Structure and Interpretation of Computer Programmers

I make it easier and faster for you to write high-quality software.

Tuesday, July 29, 2008

Cocoa#, Mono and Me

My great application:


Yeah, OK, not so great. But this Inverse Hoffman is the result of a couple of hours hacking in Mono, with Cocoa#. My app’s largely based on the Stupid Word Counter tutorial, though it’s a from-scratch implementation of the famous Apple/NeXT sample application in C#.

Firstly, a little history. My first encounter with .NET was back in about 2003 at a Microsoft Developer Roadshow in the car park (and later lecture theatre) in Oxford’s comlab. I was particularly interested in their discussions of cross-platform capability, Project Rotor (I kept in touch with one of the Rotor developers) and so on, but really didn’t see much exciting in .NET. Nonetheless, being a fair man, I took my beta CDs of Windows 2003 and Visual Studio .NET and gave them a whirl. Unfortunately, still not much interesting. Largely due to buggy betas and a lack of beta documentation.

Now accessing Cocoa from non-ObjC languages is nothing new, we’ve been doing it from Perl, Python, Ruby and Java for ages and partcularly old farts might even remember Objective-Tcl. Why should I care about Cocoa#? Well for a start, there are likely to be a lot Windows developers out there with some (language that boils down to MS IL eventually) skills who are wanting to produce Mac applications, and it’d be interesting to see what we’ll end up with when they do. And it’s always fun to learn a new language, anyway ;-)

Good points

  • Real NIB files. No really, that interface is genuinely an IB 3.x NIB based on the Cocoa Application template. The objects inside it are Objective-C objects, and there are good old outlets and actions (I haven’t yet investigated whether Cocoa Bindings would work).
  • macpack. A command-line tool which takes your IL executable and wraps it up in a Cocoa application bundle, ready for drag-deployment.
  • Good inline bridging information. Unlike, say, PyObjC the language bridge isn’t completely dynamic, but unlike the Java bridge or JIGS you don’t have to keep a separate manual mapping of real classes onto ObjC shams. For instance, here’s the controller from Currency, complete with class, ivar and method exports:

namespace info.thaesofereode.CurrencyConverter
public partial class CurrencyConverterController : Cocoa.Object
public CurrencyConverterController(System.IntPtr native_object) : base(native_object) {}

//Cocoa IBOutlets
private Cocoa.TextField inputCurrency;
private Cocoa.TextField outputCurrency;
private Cocoa.TextField conversionRate;

//Cocoa IBAction
public void calculate(Cocoa.Object sender)
//get the rate from the view
System.String rate = conversionRate.Value;
CurrencyConverterModel.Rate = System.Convert.ToDouble(rate);
//get the currency
System.String input = inputCurrency.Value;
System.Double output = CurrencyConverterModel.convert(System.Convert.ToDouble(input));
//update the UI
outputCurrency.Value = System.Convert.ToString(output);

Bad points

  • Not very Cocoa-like wrapper classes. I think this is deliberate; they’ve gone for making the Cocoa shim look like a .NET interface because after all, we’re programming from .NET. This is a bit disappointing as I’m more familiar with PyObjC and the Perl-ObjC-Bridge where the APIs are left pointedly alone, but given the target audience of Cocoa# it’s unsurprising.
  • MonoDevelop. Luckily, using it isn’t mandated.

So, overall, one more good point than bad (and a tentative two, if you overlook MonoDevelop); a pretty good initial evaluation and I might give this a deeper scrape.

posted by Graham Lee at 23:40  

Tuesday, July 22, 2008


For a long time, I deliberately avoided microblogs like twitter. I thought that they were simply an acknowledgement that people want to be published more than they want to have something to say. However, it would be rude of me to completely disavow the medium without actually giving it a go.

To that end, I may indeed be iamleeg on twitter, as soon as twitter actually finishes processing the signup form.

I’d like to point out that one problem I’m going to have is brevity – I have spent 650 characters telling you what my username is. Constraining myself to SMS-sized wibblings will indeed be tricksy.

posted by Graham Lee at 22:33  

Monday, July 21, 2008

Common sense writ large

Looking at the bottom of Apple’s Q3 results, as indeed with any similar publication from a US publicly-traded company, we see the following text.

This press release contains forward-looking statements including without limitation those about the Company’s estimated revenue and earnings per share. These statements involve risks and uncertainties, and actual results may differ. Risks and uncertainties include without limitation potential litigation from the matters investigated by the special committee of the board of directors and the restatement of the Company’s consolidated financial statements; unfavorable results of other legal proceedings; the effect of competitive and economic factors, and the Company’s reaction to those factors, on consumer and business buying decisions with respect to the Company’s products; war, terrorism, public health issues, and other circumstances that could disrupt supply, delivery, or demand of products; continued competitive pressures in the marketplace; the Company’s reliance on sole service providers for iPhone in certain countries; the continued availability on acceptable terms of certain components and services essential to the Company’s business currently obtained by the Company from sole or limited sources; the ability of the Company to deliver to the marketplace and stimulate customer demand for new programs, products, and technological innovations on a timely basis; the effect that product transitions, changes in product pricing or mix, and/or increases in component costs could have on the Company’s gross margin; the effect that product quality problems could have on the Company’s sales and operating profits; the inventory risk associated with the Company’s need to order or commit to order product components in advance of customer orders; the effect that the Company’s dependency on manufacturing and logistics services provided by third parties may have on the quality, quantity or cost of products manufactured or services rendered; the Company’s dependency on the performance of distributors and other resellers of the Company’s products; the Company’s reliance on the availability of third-party digital content; and the potential impact of a finding that the Company has infringed on the intellectual property rights of others. More information on potential factors that could affect the Company’s financial results is included from time to time in the Company’s public reports filed with the SEC, including the Company’s Form 10-K for the fiscal year ended September 29, 2007; its Forms 10-Q for the quarters ended December 29, 2007 and March 29, 2008; and its Form 10-Q for the quarter ended June 28, 2008, to be filed with the SEC. The Company assumes no obligation to update any forward-looking statements or information, which speak as of their respective dates.

Erm, like, duh. Stuff which we say might happen in the future, might not actually happen. Really? You’ve got to get out of the financial industry, there’s a lucrative career ahead of you in construction.

posted by Graham Lee at 22:04  

Friday, July 18, 2008

Designing a secure Cocoa application

That’s the title of next month’s CocoaHeads Swindon, and I’ll be leading the presentation/discussion. So if you want to learn a little about how to ensuring your Cocoa app doesn’t give away the keys to the kingdom, or have some experiences to share with the rest of the group, come along! We’ll be at the Glue Pot, which is nice and near the train station as well as reasonably close to a car park. We’ll be congregating at 7:00 but will wait for everyone to be settled with a beer in their hand before starting ;-).

posted by Graham Lee at 21:56  

Monday, July 14, 2008

Ah, the sweet sound of my own voice

The title is a linky to the press release regarding the edition of Sophos Podcasts I recorded with Carole, and which has now (clearly) gone live. In it we mainly talk about the data theft and Macs technical paper I’ve already posted about. This is the first podcast I’ve ever been involved in, so any feedback you have (apart from telling me that I sound drunk in my first sentence, I’m not sure what that’s all about) will be most welcome!

posted by Graham Lee at 13:59  

Tuesday, July 8, 2008

CocoaHeads Swindon

Just got back from the first meeting of Swindon CocoaHeads, featuring a bunch of people who live nowhere near Swindon, some good beer and the occasional discussion of Cocoa. Special mention to Scott who came all the way from sunny Warsaw to be with us!

Tonight’s event was an informal, “what do we want from Swindon CocoaHeads?” event, but it looks like being successful enough that we’ll be doing it again. The format will be a presentation or directed conversation, followed by general chit-chat about all things Cocoa. In fact, um, I may have volunteered to give the first presentation at the next meeting. The subject is: well, that would be telling, wouldn’t it… ;-). You’ll have to find out by coming along to the Glue Pot in Swindon at 8pm on Monday, August 4th. Look out for further announcements and a mailing list over at Scotty’s place in the forthcoming month!

posted by Graham Lee at 00:47  

Powered by WordPress