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TooTallNate/NodObjC

The Node.js ⇆ Objective-C bridge

TooTallNate/NodObjC.json
{
"createdAt": "2011-07-11T05:26:09Z",
"defaultBranch": "master",
"description": "The Node.js ⇆ Objective-C bridge",
"fullName": "TooTallNate/NodObjC",
"homepage": "http://tootallnate.github.io/NodObjC",
"language": "JavaScript",
"name": "NodObjC",
"pushedAt": "2020-08-08T20:07:00Z",
"stargazersCount": 1419,
"topics": [],
"updatedAt": "2025-11-27T02:14:45Z",
"url": "https://github.com/TooTallNate/NodObjC"
}

The [Node.js][] ⇆ [Objective-C][ObjCWikipedia] bridge

Section titled “The [Node.js][] ⇆ [Objective-C][ObjCWikipedia] bridge”

Build Status

NodObjC exposes the Objective-C runtime to [Node.js][] in a high-level, easy to use fashion. It uses the BridgeSupport files to dynamically generate an API from an Objective-C “Framework”, and uses the node ffi module to dynamically interact with the Objective-C runtime.

Essentially, NodObjC is similar in nature to the other popular Objective-C scripting bridges:

  • [JSCocoa][]
  • [PyObjC][]
  • [MacRuby][]
  • [And the others…][others]

So you can write entire Cocoa or iOS GUI applications entirely in Node.js JavaScript! Applications are interpreted at runtime through the V8 engine, rather than (pre)compiled to a (binary) machine exectuable. This has the advantage of being able to tweak code without having to recompile; excellent for rapid prototyping and development (or for those GUI applications where absolute speed is not a requirement, i.e. most). So what are you waiting for? Get to coding!

Install using npm, of course!

Terminal window
$ npm install nodobjc

Or add it to the "dependencies" section of your package.json file.

var $ = require('nodobjc')
// First you import the "Foundation" framework
$.framework('Foundation')
// Setup the recommended NSAutoreleasePool instance
var pool = $.NSAutoreleasePool('alloc')('init')
// NSStrings and JavaScript Strings are distinct objects, you must create an
// NSString from a JS String when an Objective-C class method requires one.
var string = $.NSString('stringWithUTF8String', 'Hello Objective-C World!')
// Print out the contents (toString() ends up calling [string description])
console.log(string)
// → Prints "Hello Objective-C World!"
pool('drain')

Be sure to check out the [full API docs][docs].

This module offers a bi-directional bridge between Node.js and the Objective-C runtime. What does that mean exactly? Well due to the design of the Objective-C runtime, it is possible to port the entire API to other languages. There are quite a few bridges for Obj-C so one for node was a necessity.

So with this module, you get access to all of the Objective-C APIs, but you invoke them through JavaScript. Obj-C has a concept of “message passing” to invoke methods on objects. The way that you pass messages around is probably a little bit different than the kind of JavaScript you’re used to:

// In JavaScript, you invoke a function on an object like:
obj.func(arg)

Compared to:

// In NodObjC, you send a message to an object like:
obj('func', arg)

In Objective-C, the names of methods are part of the arguments that you pass along:

[array insertObject: obj
atIndex: 5]

The equivalent of the above message invocation in NodObjC syntax would be:

array('insertObject', obj,
'atIndex', 5)

So the even numbered arguments are the parts of the method name that will be invoked, and the odd numbered arguments are the Obj-C arguments themselves. In the above example, the insertObject:atIndex: function will be invoked.

In NodObjC, not only is the Objective-C runtime exposed, but so are the corresponding C functions that usually go along with these APIs (thanks to BridgeSupport). So for example, we can make an NSRect by calling the NSMakeRect() C function:

$.NSMakeRect(5, 10, 8, 30)
// -> NSRect struct

There’s a plethora of other Objective-C resources and tutorials out there.

You should definitely have Apple’s official [Mac][MacDev] or [iOS][iOSDev] API docs handy at all times.

If you’re looking for support for developing with/for NodObjC you might want to join the [mailing list][group], and check out the [#nodobjc][IRC] channel in the Freenode IRC server.

Additional topics of discussion can be found on the [Wiki][] page.

[docs] !: http://tootallnate.github.io/NodObjC [group] !: https://groups.google.com/d/forum/nodobjc [Node.js] !: http://nodejs.org [JSCocoa] !: http://inexdo.com/JSCocoa [PyObjC] !: http://pyobjc.sourceforge.net [MacRuby] !: http://macruby.org [IRC] !: http://webchat.freenode.net/?channels=nodobjc [Wiki] !: https://github.com/TooTallNate/NodObjC/wiki [MacDev] !: http://developer.apple.com/library/mac/navigation/ [iOSDev] !: http://developer.apple.com/library/ios/navigation/ [ObjCWikipedia] !: http://en.wikipedia.org/wiki/Objective-C [others] !: http://cocoadev.com/CocoaBridges