is created 
    ...
}

Model.defaults

var UserInfo = NestedTypes.Model.extend({
   defaults : {
       name : 'test'
    }
});

Model.Collection

• is created automatically for every Model
• can be customized with Model.collection property
• is inherited from the base model's Collection

var UserInfo = NestedTypes.Model.extend({
   defaults : {
       name : 'test'
    }
});

​var users = new UserInfo.Collection();

Model.properties

• explicit native properties definition
• overrides auto-generated native properties
• also works for Collection

Class type

• has backbone-style .extend and .initialize
• can have native properties (Class.properties)
• can trigger and listen to backbone events

Run-time errors

• Attributes must be defined in defaults.
• Model.set argument must be literal JS object.
• Native properties cannot override base class methods.

Type Annotations

Example: handling the Date

var User = Nested.Model.extend({
    defaults : {
        created    : Date,
        name       : "",
        loginCount : 0
    }
});

• On new User() - it creates the Date object.
• On user.set and user.fetch() - it parse ISO UTC+0 dates from strings, integer timestamps, and MS timestamps.
• On user.save() - it serialize model.created to ISO UTC+0 datetime string.

Type specs...

• ...are as simple as just mentioning value's constructor in Model.defaults.
• ...is the guarantee that attribute always holds value of designated type, or null.
• ...free you from writing custom .parse() and .toJSON() in most situations.

Constructor Type Spec

var A = Nested.Model.extend({
    defaults : {
        a : Ctor,
        b : Ctor.value( null ),

        c : Ctor.value( "something" )
    }
});

Primitive Types

var A = Nested.Model.extend({
    defaults : {
        str : "",
        num : 0,

        bool: false,
        int : Integer.value( 5 )
    }
});

var DetailedUserInfo = UserInfo.extend({
    urlBase : '/api/detailed_user/',

    defaults : {
        login : '',
        roles : [ 'user' ]
    },

    collection : {
        initialize : function(){
            this.fetch();
        }
    }
});