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0 pointsmikelevins8y ago0 comments

I think this comment is unhelpful. The meaning of "Lisp" is a little bit complicated, but I think it can be explained better than this.

"Lisp" has two meanings: (1) ANSI Common Lisp; and (2) the family of programming languages to which ANSI Common Lisp belongs, and which was called "Lisp" many years before ANSI Common Lisp was conceived; that family includes many other languages with quite a bit of variety, including Scheme, Clojure, INTERLISP, T, kernel, picolisp, *Lisp, (the early versions of) Dylan, and many others.

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Jach8y ago

I appreciate the feedback. Maybe my approach could have left out the claim of Lisp == Common Lisp, though I still am amused (as I mention near the end of my later comment) and slightly bothered that such a diverse set of languages (Python too, it's sometimes called an acceptable Lisp) can get called "Lisps" or "dialects of" or "members of the family" rather than an explicitly vague "Lisp-like".

The main direction I was coming from though was that ~10 years ago I was just like the OP, I had read some of SICP and PG's essays and thought I knew Lisp, but no, I just knew a minimal subset of Scheme. Very pretty (https://www.thejach.com/imgs/lisp_parens.png), learned some neat things, but didn't pursue it in favor of practical workhorses like Python et al. I went with the "learn Lisp for the side effects of learning it but don't ever use it" crowd, but I never learned Lisp. It wasn't until much later that I found out Common Lisp was way more than just an ugly syntax change on Scheme that required #' in front of function names. So the features I listed in my comment are really a subset (but a strong one) of the features that would have convinced me ~10 years ago to take a much closer look into actually using Lisp and recognizing I learned something very different.

mikelevinsOP8y ago

I get it; you thought Scheme was Lisp and Lisp was Scheme, and want to prevent others from falling for the same misunderstanding. That's a laudable goal.

Lisp is an old family of languages, though. It's been around a long time, and it's explored a broad range of language ideas and a lot of nooks and crannies. There are a lot of Lisps that are pretty different from each other. There's a pretty good list at Wikipedia (https://en.wikipedia.org/wiki/List_of_Lisp-family_programmin...), but it still omits some interesting variants (for example, *Lisp, Kernel, Lispkit Lisp, Connection Machine Lisp, and others). There are greater differences between, for example, Common Lisp and kernel than between Common Lisp and Scheme, but all of them are still recognizably Lisp.

So you're right: you don't want to be fooled into thinking that Scheme is all there is to Lisp. But Common Lisp also isn't all there is to Lisp. Scheme plus Common Lisp plus Clojure isn't all there is to Lisp, either. It's a big space, and there's room for it to grow bigger still without losing its essential Lispiness.

"APL is like a beautiful diamond – flawless, beautifully symmetrical. But you can't add anything to it. If you try to glue on another diamond, you don't get a bigger diamond. Lisp is like a ball of mud. Add more and it's still a ball of mud – it still looks like Lisp."

-- attributed to MIT Professor Joel Moses