Show HN: The Y Combinator Codex

The handwritten Y Combinator Codex came to life when I noticed that emacsomancer has created https://gitlab.com/emacsomancer/ycombinator-codex/ [0] - a set of three Lisp functions typeset in a recreation of olde English text.

I have been doing calligraphy as a hobby for more than a decade. Given this fact, I promptly decided that nobody performs historical Lisp typesetting on my watch without consequences, and these consequences happened to become a 42cm x 2.4m calligraphy piece containing the very same Lisp code: the Y combinator along with its two practical applications.

The details about the piece are already on the website; if you have any more questions, then AMA, I guess.

[0] See this link for an ASCII version of the source code of the Y combinator. This code is going to work in any Common Lisp implementation when called like this:

    CL-USER> (mapcar #'fib '(1 2 3 4 5 6 7 8 9))
    (1 1 2 3 5 8 13 21 34)
    
    CL-USER> (mapcar #'fac '(1 2 3 4 5 6 7 8 9))
    (1 2 6 24 120 720 5040 40320 362880)

Beautiful!

If it’s not clear this is the original meaning of Y combinator in computer science. Here is a link I found about it:

https://mvanier.livejournal.com/2897.html