It really doesn't. k's ancestors were taught to high school students and admin in incredibly short spans of time. Here's an anecdote from Kenneth Iverson about a man who learned APL in two weeks, completely alone, and the results after he taught his students it:
My daughter Janet attended Swarthmore High School, and recommended Rudy Amann (head of the math department) as an excellent teacher. I therefore approached him with a proposal that we put an APL terminal in his school as a tool for teaching mathematics, suggesting that he first spend the summer with the APL group to assess the matter.
Rudy responded that he could spend only two weeks, which he did. I gave him an office with a terminal (and the Calculus text in APL that I had written after our earlier experiment with high school teachers), and invited him to come to me or anyone in the group with questions. Since he never stirred from his office, I despaired, but at the end of the two weeks he announced that he wished to go ahead with the project.
Rudy was pleased with the results, and told me of canvassing those of his students who went on to college, finding that they were pleased with the preparation he had given them. One thing he had done was to use some of the final two “review” weeks to show them the translation from things like +/ to the sigma notation they would encounter in college.
Here's another where they taught it to high school teachers, with a direct explanation as to how students responded:
I believed that APL could be used in teaching, and Adin said that to test the point we must take a text used in the State school system, and try to teach the material in it. He further proposed that we invite active high school teachers.
We hired six for the summer, with the plan that two (nuns from a local school, who could provide a classroom in which we supplied a computer [typewriter] terminal) would do the teaching, while the other four (with a two-week head start) would write material.
To our surprise, the two teachers worked at the blackboard in their accustomed manner, except that they used a mixture of APL and conventional notation. Only when they and the class had worked out a program for some matter in the text would they call on some (eager) volunteer to use the terminal. The printed result was then examined; if it did not give the expected result, they returned to the blackboard to refine it.
There were also surprises in the writing. Although the great utility of matrices was recognized (as in a 3-by-2 to represent a triangle), there was a great reluctance to use them because the concept was considered to be too difficult.
Linda Alvord said to introduce the matrix as an outer product — an idea that the rest of us thought outrageous, until Linda pointed out that the kids already knew the idea from familiar addition and multiplication tables.
Finally, it was this interest in teaching that led us to recruit Paul Berry, after seeing his Pretending to Have (or to Be) a Computer as a Strategy in Teaching when it appeared in Harvard Educational Review, 34 (1964), pp. 383-401.
So then, why is K less popular than pretty much any other language? Because people are stupid? Uninformed? There's a lack of PR-minded people working with K? What exactly is your theory? It's funny that a language this flawless is slightly less popular than S or D or pretty much any other one-letter language. There must be something that makes it unappealing for the masses of programmers - what is it?
Javascript must've done _something_ right, no? Yes I know it's bad from "language design" perspective, but we all know what it did right: it was embedded out-of-the-box on a very popular platform (the browser). So, there is an explanation.
Do note that I didn't claim "popularity == quality". I'm not even claiming K is bad!!! Just that it's strange for something so clearly superior to everything else to be such a niche language. Surely it must have downsides...
Why is it strange? Think of languages like Lisp, Smalltalk, Haskell. You may not find them on top of TIOBE, but their innovations do trickle down to mainstream, indicating that the designers of mainstream languages find them worthwhile.
Array languages are very much poised to do the same, if they did not already: numpy is essentially a poor (and verbose) man's array language embedded in python. Or consider Matlab.
> "A LISP programmer knows the value of everything and the cost of nothing."
Here, a very old quote that tells you directly what is wrong with FP - the performance on old hardware sucked. For a very long while compilers/interpreters were not good enough.
The cost/benefit equation changed in recent years, and sure enough, FP ideas are becoming mainstream.
Again, I'm not saying that array languages don't have fundamentally great ideas. I'm saying that articles like this one do them no favor - they're just smug rants. Show the world you understand the downsides, and you get a better chance of promoting the upsides.
k costs $20,000 per-core (less accurate now than it used to be but I'm pretty sure it's still true for commercial uses). It has a billion-dollar company based entirely around it (Kx/FD) and a smaller multimillion one, so it worked out well, I guess.
J is free, but J has never had an advertising budget, and was only freed recently.
APL's current leading implementation is really bad in comparison to how nice the language used to be, and just as proprietary. It was also significantly nicer to input back when APL keyboards existed and typeballs did as well.
Very few people strike gold and then have the willingness to not sell it at market-rate. Unfortunately, most people implementing APL are very aware of the rate. And it's high.
A language doesn't cost... the environment might. Why did nobody pick up on the ideas? C# is not inspired by K, Go is not, Swift is not, Rust is not, Clojure is not... I mean, take any big or small company that decided "we need a new programming language" - I'm not aware of many taking inspiration from K.
I get it, there are people who love K, and are productive in it. And I'm not even claiming the ideas of K are inherently bad! But you know, when the rest of the world "doesn't get it", _maybe_ the reason is not that the rest of the world is dumb? Articles like this one do K no favor, IMO.. they might "feel good" but they IMO don't prove that K programmers are superior beings who reached enlightenment - they prove the exact opposite, lack of understanding the rest of the world. It's fine to say "I'm quirky and it's fine, this makes me special". It's wrong to say "The rest of the world is quirky, they don't share my niche preferences".
Go was, by the author's own admission, a language for the lowest common denominator (the computer science undergrad). In many ways, the computer science undergrad is less competent than someone with no formal backing at all: it takes less time to teach a new skillset to a blank slate than repair the damage done to undergrads. Rob Pike's hobby is working on an APL interpreter.
C# was Microsoft's answer to Java after getting sued for cloning Java.
Rust is by C++ devs, for C++ devs.
Swift was Apple's successor to Objective-C.
Clojure is another language doing the "Lisp but with a bootstrapped ecosystem" thing, by a guy who had been active in the Java, .net, and CL communities.
All languages build on something, and when the mainstay languages are all ripping off ALGOL-60, ALGOL-60 clone after ALGOL-60 clone is what you will get.
Programming languages are just now starting to become influenced by Prolog despite the benefits of Prolog for certain tasks being apparent; the entire result of the field right now can roughly be traced entirely to UT Austin.
The point of the article was not to claim anything about the superiority of k programmers, it was to point out that the rest of the world was extremely close-minded to anything with different syntax in a comical way, along with demonstrating that a common criticism (of which there are many, 99% of which unfounded, as you can see by checking any thread on Hacker News that even briefly touches upon k or APL) was hypocritical, which I think it did a great job at.
It was a reference to the Kübler-Ross model, which does seem to apply to people who find APL/J/K at some point.
> But you know, when the rest of the world "doesn't get it", _maybe_ the reason is not that the rest of the world is dumb?
Look at the kind of replies you get on every hn thread on APL/J/K - the majority of the negative comments around readability are emotional/gut level responses.
People aren’t trying to understand K examples for a couple of hours and failing... they are making snap judgements based on their experiences in other languages.
My daughter Janet attended Swarthmore High School, and recommended Rudy Amann (head of the math department) as an excellent teacher. I therefore approached him with a proposal that we put an APL terminal in his school as a tool for teaching mathematics, suggesting that he first spend the summer with the APL group to assess the matter.
Rudy responded that he could spend only two weeks, which he did. I gave him an office with a terminal (and the Calculus text in APL that I had written after our earlier experiment with high school teachers), and invited him to come to me or anyone in the group with questions. Since he never stirred from his office, I despaired, but at the end of the two weeks he announced that he wished to go ahead with the project.
Rudy was pleased with the results, and told me of canvassing those of his students who went on to college, finding that they were pleased with the preparation he had given them. One thing he had done was to use some of the final two “review” weeks to show them the translation from things like +/ to the sigma notation they would encounter in college.
Here's another where they taught it to high school teachers, with a direct explanation as to how students responded:
I believed that APL could be used in teaching, and Adin said that to test the point we must take a text used in the State school system, and try to teach the material in it. He further proposed that we invite active high school teachers.
We hired six for the summer, with the plan that two (nuns from a local school, who could provide a classroom in which we supplied a computer [typewriter] terminal) would do the teaching, while the other four (with a two-week head start) would write material.
To our surprise, the two teachers worked at the blackboard in their accustomed manner, except that they used a mixture of APL and conventional notation. Only when they and the class had worked out a program for some matter in the text would they call on some (eager) volunteer to use the terminal. The printed result was then examined; if it did not give the expected result, they returned to the blackboard to refine it.
There were also surprises in the writing. Although the great utility of matrices was recognized (as in a 3-by-2 to represent a triangle), there was a great reluctance to use them because the concept was considered to be too difficult.
Linda Alvord said to introduce the matrix as an outer product — an idea that the rest of us thought outrageous, until Linda pointed out that the kids already knew the idea from familiar addition and multiplication tables.
Finally, it was this interest in teaching that led us to recruit Paul Berry, after seeing his Pretending to Have (or to Be) a Computer as a Strategy in Teaching when it appeared in Harvard Educational Review, 34 (1964), pp. 383-401.
(From KEI's delightful but sadly unfinished autobiography: https://www.jsoftware.com/papers/autobio.htm)