RAramses0·Jan 7, 2026
My time to shine! https://news.ycombinator.com/item?id=45902088
References were Racket with the Racklog library¹. There's also Datalog² and MiniKanren, picat, flix. There were tons of good comments there which you should check out, but PySwip seemed like "the right thing" when I was looking at it: https://github.com/yuce/pyswip/
...documentation is extremely sparse, and assumes you already know prolog, but here's a slightly better example of kindof the utility of it:
https://eugeneasahara.com/2024/08/12/playing-with-prolog-pro...
...ie:
# ya don't really care how this works
prolog.consult("diabetes_risk.pl")
# ...but you can query into it!
query = "at_risk_for_diabetes(Person)"
results = list(prolog.query(query))
...the point being there's sometimes some sort of "logic calculation that you wish could be some sort of
Read the rest
regex", and I always think of prolog as "regexes for logic".
One time I wished I could use prolog was trying to figure the best match between video file, format, bitrate, browser, playback plugin... or if you've seen https://pcpartpicker.com/list/ ...being able to "just" encode all the constraints, and say something like:
valid_config = consult("rules.pl")
+ consult("parts_data.pl")
+ python.choice_so_far(...)
rules.pl: only_one_cpu, total_watts < power_supply(watts)
parts_data.pl: cpu_xyz: ...; power_supply_abc: watts=1000
choices: cpu(xyz), power_supply(abc), ...
...this is a terribly syntactically incorrect example, but you could imagine that this would be horrific code to maintain in python (and sqrt(horrific) to maintain in prolog), but _that's_ the benefit! You can take a well-defined portion and kindof sqrt(...) the maintenance cost, at the expense of 1.5x'ing the number of programming languages you need to expect people to know.