The code-as-data, self-similar aspect of Lisp, which is at the core of Lisp's macro features, hasn't reached the same popularity.

I would say that Lisp has both won and lost.

BASIC was mature as a teaching language that you could run on a microcomputer by the early-1970s (see https://en.wikipedia.org/wiki/RSTS/E) and it came to dominate the market because there were implementations like Tiny BASIC and Microsoft BASIC that would run in machines with 4K of RAM.

There was endless handwringing at the time that we were exposing beginners to a language that would teach them terrible habits but the alternatives weren't great: it was a struggle to fit a PASCAL (or FORTRAN or COBOL or ...) compiler into a 64k address space (often using virtual machine techniques like UCSD Pascal which led to terrible performance) FORTH was a reasonable alternative but never got appeal beyond enthusiasts.

There was a lot of hope among pedagogues that we'd switch to LOGO which was more LISP-like in many ways and you could buy LOGO interpreters for everything from the TI-99/4A and TRS-80 Color Computer to the Apple ][. There was also µLISP which was available on some architectures but again wasn't that popular. For serious coding, assembly language was popular.

In the larger computer space there were a lot of languages like APL and SNOBOL early on that were dynamic too.

It had its limitations, but it damn well worked and you could have total control of the machine if you needed it.

(also the Acorn Archimedes manual was about 40% "how to use the gui" and 60% a complete introduction and reference for BBC BASIC, which definitely helped; I had to buy a book to get an explanation of the ASM side of things but, I mean, fair enough)

Then again the second time I fell in love with a programming language was perl5 so I am perhaps an outlier here.

It's clear to me that S-expr are not popular.

Other languages and environments have captured much of what Lisp has offered forever, but not S-expr, and, less so, not macros.

Any argument one has against Lisp is answered by modern implementations. But, specifically, by Clojure. Modern, fast, "works with everything", "lots of libraries", the JVM "lifts all boats", including Clojure.

But despite all that, it's still S-expr based, and its still a niche "geek" language. A popular one, for its space, but niche. It's not mainstream.

Folks have been pivoting away from S-expr all the way back to Dylan.

I'm a Lisp guy, I like Lisp, and by Lisp I mean Common Lisp. But I like CLOS more than macros, specifically mulithmethod dispatch. I'd rather have CLOS in a language than macros.

I don't hate S-expr, but I think their value diminishes rather quickly if you don't have macros. Most languages have structured static data now, which is another plus of S-expr.

I don't use many macros in my Lisp code. Mostly convenience methods (like (with-<some-scope> scope <body>)), things like that). Real obvious boiler plate stuff. Everyone else would just wrap a lambda, but that's not so much the Common Lisp way.

In my Not Lisp work, I don't really miss macros.

Anyway, S-expr hinder adoption. It's had all the time in the world to "break through", and it hasn't. "Wisdom of the crowds" says nay.

The appearance of new languages like this has not stopped.

There aren't "many" popular languages; only a fairly small number. The vast majority of languages are destined for unpopularity, regardless of what they copy from where.

When we go back to the original idea of LISP, we have the following things:

idea -> what follows from those

1) programming with Symbolic Expressions -> support the implementation/implementation of languages

2) "programming with Symbolic Expressions" applied to itself -> Lisp in itself, code as data, macros, self-hosting compiler, Lisp interpreter

3) linked lists and symbols as data structures for Symbolic Expressions

4) a programming system to build algorithms and programs based on the ideas of above -> symbols repository, late binding, recursive functions, symbols with properties, garbage collection, Lisp interpreter using s-expressions, Lisp compiler, reader, printer, read-eval-print-loop, a resident development environment, managed memory, saving/loading heap dumps, dynamic data structures,...

LISP means "List Processor" (not "List Processing"). Which indicates that this is at its core, not a library or an add on.

There aren't that many other languages which are based on these ideas.

We can define three levels of "feature adoption":

* enables a feature (the language provides mechanisms to provide a feature)

* supports a feature (the language actually includes those features, but use is optional)

* requires a feature (the language requires the use of that feature, its not optional for the developer)

If we use a programming system, which requires the four core ideas above (and many of the features that follow from those) and is based on them, it is still very (!) different to what most people use.

Example:

Smalltalk development was started more than a decade after LISP. It adopted a huge amount of features from Lisp: managed memory, resident development environment, garbage collection, late binding, interactive use, runtime evaluation, dumping&loading heaps, etc. etc. For a decade Xerox PARC developed a Smalltalk system and a Lisp system side-by side: Smalltalk 80 systems and Interlisp-D systems were the results.

Still: Smalltalk 80 did not use the first three core ideas from above and replaced them with another core idea: objects+classes communicating via message passing.

Thus mass feature adoption alone does not make Smalltalk fundamentally to be a LISP. Nor does feature adoption make a language popular.

So we can ask use, will those core ideas of Lisp make it very popular? Seems like it did not. Still many of the useful features which were following from it could be replicated/adopted/morphed into other languages.

The original article was probably taking a view that a language&programming system which enables domain specific embedded languages would be "better" than the diverse stack of tools and languages in the automotive domain. Lisp is such a tool for embedded languages (embedded into a hosting language, not in the sense of languages for embedded systems), but that does not make it the best for that domain, which has a lot more requirements than language embedding (like reliability, robustness, etc. ...). In Germany A-SPICE gives a lot of hints what a development process needs to do, to deliver reliable software for the automotive domain. I don't think Lisp would fit well into such a development process.

It's not that the homoiconicity of S-expressions makes it easier to write macros. Plenty of infix expression languages have macros that let you manipulate ASTs. We're programmers; mapping from lexical syntax to an AST is not hard for us.

What makes s-expressions so great in macro-heavy code is that the simplicity and regularity of the syntax lets you create DSLs without having to fuss with defining your own syntax extensions or figuring out how to integrate it into the "parent" language in a way that isn't completely terrible.

Racket demonstrates this rather nicely. They've got a fantastic system for creating macros that let you define your own syntax. It really does work well. But I'd generally rather not use it if I don't have to, because if I do then the job instantly gets 10x bigger because now I have to write a parser plus all the extensions to make sure it won't break syntax highlighting, ensure parse errors are indicated nicely in the editor, etc. And also all that work will be tightly coupled to DrRacket; people who prefer a different editor will not get a good editing experience if they use my macro.

I can avoid all of that headache if I just let it be s-expressions from top to bottom.

Whaaaaat???

I read the K&R book (rev 1) all the way through. The only thing I found confusing (without a compiler to experiment wiht) was argc and argv. Other than that, I found it very clear.

What, specifically, are you referring to?

I've often thought Sun and Solaris also won, since so much of Linux is open source reimaginings of what Solaris had in the mid-late 90s, essentially a few year head start on Linux (which i used in the early 90s and still do, but along with Solaris back then, and NeXTstep).

(this was not a complaint, we were both veterans of the "How Many UNICES?!?!?!" era)

Aww you can't just leave us hanging like this. What's the paradox?

What do you mean?