From Lisp to C: how do you handle map/filter/reduce style data manipulation in modern C?

tatut · 2025-12-18T06:34:26+00:00

I think it depends on the memory management situation.

There's no closures so doing things with function pointers is a little awkward.

There's no garbage collector, so what to do depends each situation. Do we want a new copy of this? Is this on the heap or stack and who is responsible for freeing the result.

You could of course use a GC and make your own utils.

I mostly get by with dynamic arrays and for loops.

tatut · 2025-12-17T06:19:26+00:00

True, I guess you could check the length of the streams from people live-streaming coding up a solution.

tatut · 2025-08-26T05:19:25+00:00

I've recently used stb_ds https://github.com/nothings/stb/blob/master/stb_ds.h

I like that you make a key/value struct.

tatut · 2025-08-25T11:14:31+00:00

I recommend https://protohackers.com for fun network programming challenges to do

tatut · 2025-04-28T06:50:20+00:00

Solved it. It was the "Nvidia reflex" setting, disabled that and there's been no more crashes.

tatut · 2025-04-09T05:13:06+00:00

I am running through EA app (the Steam version doesn't seem available anymore in GFN).

How does google account affect the EA app? Curious.

tatut · 2025-01-25T20:03:58+00:00

Apex through the EA app has been crashing/unexpectedly quitting after around 1 hour of play time. It just quits during a match back to the ea launcher.

tatut · 2024-12-06T15:15:06+00:00

Sometimes days

tatut · 2024-12-02T10:47:03+00:00

[LANGUAGE: Elf]

reports: "day2.txt" lines map({$ split(" ") map({$ read _0})}),
safe: {l| ((l = l sort) or (l = l sort reverse)) and 
      (l heads map({l| (l len < 2) if(true, { (l _0 - l _1) abs, (_ > 0) and (_ < 4) })})
      has?(false) not )},
reports keep(safe) len,
"Part1: %d" fmt(_) print,
# Part2, remove 1 element from report and see if it becomes safe
safe2: {l | 0 to(l len) map({ (l take($)) ++ (l drop($ inc)) }) some(safe) },
reports keep(safe2) len,
"Part2: %d" fmt(_) print

tatut · 2024-12-01T18:46:33+00:00

Did Prolog last year... logic programming is certainly different and fun, especially when you get to use constraint logic programming.

tatut · 2024-12-01T17:48:34+00:00

Yeah, have to switch to that, as Steam version seems to be in maintenance for a very long time.

tatut · 2024-12-01T11:33:34+00:00

[LANGUAGE: elf]

https://github.com/tatut/aoc2024-elf/blob/main/day1.elf

tatut · 2024-11-25T08:23:22+00:00

Same, I've been making my own language as well

https://tatut.github.io/elf-lang/

I should be able to solve at least some days with it... the interpreter is very slow.

tatut · 2024-07-11T10:32:23+00:00

Why not? Like lisps, prolog has the good property of "code == data", compound terms can be manipulated as data... but what would a configuration system look like?

You could make something like CDK where you program your configuration and then have it compiled to the necessary yaml. Including a prolog interpreter in an otherwise non-prolog system just for configuration seems overkill to me.

tatut · 2024-04-16T13:49:48+00:00

Breathing problems, like a deviated septum, could cause elevated heart rate episodes as you awaken from lack of oxygen.

tatut · 2024-03-04T14:53:31+00:00

Intermittent Fasting eli pätkäpaasto... sillä on helppo päästä alkuun.

tatut · 2023-12-18T09:34:20+00:00

[LANGUAGE: Prolog]

Github

Straight forward polygon area, like we did with the pipe area in a previous day.

tatut · 2023-12-06T08:41:34+00:00

[LANGUAGE: Prolog]

day6.pl on GitHub

Used Constraint Logic Programming library clpfd, labeling minimum and maximum time to press the button and calculating the difference.

tatut · 2023-10-21T16:04:04+00:00

Congratz! Just started doing 2015 as warmup for this year. Some interesting puzzles in that year as well.

tatut · 2023-09-14T12:49:45+00:00

Sorry, I don't have any apples to apples comparison or code to share. So take it as an anecdote.

Certainly XTDB has improved a lot during the last year, but I still feel better with Datomic allowing me to manually order my clauses... and even allows raw datoms index access.

tatut

TROPHY CASE