afongen

My presentations at the MnSCU IT conference a couple weeks ago were mixed.

The Ruby on Rails talk did not go well. I decided to start with a demo to give some flavor of what Rails development is like and how very little code it takes to get up and running. I had trouble with the demo so ended up behind schedule and didn’t get to talk enough about what I really think is important. I like Rails well enough, but about a month ago I realized that I wasn’t all that interested in talking about it. To my mind, it’s a bit over the top to claim that it’s the future of web development, although its release did mark the emergence of energetic activity in the web app framework space that embraces DRY and convention over configuration. Less code. Rails is interesting and downright fun, but so are the similar frameworks that came out at about the same time: Django, TurboGears, Symfony, CakePHP… I wanted to focus not on Rails but on the ideas it represents, but I didn’t leave enough time. I had hoped, too, to talk about share nothing architectures and spend a little more time plugging dynamic languages. But it’s over, and that’s just fine. I don’t think I’ll be doing many live demos in the near future, and I might stay away from Big Idea talks — or at least structure them differently.

The Ajax presentation, which I did in collaboration with Dave Kruse, webmaster at South Central Technical College, was much better. Planning for it, Dave and I struggled with how to address the fact that the audience would have all sorts of skill levels ranging from knowing nothing about Ajax or even JavaScript, to understanding XMLHttpRequest at a really deep level. We opted to avoid lots of technical explanation and code examples. Instead of focusing on the technical, we talked more about the ways in which Ajax is changing how people experience web apps, what they expect from them, and how to ensure that using Ajax improves the user experience. Because that’s what it’s all about.

Would like to have had more handouts, but time got the better of me and flu got the better of Dave, so that didn’t happen.

During breakfast before the session, I threw together some code examples using Prototype, which I did end up showing since we had some time left. Also at breakfast, Dave worked on some Flash animation illustrating the difference between traditional web application interaction and Ajax-style asynchronous requests. He dismissed them as hopelessly cheesy, but despite the lack of polish I think they do a better job of visually representing Ajax at work than anything else I’ve seen. I’ll try to get Dave’s permission to post them here.

MP3s will be available at some point.

The best part of the conference was the conversation, connecting with my colleagues on the campuses. Face-to-face is a Good Thing. Getting to work with the amazingly talented people at our colleges and universities is one of my favorite aspects of my job.

The next best thing was the introduction of Al Essa, who started working with us a few weeks back as Associate Vice Chancellor / Deputy CIO, and from what I saw at the conference people are impressed. As they should be. I’m downright giddy about Al joining us. This Educause interview with him should make it clear why: he’s thoughtful, articulate, and apparently values many of the same things I do: open source, Web 2.0 (yeah, yeah), dynamic languages… Even in his first weeks here, sounding out the territory, I get the sense that he has Ideas.

And he blogs. Check. I’m pretty sure I ended up at his blog via Stephen O’Grady, which is another good sign.

I’ve been way too with conference preparation and family life to write much, but I’ve had a lot of things rumbling around in my head that are dying to get out. I saw this cartoon by Hugh Macleod today and thought it about sums up everything I’ve been thinking:

Then I decided that this is a bit closer to the mark:

More soon.

A few events I won’t be able to attend but that might catch your geeky interest.

First, tomorrow at the Minneapolis/Saint Paul Java SIG, Tom Enebo and Charles Nutter, leads for the JRuby project, will be talking about JRuby. Dynamic languages that run on the JVM are becoming more and more interesting to me, so I wish I could make it to this one, especially since I missed their JRuby presentation for the local Ruby users group. (Side note: Tim Bray recently managed to get Sun to donate a couple Sun Ultra 20s to the project, which will help nicely.)

Next week on April 18, another local Object Technology User Group event: Ryan Asleson and Nathaniel T. Schutta will be talking about Ajax. Asleson and Schutta are the authors of Foundations of Ajax, which has come recommended to me. I can’t make it because I’ll be up at our MnSCU IT conference, settling in quaffing a few and preparing my own Ajax talk.

Also on the 18th, the Twin Cities OWASP Chapter is meeting. This time they’re in Roseville, in the offices of Integral Business Solutions. I’m glad to see them a bit closer to me instead of out in the western suburbs. Unfortunately, I still can’t go since I’ll be in Brainerd. Rats! But maybe you can. I recommend it; the OWASP chapter is really taking shape.

Listened to the third episode of RedMonk Radio on my way in today. My favorite bit:

Coté: There’s the evolution of, y’know, way back when the military radar system drove technology, right, and then there was NASA, and then it went into private enterprise, and now it’s kind of the consumer space that seems to drive everything.

James: Oh, Coté, you’re my man, I’m so glad you’re saying that. Let’s create games platforms to drive technology instead of war to drive technology. I am all about that. Consumer-driven innovation is the better kind. Let’s stop funding all the military stuff and fund fun that will drive technology.

Right on.

Rubyists talk about methods calls as sending message to objects, a notion that I understand is inherited from Smalltalk. It always seemed a little strange, but I could accept it as an odd quirk (“Bah! I understand method calls!”) and move on to writing code. This is unusual behavior for me, since normally I try to understand a language on its own terms. Now, though, I think I finally grok all this talk of messages, thanks to A Little Ruby, A Lot of Objects, an incomplete book in the style of The Little Schemer. And as it turns out, terminology matters.

class Dog
  def speak
    "Woof!"
  end
end

fido = Dog.new

Calling the speak method on fido (fido.speak) is really sending a message to the fido object. When fido receives the “speak” message, it knows to invoke the Dog class’s speak method. It answers, or returns, with the String “Woof!”

Yeah, that doesn’t seem too special, does it?

But here’s the thing. In Ruby, everything’s an object. 2 is an object of type Integer. 2 + 5 in Ruby is really saying, “Send the message “+” to the object 2, along with the parameter 5.” That is, 2 + 5 is convenient shorthand, syntactic sugar for 2.send("+",5) (which is, by the way, valid Ruby). 2 receives the message and invokes its + method, passing 5 as a parameter. It responds with 7.

Okay, this is still not seeming very special. Doesn’t this just muck up the discussion? Sure, it’s neat that 2 is an object, but what do you gain from all this talk of sending messages?

I’ll tell you where it finally clicked for me: polymorphism. I’m not sure why, but for some reason polymorphism is often a tricky concept for beginning programmers. Couched in terms of sending messages to objects, it’s crystal clear (at least to me :). You can send the same message to different objects, each of which will invoke the appropriate method of its class.

class Cat
  def speak
    "Meow!"
  end
end

garfield = Cat.new

With both fido.speak and garfield.speak, we’re sending the message “speak” to the object. fido receives the message and invokes its speak method, and garfield invokes its own speak.

+ does different things for Strings and Integers. This is commonly called operator overloading.

2 + 5 == 7
"Abe " + "Lincoln" == "Abe Lincoln"

The message is the same: “+” — but the methods are different. Ah ha!

And now I finally understand duck typing in relation to polymorphism. It should have been obvious earlier, but I never thought of it in that way (probably because I figured that polymorphism wasn’t that tricky, so I didn’t think about it). Dave Thomas’s explanation of duck typing is fairly clear. In Ruby, types are defined by what objects can do rather than their class.

When I write

  fred

in Ruby, I don't care whether fred is a String, a File, or an Array

What matters instead is whether fred can respond to the message “A Little Ruby, A Lot of Objects, let me make it clear now: it is a fine read, highly recommended. And now I want to go read The Little Schemer.

Kiara’s getting her Master of Fine Arts in Creative Writing from Hamline this spring, and will be reading from her theses this Friday. She blogs about that over at Wordspinning.

Yes, theses. Maybe it’s just considered one thesis, but she’s done thesis-length works in both poetry and prose. That’s Kiara for you: why do anything half-assed when you can do twice the amount of top-notch work?

It sounds like she’ll be reading “Mary’s Baby,” which is a fine, fine short story embedded in her novel. I’m excited to see how she reads that, as the narrative voices in the story are so strong and so distinct.

The JavaScript shell is nice, but if you’re using OS X there’s a better option. On a tip from Todd Ditchendorf, I’m now running both a JavaScript and a Ruby interpreter in Dashboard, just a keystroke away.

It’s easy. Todd gives directions for installing WidgetTerm, which is key to the whole thing. Then drop a jar from the Rhino project in your Java classpath, set an alias to a JavaScript shell, fire up a WidgetTerm instance, and you’re done. It sounds more complicated than it is.

I need to pay more attention to Rhino. It caught my attention when I read this discussion of choosing a Java scripting language and saw how Rhino stacked up against JRuby, Groovy, Jython, and others. Here’s an obvious application.

No Fluff Just Stuff is in town this weekend and I’m missing it. Sigh. I have to make a more concerted effort to attend this sort of event.

My RSS feed is on Feedburner now, so I am redirecting requests for the RSS there. If you use an aggregator, it should follow the redirect, but you might want to update to the new URL anyway.

Why Feedburner? Two reasons to start:

1. It integrates my del.icio.us links into the feed, which is something I’ve meant to spend ten minutes doing myself but never quite got around to.
2. It creates a pretty version with a style sheet. Something else I’ve meant to spend ten minutes doing but never quite got around to. Story o’ my life.

It will be nice to see some stats on the feed use, too, something I occasionally generate with a series of Perl scripts but don’t follow closely.

On the latest Pro::PHP Podcast, Marcus Whitney interviewed Microsoft’s Brian Goldfarb and Joe Stagner about PHP on Windows.

PHP developers may have already heard this interview (if not, why not? It’s a good podcast!). I wanted to be sure to mention it here because just as I think it’s useful and important for PHP programmers to separate the language from the LAMP platform and get away from knee-jerk reactions against anything having to do with “M$”, I believe that .NET developers should hear discussion from within Microsoft of non-Microsoft languages on their platform and how that might be a Good Thing. Good stuff.

I haven’t talked or written much about it, but I like a lot of what I see in .NET. Microsoft has done a far, far better job than Sun (or Oracle, or IBM…) at marketing to developers. I’m still not about to take much time to play around with .NET, since I don’t have a Windows box at home and have better things to do with my time at work, but it is compelling. I’ll probably watch some of the webcasts at learn2asp.net, and who knows? Maybe I’ll get Mono up and running on my Mac, although I think it’s too early for .NET 2.0 on Mono at this point, right?

Of course, first comes more Ruby, more PHP 5, then Smalltalk, Lisp, Haskell, Erlang… oh, and raising two kids. Do you see my problem? :)

Go listen to the interview.