The Road to Lisp Survey

Saturday, November 13, 2010 :: Tagged under: pablolife plt engineering. ⏰ 3 minutes.

Hey! Thanks for reading! Just a reminder that I wrote this some years ago, and may have much more complicated feelings about this topic than I did when I wrote it. Happy to elaborate, feel free to reach out to me! 😄

I, Paul Meier, do solemnly offer these responses to the Road to Lisp Survey

When did you first try Lisp (meaning here and throughout the survey "any member of the Lisp family") seriously, and which Lisp family member was it?

I took Lisp seriously after my first exposure to it, in Shriram Krishnamurthi's programming languages course, based on his excellent book, PLAI (download it! it's free!). We mostly used Scheme for the course (the implementation now called Racket), and while I could call the programming from that class my first exposure, I really only explored it during self-study after the course.

In the Preface to his book, Shriram mentioned The Little Schemer as a good introduction to thinking in Scheme. In the Acknowledgments, he said "Please read those magnificent books even if you never read this one" of two books, one of them being Structure and Interpretation of Computer Programs. I picked them both up that Winter, and I was hooked.

What led you to try Lisp?

The answer is really in the next question, but I'll also mention that this was not just my first exposure to Lisp, but functional programming as a whole. While I enjoyed programming to a point, what really interested me in Computer Science was the strong theoretical results we'd achieved: the fact that we could prove undecidability kept me awake for weeks.

So part of my migration to Lisp wasn't just to homoiconic syntax and dynamic type systems: it was also the wonders of functional programming I would find prominently in Scheme.

If you were trying Lisp out of unhappiness with another language, what was that other language and what did you not like about it, or what were you hoping to find different in Lisp?

I took the languages course at the same time I took our excellent graphics course, where we used C++. I found I spent much, much longer debugging the C++ programs, for a much less interesting class of bugs. You'd pull your hair out, looking at memory addresses and pointer values only to find you did your pointer arithmetic wrong (we were investigating a two-dimensional matrix stored as a linear array), or that a state change occurring in an edge case was leaving your program in an inconsistent state. It was frustrating, to say the least.

In Scheme, I was only fixing logical bugs. I spent more time thinking than typing. My programs were shorter and elegant. It's as if, by framing the problem differently, hundreds of edge cases and corner cases simply ceased to exist.

And there's something to that. Removing state means putting a lot more effort up front, but ultimately makes your programs worlds easier to write and maintain after you've invested. Not to mention spending your brain cycles modeling is worlds more fun spending them debugging.

Of course, I didn't know that back then; I moved because I just had the feeling they were doing something right, and I could learn something valuable.

How far have you gotten in your study of Lisp? (I know, that is hard to measure)

This is very hard to say. In many ways, I'm still a novice, since most of my Lisping doesn't take full advantage of macros, Lisp's crown jewel. I'm still much more comfortable in Scheme than CL, Clojure, or Arc; I'd call myself a competent Lisp programmer having written a few small programs and baby scripts, with a toe in advanced and a longing to go expert.

What do you think of Lisp so far?

I think it's still a very advanced, progressive way to approach programming, at least with smaller engineering teams. I'm completely unsurprised it's not used in industry as much; it's a large investment, and languages rely heavily on community. Incidentally, I feel the only real rival to Lisp in caliber would be Haskell, who's unofficial motto is "avoid success at all costs." ^_^

Also, any of you see atomo? It looks pretty hip, if ambitious...

Thanks for the read! Disagreed? Violent agreement!? Feel free to drop me a line at , or leave a comment below! I'd love to hear from you 😄