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Anonymous recursive functions in Racket

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88 points azhenley | 3 comments | 04 Sep 25 00:39 UTC | HN request time: 0.204s | source
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userbinator ◴[06 Sep 25 21:07 UTC] No.45152834[source]▶
A relevant article to the domain name of this site.
replies(1): >>45153238 #
drivenextfunc ◴[06 Sep 25 21:56 UTC] No.45153238[source]▶
If you look at the code, you'll be (unpleasantly) surprised, I think. The author does not seem to have known what Y combinator is.
replies(6): >>45153365 #>>45153725 #>>45153889 #>>45153967 #>>45154096 #>>45154105 #
1. skrishnamurthi ◴[07 Sep 25 00:17 UTC] No.45154096[source]▶
If it helps, you will find the Y-combinator described (indeed, derived) in the first edition (https://cs.brown.edu/~sk/Publications/Books/ProgLangs/2007-0...) of the author's programming languages book (https://www.plai.org/). (Page 228, if that helps, though the derivation begins on page 223.)

For added fun, the day he teaches it in class, he wears a t-shirt from Y-combinator the startup accelerator (and explains what its name means).

Now that we've gotten that out of the way, it remains unclear what is surprising or unpleasantly surprising about the code.

replies(2): >>45155354 #>>45155630 #
2. adityaathalye ◴[07 Sep 25 04:16 UTC] No.45155354[source]▶
Shriram invoking Shriram ... (λ.x (x x) λ.x (x x)) forever \m/ :)
3. userbinator ◴[07 Sep 25 05:25 UTC] No.45155630[source]▶
This reminds me of when John Nagle showed up in a thread about his algorithm on here.