Evolution of emacs lisp

I remember having tons of fun playing around with Joy back when I was but a wee little lisp-brained (derogatory) kid. Of course now I am a medium-sized lisp-brained, uh... person, who has no time for such things, but lots for theory.[0]

Here is a theoretical denoscription of Joy, written by Manfred Von Thun himself. The way he describes it makes it sound like one of the most beautiful languages ever invented[1], and it is, really — to the point it made me wonder if lisp really is the most elegant form for a programming language.

It's difference with Forth, the most well-known concatenative language[2], is in quotations (pun not intended). [Quoting] a program doesn't evaluate it immediately, but pushes it onto the stack in the form of a list to be evaluated later. All lists are quotations, technically.

So it is like Lisp! Kind of. The difference is that it's concatenative, so all arguments are tacit and composition of functions is denoted by concatenation. That also means all functions are fixed arity (since every function takes a stack and returns a stack). Compare:

(f (g (h x)))

vs.

x h g f

The lack of formal parameters makes use of higher-order functions... impractical. So there are none. Instead, Joy uses combinators — functions that perform dequotation. Here's the Y combinator in λ-calculus:

Y = λf. (λx. f (x x)) (λx. f (x x))

and here it is in Joy:

y == dup [[y] cons] dip i

(here the i combinator evaluates the quoted expression on top of the stack)

Anyway, the reason I brought this up is because I've stumbled on this lang called Cat, which is basically that, but statically typed, if you're into that sort of thing.


"For any algebra, any relational structure, any programming language it is possible to have alternative sets of primitives and alternative sets of axioms. Which sets are optimal depends on circumstances, and to evolve optimal sets takes time. One only needs to be reminded of the decade of discussions on the elimination of goto and the introduction of a small, orthogonal and complete set of primitives for flow of control in imperative languages."

— Manfred Von Thun

[0] Incidentally, Mathematical Foundations of Joy, another theoretical denoscription of the language, is where I learned what a monad is.

[1] And I almost paraphrased it here, but I really think that if you have any interest in PL design or notation you should check out the linked text, it reads like poetry. If you're in a hurry, the FAQ describes the same thing, except with less theory stuff.

[2] Legend has it Joy wasn't actually inspired by Forth, but rather evolved independently. I'm no expert, but convergent evolution usually screams "Good Idea".

презентация доклада и его версия-лонгрид без типологии и главы о найденном звуке

https://hsedesign.ru/project/0daea155d0fe463d878b767ee8bbd730

На самом деле в этом блоге статья как сделать свой псевдоскоп
https://pseudoscope.blogspot.com/

Это такая штука, чтобы менять изображения между глазами. То есть правый видит то, что должен видеть левый и наоборот. Из-за этого перспектива выворачивается.

https://en.wikipedia.org/wiki/Pseudoscope

на хакернюс в комментах скинули Э Т О
https://alpha.trycarbide.com/
будущему уже десять лет (домен в 2016 году зареган)

https://github.com/larsmagne/bookiez.el
*perplexity API usage*