[HN Gopher] Lambda Calculus - Animated Beta Reduction of Lambda ...
___________________________________________________________________
Lambda Calculus - Animated Beta Reduction of Lambda Diagrams
Author : perryprog
Score : 135 points
Date : 2025-11-24 05:17 UTC (17 hours ago)
(HTM) web link (cruzgodar.com)
(TXT) w3m dump (cruzgodar.com)
| __grob wrote:
| This is sick, loved the 2swap video on this. Happy to see more
| content visualizing lambda calculus and Tromp lambda diagrams.
| ggm wrote:
| The number of reduction steps in division.
| Vosporos wrote:
| Cheers, I love it!
| tromp wrote:
| You can enter (ln.n(lc.la.lb.cb(lf.lx.f(afx)))Fn0)7 to compute
| the function Col' from [1] to 7, resulting in (3*7+1)/2 = 11.
| Unfortunately, this visualization is much less insightful than
| showing the 7 successive succ&swap operations:
| 7 0 0 8 8 1 1 9 9 2
| 2 10 10 3 3 11
|
| [1] https://news.ycombinator.com/item?id=46022965
| killerstorm wrote:
| There's a model of computation called 'interaction nets' /
| 'interaction calculus', which reduces in a more physically-
| meaningful, local, topologically-smooth way.
|
| I.e. you can see from these animations that LC reductions have
| some "jumping" parts. And that does reflect LC nature, as a
| reduction 'updates' many places at once.
|
| IN basically fixes this problem. And this locality can enable
| parallelism. And there's an easy way to translate LC to IN, as
| far as I understand.
|
| I'm a noob, but I feel like INs are severely under-rated. I dunno
| if there's any good interaction net animations. I know only one
| person who's doing some serious R&D with interaction nets -
| that's Victor Taelin.
| hmokiguess wrote:
| Speaking of Victor Taelin, what's the latest on
| https://higherorderco.com/ ? His work is really inspiring and
| amazing
| tromp wrote:
| > there's an easy way to translate LC to IN
|
| While easy, it sadly doesn't preserve semantics. Specifically,
| when you duplicate a term that ends up duplicating itself,
| results will diverge.
|
| There exist more involved semantics preserving translations,
| using so-called croissants and brackets, or with the recent
| rephrased approach of [1].
|
| [1] https://arxiv.org/abs/2505.20314
| dloss wrote:
| Some more example programs in Lambda Calculus here, including a
| compliant brainf#*k interpreter: https://justine.lol/lambda/
___________________________________________________________________
(page generated 2025-11-24 23:01 UTC)