Bracket Mess

JSCocoa will soon get an Objective-J like syntax, mixing Javascript syntax and Objective-C messaging :
// Allocate a new object
var a = [MyObject new]

Mixing both styles looks buggy but is actually correct :

// Make a new array containing a new object
var array = [[MyObject new]]
// Make a new array containing an alloc'ed object, get that object, call init on it, save it in its own array
var obj = [[[MyObject alloc]][0] init]
// (This gets translated as var obj = [MyObject.alloc][0].init

After your object is initialized, you can use Javascript-like access for hashes and dictionaries :

// Allocate a new object as the only element of an array immediate, init it, 
// then gets it 'keys' properties, then the 'name' property of 'keys'
var obj = [[[[MyObject alloc]][0] init] keys]['name']

JSCocoa will translate Javascript array and hash immediates to NSArray and NSDictionary instances, so they can also be used as parameter values ...

var o = [[MyObject alloc] initWithOptions: { orientation : 'vertical', count : 5 }]

or to retrieve an instance to call on to :

// Call a method from an object stored in a js array
var array = [MyObject new, MyObject new]
[array[0] doSomething]

// Call a method from an object stored in a js hash
var hash = { 'value' : [MyObject new] }
[hash['value'] doSomethingElse]
I'm only using these as stress test, no code needs that many brackets !

2009 09 25

This looks remarkably like the Objective-J code used for the Cappuccino framework. Are you doing something similar?

Patrick Geiller
2009 09 28

Yes, I'm following the Objective-J and JSTalk route.

Extending Javascript this way seems like a good idea.

Follow me on Twitter
Planet Cocoa

2011 02 22Distance field
2010 07 202Binding through NSApp
2010 05 122Forwarding invocations
2010 02 272Core Image black fringes
2010 02 21Quickest Way to Shell
2010 02 08Who's calling ?
2009 09 2138 ways to use Blocks in Snow Leopard
2009 08 182Bracket Mess
2009 08 124Taming JavascriptCore within and without WebView
2009 04 15Debugging with Activity Monitor
2009 03 25How Core Image Color Tracking works
2009 03 1510Custom NSThemeFrame
2009 03 10Which framework is running ?
2009 03 074CoreUI can paint pretty big
2009 02 18Localization with functions
2009 01 30Did you forget to nest alloc and init?
2009 01 16JSCocoa on the iPhone
2009 01 11Mixing WebView and JavascriptCore
2009 01 09Badge overflow
2009 01 09Find your Garbage Collection leaks with Instruments

Powered by MediaWiki