Andrew Ash

Classes have finished for the year, and I finally have some time to get real work done! One of the whole host of things I got involved with this semester was working on designing a new programming language with my friend Alex Marquez.

One of the major hurdles for me is that a new type system is core to the language, and that type system uses all sorts of techniques that I’m unfamiliar with. Type inference, pure functional style, reification, currying, kinds (type of types) and many other things I now vaguely understand with from talking about the language with Alex, but there’s certainly a long way to go.

So I decided to rectify that by giving a shot at Haskell, that crazy, purely functional language with monads and all sorts of interesting things. I’m working through a collection of resources now, and thought I’d collect them here for others to start from.

• The first is Real World Haskell (RWH), the O’Reilly book by Bryan O’Sullivan, John Goerzen, and Don Stewart.
• Next is Learn You A Haskell (LYAH), the quirky tutorial by Slovenian Miran Lipovača.
• I also found the Gentle Introduction to Haskell (GIH), by Paul Hudak, John Peterson, and Joseph Fasel to be useful as well.
• And for a great search engine of Haskell types and documentation, check out Hoogle.

Of the three tutorials, RWH is the most gentle. It also features a wonderfully innovative comment system, where user comments can be made on a paragraph by paragraph basis. Several times I found that a comment had a particularly useful addition or alternate explanation, which greatly added to the straight text. Reading RWH+Comments feels akin to being at a conference while following the backroom chatter on Twitter during a presentation. You’re given both the presentation and the critique, interwoven in time.

But at times, RWH felt a bit too slow at getting to the interesting stuff. I wandered around a bit and found myself at LYAH, which is the site I started learning Haskell from several months ago. With quirky drawings and a good pace, I switched over to using LYAH as my primary Haskell tutorial.

And by browsing around online (imagine…) I came across GIH, the most academic of the three. GIH does an excellent job of formally defining functions and concepts as you move forward, but it’s quite heavy. I found myself glancing at other resources to actually understand what was going on, and in several cases I only understood a piece of code because I’d learned something from another tutorial. I’d say that GIH is better for a later tutorial once you get the big picture of Haskell and are looking for more details. GIH goes into more depth on language constructs and has extensive links to the official Haskell definition and the code implementing the Prelude (standard library).

And a great resource shared with me by friend David Hollis is the search engine Hoogle. I’ve ended up using Hoogle mostly as a reminder of what functions do, not just what their type signature is. And searching by a type signature is something I’ve never seen before. Very cool!

Best of luck in learning Haskell!

News on the research front! Besides pursuing an Amazon AWS research grant, I was selected to be featured in the GT UROP newsletter for my work on the Music Technology research as an undergraduate. The newsletter will be ready to go within a week or so, and I’ll be sure to look out for copies around campus and online.

In the meantime, I have typeset the profile in LaTeX (a favorite to work with, though quite the pain sometimes). Here is the Undergraduate Researcher Profile.

I actually returned from India a bit over two weeks ago, but the standard school fair has been keeping me quite busy. Apart from the research symposium mentioned below (slides coming soon?), I also had to: grade HW, do CS2200 HW, Databases project, 8-10pg PUBP paper, open the TA application, 2200 Project, Research demonstration, Research presentation, Prob/Stat HW, and a 2200 Test. And I was supposed to be playing piano for church and competing in a debate tournament over that weekend, but those just weren’t able to happen…

The India trip was a one-week Friday evening to Sunday morning father-son trip. My dad and I left Atlanta for our 8,500 mile, 17 hour direct flight Atlanta-Mumbai. After sleeping nicely, we arrived at Mumbai’s international airport, met our local contact Pradeep, and made it to the hotel via taxi. Since it was only midnight local time (9:30 in the morning on our bodies!) we went out for some “breakfast”. We spent the next couple days wandering around the back roads of Mumbai, hitting up the highlights of Haji Ali, Sassoon Docks, Gateway to India Arch, Elephanta Island, Mani Bhavan (Gandhi’s house), Cafe Leopold, the Taj Mahal Hotel, and all sorts of intriguing back roads. We have this tendency of tryin to avoid doing just the “tourist thing” when visiting other countries, being ferried around by vehicle from site to site without getting a true experience for the flavor of a country’s local culture.

After Mumbai we took a domestic flight down to Coimbature and taxi’d up to Ooty, where we were able to meet with a couple from our church working on Freedom Firm, an organization working for “rescue, restoration, and justice for victims of sex trafficking”. Really powerful work there. Also while in Ooty we woke up early to track elephants and tigers in a nature preserve, hiked the 3hr Cooley trail (and ran away from a lone male elephant), and visited the tea museum and a local tea factory. This is also where Dad got sick and we lost a morning due to illness. Though it slowed us down, it was a nice break from just experiencing and offered the chance for reflection. How much does experience matter if you can’t take those experiences and forge them into coherency for actually impacting your life?

Leaving Ooty via taxi, we made our way to Mysore to see the palace there, but had to miss it because we’d lost so much time that morning. We ended up barely making it to Bangalore in time to make the overnight train up to Hyderabad. What a fantastic experience! In Hyderabad we stayed at Pradeep’s parents’ house, which had a welcome sense of familiarity even though we’d never been to the place. Although much of our siteseeing in Bangalore didn’t work out, we were able to meet up with some great guys at India Missions Association, where Pradeep’s parents work.

There’s certainly way too much for me to able to fit all of my experiences in today, so maybe I’ll have more posts in the future on this wonderful opportunity to visit India I had.

You would think that in the world we live today, getting ahold of sheet music for some of your favorite songs online wouldn’t be that big of a deal. I mean, just poke your nose into enough dark corners of the internet and eventually what you’re looking for reveal itself. Right? There seem to be plenty of people getting along just fine using that approach for music, movies, TV shows, software, and even e-books now. But you would be surprised how difficult it is to find freely available sheet music, let alone the legal kind.

So what’s a music aficionado supposed to do? Well, I happened to stumble upon a site today that does sheet music right, worshipmusic.com. Sure, it’s a highly specialized target audience, but read this: I was able to buy a digital lead sheet for a song I’ll be playing in a few days for just $2.50. Yeah, two dollars and fifty cents. A nice and simple process too. The standard shopping cart, checkout fare, but then I instantly received a download link via email for the pdf. Not any of those crazy proprietary plugins that tend to cause Firefox crashes, but nice simple pdfs. Exactly what everybody wants. I had a great experience and worshipmusic.com, and would have bought several more songs if they would have had them available for digital download.

Maybe I want everything my way, but it still wasn’t good enough. If I can get a song for $0.99 on iTunes, why should it cost $2.50 for the sheet music? And especially since I’m just downloading a file. You can’t even plead printing, shipping, and distribution costs on that one, buddy. The two and a half bucks was a low enough price point for me on this one-time purchase, but it’d probably need to be closer to the buck-a-pop range that iTunes has gotten. The selection is also extremely limited. Out of six songs I was looking for, they only had one. Browsing was a bit difficult as well. With long lists of items and not much effort put into usability, particularly categorizing the catalog, it took a while to figure out that they even had that song.

So what would the perfect sheet music store look like for me? Probably a lot like Amazon.com‘s mp3 downloads, but with pdf files instead of mp3. It’s a clean store, easy to find things. The download process is simple, and gives you exactly what you wanted: that file quickly, easily, and legally. If old media is to not get run over by turning public opinion regarding file sharing, they’ve got to fight with products, not lawsuits. And this sort of product is exactly what I’m looking for.