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by vnorilo 921 days ago
TFA is about philosophy, but the computer science concept is also interesting - composition of recursive functions.

https://en.m.wikipedia.org/wiki/Hylomorphism_(computer_scien...

4 comments

The article that explores these recursion schemes is: Functional Programming with Bananas, Lenses, Envelopes and Barbed Wire

https://maartenfokkinga.github.io/utwente/mmf91m.pdf

There is a review of this article, although it is quite readable in and of itself:

https://reasonablypolymorphic.com/blog/recursion-schemes/ind...

Thanks, this was my initial thought as well! Generally: https://ncatlab.org/nlab/show/recursion+scheme

(I'm actually kind of surprised ncatlab has this article!)

Hah. My first read was that this way of looking at the world sounds object-oriented (an instance of a class being state encapsulated with function). Just goes to show how quickly any philosophy can lead to a schism ;)
Yes: the class is the form; the data values are the matter. A superclass is a genus and a subclass is a species. I have long suspected that the creators of Simula had a grounding in Aristotelian metaphysics.
It is true that particular interpretations of Aristotle have led to the construction of our modern world, and that the text is constantly in tension with the material it is grounded in, and vica versa--like Heidegger's notion of World and Earth in "The Origin of the Work of Art" (a great introduction to Heidegger, if you're curious).
My intuition is that bits are pure matter. Data Values are bits with an interpretation, already more than pure matter.
Also: 21 Hylomorphisms and nexuses from Pearls of Functional Algorithm Design: https://dai.fmph.uniba.sk/courses/FPRO/bird_pearls.pdf