oliver
@eikopf.com
absolutely will not shut up about programming languages. apparently also now the calendar guy
(he/him)
(he/him)
if i never opened twitter how would i see high comedy like this
January 5, 2026 at 9:00 PM
if i never opened twitter how would i see high comedy like this
okay on a whim i tried using nix-shell, it seems a little insane not to provide this error message in the flake output
![oliver@pilatus in nix on main [!] took 33s
λ nix-shell -p racket
fetching path input 'path:/nix/store/xhgq6c23wj99i1yb77vjb12i95dkbf30-source'
warning: Nix search path entry '/nix/var/nix/profiles/per-user/root/channels' does not exist, ignoring
error:
… while evaluating an expression to select 'drvPath' on it
at «internal»:1:552:
… while evaluating strict
at «internal»:1:552:
(stack trace truncated; use '--show-trace' to show the full trace)
error: Package ‘racket-8.18’ in /nix/store/xhgq6c23wj99i1yb77vjb12i95dkbf30-source/pkgs/by-name/ra/racket/package.nix:120 is not available on the requested hostPlatform:
hostPlatform.system = "aarch64-darwin"
package.meta.platforms = [
"i686-cygwin"
"x86_64-cygwin"
"x86_64-darwin"
"aarch64-darwin"
"i686-freebsd"
"x86_64-freebsd"
"aarch64-freebsd"
"x86_64-solaris"
"aarch64-linux"
"armv5tel-linux"
"armv6l-linux"
"armv7a-linux"
"armv7l-linux"
"i686-linux"
"loongarch64-linux"
"m68k-linux"
"microblaze-linux"
"microblazeel-linux"
"mips-linux"
"mips64-linux"
"mips64el-linux"
"mipsel-linux"
"powerpc-linux"
"powerpc64-linux"
"powerpc64le-linux"
"riscv32-linux"
"riscv64-linux"
"s390-linux"
"s390x-linux"
"x86_64-linux"
"aarch64-netbsd"
"armv6l-netbsd"
"armv7a-netbsd"
"armv7l-netbsd"
"i686-netbsd"
"m68k-netbsd"
"mipsel-netbsd"
"powerpc-netbsd"
"riscv32-netbsd"
"riscv64-netbsd"
"x86_64-netbsd"
"i686-openbsd"
"x86_64-openbsd"
"x86_64-redox"
]
package.meta.badPlatforms = [
…](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:vt464ohreg6sglmnb4cuctmr/bafkreihwt75wgigzi55xkp44ryt4v3yeld5pilzpgb7y7fb3d4kdek7sgy@jpeg)
January 5, 2026 at 4:56 PM
okay on a whim i tried using nix-shell, it seems a little insane not to provide this error message in the flake output
![oliver@pilatus in nix on main [!] took 12s
λ sudo darwin-rebuild switch --show-trace --flake ~/.config/nix
building the system configuration...
warning: Git tree '/Users/oliver/.config/nix' is dirty
error: builder for '/nix/store/5zr4d473zigzcfgnq6gp8lh2agikppnp-racket-8.18.drv' failed with exit code 1;
last 25 log lines:
> checking for sys/types.h... yes
> checking for sys/stat.h... yes
> checking for stdlib.h... yes
> checking for string.h... yes
> checking for memory.h... yes
> checking for strings.h... yes
> checking for inttypes.h... yes
> checking for stdint.h... yes
> checking for unistd.h... yes
> checking iconv.h usability... yes
> checking iconv.h presence... yes
> checking for iconv.h... yes
> checking iconv is usable... yes
> checking for nl_langinfo (CODESET)... yes
> checking curses.h usability... yes
> checking curses.h presence... yes
> checking for curses.h... yes
> checking term.h usability... yes
> checking term.h presence... yes
> checking for term.h... yes
> checking curses is usable... yes -lncurses
> checking for libz... yes
> checking for liblz4... yes
> checking size of void *... 0
> Something has gone wrong getting the pointer size; see config.log
For full logs, run 'nix log /nix/store/5zr4d473zigzcfgnq6gp8lh2agikppnp-racket-8.18.drv'.
error: 1 dependencies of derivation '/nix/store/1a25g4xc1mfylpraqakjcmgxj5hpc32j-system-applications.drv' failed to build
error: 1 dependencies of derivation '/nix/store/9h9p4h95wfyyyxr2xywv2jk58i7rnvvy-system-path.drv' failed to build
error: 1 dependencies of derivation '/nix/store/dxzhp4z7p1ac3fnh3abjhpwgkpxaj3zn-etc.drv' failed to build
error: 2 dependencies of derivation '/nix/store/syvbgbalsp0n32q3b2awqjybgfxirbdi-darwin-system-25.11.688427b.drv' failed to build](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:vt464ohreg6sglmnb4cuctmr/bafkreig67u6miuupnhgse3v35bfnnkioef5v6un6cqjbjcxdrr47bp4jg4@jpeg)
“i was trying to spare you, you ungrateful cur!” they’re not sending their best folks
January 4, 2026 at 8:29 PM
“i was trying to spare you, you ungrateful cur!” they’re not sending their best folks
this might be worse actually
January 2, 2026 at 9:47 PM
this might be worse actually
why does the marketing for this thing have the ugliest code snippets i've ever seen
January 2, 2026 at 9:09 PM
why does the marketing for this thing have the ugliest code snippets i've ever seen
![; zone reference
3.3.6. Duration
Value Name: DURATION
Purpose: This value type is used to identify properties that contain
a duration of time.
Format Definition: This value type is defined by the following
notation:
dur-value = (["+"] / "-") "p" (dur-date / dur-time / dur-week)
dur-date
= dur-day [dur-time]
dur-time
= "T" (dur-hour / dur-minute / dur-second)
dur-week
= 1*DIGIT "W"
dur-hour
= 1*DIGIT "H" [dur-minute]
dur-minute = 1*DIGIT "M" [dur-second]
dur-second = 1*DIGIT "S"
dur-day
= 1*DIGIT "D"
Description:
If the property permits, multiple "duration" values are
specified by a COMMA-separated list of values.
The format is
based on the [ISO.8601.2004] complete representation basic format with designators for the duration of time.
The format can
represent nominal durations (weeks and days) and accurate durations (hours, minutes, and seconds).
Note that unlike
[ISO. 8601.20041, this value type doesn't support the "y" and "M" designators to specify durations in terms of years and months.
Desruisseaux
BFC 5545
Standards Track
iCalendar
[Page 35]
September 2009
The duration of a week or a day depends on its position in the calendar.
In the case of discontinuities in the time scale, such
as the change from standard time to daylight time and back, the computation of the exact duration requires the subtraction or addition of the change of duration of the discontinuity. Leap seconds MUST NOT be considered when computing an exact duration.
When computing an exact duration, the greatest order time components MUST be added first, that is, the number of days MUST be added first, followed by the number of hours, number of minutes, and number of seconds.
Negative durations are typically used to schedule an alarm to trigger before an associated time (see Section 3.8.6.3).
• additional content value encoding (i.e., BACKSLASH characte coding, see Section 3.3.11) are defined for this value type
Example: A duration of 15 days, 5 hours, and 20 seconds would be:
P15DT5HØM20S
A durati…](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:vt464ohreg6sglmnb4cuctmr/bafkreidzlo6n25mfiguseyl6sl3suh4muykypzq4irmq4mwkc6n3y34jre@jpeg)
in what world is this accessible to a person who doesn’t have any background in topology or type theory
December 23, 2025 at 12:53 PM
in what world is this accessible to a person who doesn’t have any background in topology or type theory
look at my fuckass hockey mascot i’m going to go insane
December 23, 2025 at 11:47 AM
look at my fuckass hockey mascot i’m going to go insane
what a wonderful community this video has attracted
December 23, 2025 at 9:27 AM
what a wonderful community this video has attracted
i hate using clearsky but like. what
December 15, 2025 at 10:39 PM
i hate using clearsky but like. what
i genuinely do not understand this attitude to euthanasia
December 15, 2025 at 10:33 PM
i genuinely do not understand this attitude to euthanasia
i am a walking national stereotype
December 11, 2025 at 10:03 AM
i am a walking national stereotype
yeah okay you can just do this instead
![solvePart2 :: [Vec3 Int] -> Int
solvePart2 ps = go Set.empty (length ps) . Seq.sortOn (uncurry d2) . pairs $ ps
where
go :: Set (Vec3 Int) -> Int -> Seq (Vec3 Int, Vec3 Int) -> Int
go _ pointCount Empty = error "unexpected end of list"
go seenPoints pointCount ((pl@(Vec3 lx _ _), pr@(Vec3 rx _ _)) :<| ps) =
let seenPoints' = Set.union seenPoints (Set.fromList [pl, pr])
in (if Set.size seenPoints' == pointCount then lx * rx else go seenPoints' pointCount ps)](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:vt464ohreg6sglmnb4cuctmr/bafkreihgy7da24er6jac2ydxbpx53dpdvti4k4pufywzl4z5rtahempdq4@jpeg)
December 8, 2025 at 2:02 PM
yeah okay you can just do this instead
![data Vec3 a = Vec3 a a a
deriving (Show, Ord, Eq)
-- | The squared Euclidean distance.
d2 :: (Num a) => Vec3 a -> Vec3 a -> a
d2 (Vec3 l1 l2 l3) (Vec3 r1 r2 r3) = (l1 - r1) ^ 2 + (l2 - r2) ^ 2 + (l3 - r3) ^ 2
parse :: String -> [Vec3 Int]
parse = map parseVec3 . lines
where
parseVec3 :: String -> Vec3 Int
parseVec3 s0 =
let (x, s') = span (/= ',') s0
(y, s'') = span (/= ',') $ drop 1 s'
z = drop 1 s''
in Vec3 (read x) (read y) (read z)
pairs :: [a] -> Seq (a, a)
pairs =
Seq.fromList
. concatMap (\(x :| xs) -> map (x,) xs)
. mapMaybe nonEmpty
. tails
-- the solution for part 1 would be much faster using a union-find data structure, but since there
-- doesn't seem to be an implementation of one in the GHC libraries i'm just using a set of sets
solvePart1 :: Int -> [Vec3 Int] -> Int
solvePart1 i =
foldl' (*) 1
. take 3
. sortBy (\lhs rhs -> compare (Down lhs) (Down rhs))
. fmap Set.size
. go []
. Seq.take i
. Seq.sortOn (uncurry d2)
. pairs
where
go :: [Set (Vec3 Int)] -> Seq (Vec3 Int, Vec3 Int) -> [Set (Vec3 Int)]
go circuits Empty = circuits
go circuits ((pl, pr) :<| ps) =
let (cs, cs') = partition (\set -> Set.member pl set || Set.member pr set) circuits
c = Set.unions (Set.fromList [pl, pr] : cs)
in go (c : cs') ps
solvePart2 :: [Vec3 Int] -> Int
solvePart2 ps = go [] (length ps) . Seq.sortOn (uncurry d2) . pairs $ ps
where
go :: [Set (Vec3 Int)] -> Int -> Seq (Vec3 Int, Vec3 Int) -> Int
go _ pointCount Empty = error "unexpected end of list"
go circuits pointCount ((pl@(Vec3 lx _ _), pr@(Vec3 rx _ _)) :<| ps) =
let (cs, cs') = partition (\set -> Set.member pl set || Set.member pr set) circuits
c = Set.unions (Set.fromList [pl, pr] : cs)
in ( if null cs' && Set.size c == pointCount
then lx * rx
else go (c : cs') pointCount ps
)
main :: IO ()
main = interact $ \…](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:vt464ohreg6sglmnb4cuctmr/bafkreihnqyzfhsowsofnwdd5hutzn6akdil3w6v5k2wanpvq5cloxko2de@jpeg)