Another Haskell and Clojure Post

Posted on February 15, 2017 by Sanchayan Maity
Tags: haskell, clojure

Been a while since I wrote about anything here but it’s time to be regular about this again. And oh no! Another Haskell and Clojure post, just like so many others on the web. Well this will be about my experience.

I don’t remember how I heard about Haskell the first time, but, since then I have tried at least thrice to pick it up. Two times I tried with the book Learn You a Haskell for great good and the other time I tried referring Real World Haskell. Neither of them stuck with me, even though the LYAH book is recommended quite a lot. This last June I came across Haskell Programming from First Principles. After reading the reviews online and checking out a pirated copy, I decided it was definitely worth it. Yes, I had an ebook version of it, but I still bought it on my birthday after spending 4000+ INR on it. I gave it as a present to myself and boy was it worth it, worth every penny.

Let’s digress a bit to talk about Clojure and we will come back to Haskell in a while. I was also trying to learn Clojure for a while now. Having read about “code is data and data is code” in the context of LISP languages, I wanted to try it out. The only dialect worth trying it seemed to me was Clojure. Now while I do not care about Java and find it too verbose, it cannot be denied that the JAVA ecosystem gives one access to a lot of things. And while I might not land a Haskell job in India, I might just land one with Clojure. So seemed practical as well.

I was taking CS 425 Database class in the summer semester and the professor wanted us to do a JDBC assignment with one of RDBMSes. I thought what better oppurtunity than this to try some Clojure. So I wrote an application in Clojure which automates running of TPC-H queries for measuring database performance. I used the JDBC driver for Postgres.

Coming from C which is a weakly typed language Clojure’s dynamic typing did not go well down with me. While it was fun to program in Clojure, but, I would make stupid mistakes and then only find them at run time. This is a problem with all dynamically typed languages. There is the source to sink problem. The origin point of error would be somewhere else and the stack trace or exception would originate somewhere else. This is not at a problem while programming in Haskell. Haskell’s strong typing nature can catch all such errors at compile time. I personally prefer this. Stupid people like me who cannot keep all of the code in the head at any given time, prefer to leverage the type system and compiler for not facing such problems.

Haskell’s code is also much more pleasing to my eyes than Clojure/LISP’s parenthesis style since I find the former easy to parse than the latter. Although LISP style makes sense since it is an abstract tree representation as well of the code, but, still nah!. Though given a choice to not work in Embedded/C and with no Haskell shop around, I would like to work in Clojure.

So I am trying to learn Haskell at the moment from the Haskell book and currently at Foldable chapter. Ten more chapters to go before I can call myself a beginner Haskeller. After that it will be time to learn some Yesod and go through Simon Marlow’s Parallel and Concurrent Programming in Haskell. Also I have now switched from using Jekyll for my blog to using Hakyll. The blog as is currently, is in pretty early stage. I have some things to figure out like taking care of code snippets and highlighting them properly. But using Hakyll will also allow me to play around with Haskell. I do not give a crap about Ruby anyway on which Jekyll is based. Also intend to switch to xmonad from i3, however my xmonad configuration still requires some work before I can make it work just like i3.