Jan Stępień @jstepien@mastodon.social
Jan Stępień
boosted
One of the coolest things I've hacked together as a sort of side project the last few weeks is a property-based test for POSIX filesystems, which uses a simple in-memory model of mv, cat, etc to verify the safety of a real filesystem:
And here's an example bug it found in lazyfs--the original 1,998 ops it took to find, and the shrunk 5-op minimal reproducing case:
https://gist.github.com/aphyr/de84b509cf64c84c35ba40769063a05a#file-1-short-sh-L19-L23
At :clojureU, the #clojure conference formerly known as :clojureD
Look at this lovely blog post from Michelin. “[Java interop] was a huge advantage, as it helped to integrate seamlessly Clojure with our standard development stack: Java/SpringBoot.”
Now I’m only curious whether it was their tyre or restaurant guide division.
Jan Stępień
boosted
If you are fleeing the war in Ukraine and coming to the EU, you can find information on our webpage about:
🚆Travel
🚸Children protection
🎓 Education
🩺Healthcare
💼Jobs
🏠Housing
🔒Safety
🔗EU Stands with Ukraine. ➞ http://europa.eu/!VJY6fg
Advent of Code in K, day 18
/ ...continued:
unpack: {x[1_|1_|!#x]}
xpl: {:[#i:anyxpl x; unpack doxpl[(,w#b),x,,w#b;1+*i]; x]}
half: {(x,1+x)%2}
splmid: {-1!'b+i*/:(-b)+half@*x@&i:9<x}
dospl: {(y#x),splmid[x[y]],(y+1)_ x}
spl: {:[#i:&|/'9<x; dospl[x;*i]; x]}
red: {:[x~t:xpl x; :[x~t:spl x; x; t]; t]}
add: {red/-1!'x,y}
one: *(w-1) mag/(add/nums)[;w-2]
ids: i@&~=/'i:,/i,\:/:i:!#nums
sums: {add/nums[x]}'ids
two: (|/,/{(w-1) mag/x}'sums[;;w-2])
/ #adventofcode
/ https://www.janstepien.com/2021/aoc/
Advent of Code in K, day 18 ½
f: "18.txt"
pair: {m:x 1_ y; l:x (2+m[1]) _ y; (,m[0],*l;3+m[1]+l[1])}
parse: {:["["=*x; pair[_f;x]; (0$1#x;1)]}
b: -1
w: 5
arr: {:[@ z; (x#b),z,((y-x)#b); ,/_f[x+1;y]'z]}[-2;w-1]
read: {((#ns)%w;w)#ns:arr@*parse x}
mag: {(+/'(((#x)%2),2)#x*(#x)#3 2)}
nums: read'0:f
zero: {?b*~1!'b<x}
anyxpl: {(|:'(,':i)@&1=-':i:-2,&b<d:x[;w-1])}
xplmid: {(,t[0]),zero[a],,*1!t:z+(b<z) * +/'a*b<a:x[y]}
doxpl: {m:x@(-1 1)+y; ((-1+*y)#x),xplmid[x;y;m],(2+y[1])_ x}
/ #adventofcode ...
Advent of Code in K, day 17
f: "17.txt"
s: {y@{1+y+!x-(1+y)}':-1,&x=y,x}
in: {(0$')'(s["."]'*:'s[","]' 1_ s["="]@*0:x)[;0 2]}[f]
miss: {(x[1;0]>y[1])|x[0;1]<y[0]}
hit: {(~x[1;1]<y[1])&(~x[1;0]>y[1])&(~x[0;0]>y[0])&(~x[0;1]<y[0])}
step: {(y+x;(0|-1+*y),-1+y[1])}
sim: {:[hit[x;y]; (y;1); miss[x;y]; (y;0); step[y;z]]}
simv: {{sim[in]/x}\(0 0;x)}
dom: ,/t,\:/:-150+t:!350
peak: {:[*|*|x; |/x[;0;1]; -1]}
hits: {(*|*|x)}
sims: sims@&hits'sims:simv'dom
one: |/ |/' sims[;;0;1]
two: #sims
/ #adventofcode
Advent of Code in K, day 16
/ ...continuing from above:
op: {(op0;op1)[*y][x] 1_ y}
dec: {(num[3#x],id,p[1];(6+*p::[4=id:num[3#3_ x]; lit; op[dec]] 6_ x) _ x)}
versions: {x[0],:[@*2!x; !0; _f'2_ x]}
ops: (+;*;&;|;0;>;<;~)
walk: {:[4=x[1]; x[2]; ops[x[1]]/_f'2_ x]}
input: *dec bits@*0:file
one: +/,//versions input
two: walk input
/ This one had no chance of fitting into a sigle toot.
/ #adventofcode
Advent of Code in K, day 16 ½
file: "16.txt"
bin: {((4-#n)#0),n:{:[x<2; x; _f[x%2],x!2]} x}
bits: {:,/bin'{ d-7*9<d:(_ic x)-48 } x}
num: {(+/(|(-1+#x)(2*)\1)*x)}
litrec: {:[*x; (,4#1_ x),_f[5_ x]; ,4#1_ x]}
lit: {((5*#r)%4),num r:,/litrec x}
seqdec: { (,*d) , :[#*1!d:x y; _f[x; d[1]]; !0]}
ndec: { d: y z; (,((#z)-#d[1]),*d),:[x=1; !0; _f[x-1;y;d[1]]]}
op0: {l: num 15#y; (15 + l + 1; seqdec[x] l # 15 _ y)}
op1: {r: ndec[n:num 11#y;x] 11 _ y; (+/1,11,*:'r; 1_'r)}
/ #adventofcode, continued below
Advent of Code in K, day 15
inp: (0$')'0:"15.txt"
grow: {1+x!9}
full: ,/ 4 grow\ ,/' + 4 grow\inp
at: {(y[0]#x),(,(y[1]#x[*y]),z,(1+y[1])_ x[*y]),(1+*y)_ x}
init: {at[{:+/t*t:y-x}[0 0;t,t:-1+#x] + x - x;0 0;0]}
ns: {n@&((#x)>|/'n)&~0>&/'n:y+/:t,-t:(>:)\0 1}
step: {
i:(_abs y'n)>v:(_abs y c) + x'n:n@&0<y' n:ns[y] c:*z
d:{at[x;1_ y;*y]}/(,y),(v,'n)@&i
(at[d;c;-y c];{y@<x'y:?y}[d;(1_ z),n])}
go: {_abs *|*|*{-1+x*x}[#x]{step[x]/y}[x]/(init[x];,0 0)}
one: go inp
two: go full
/ #adventofcode
Advent of Code in K, a variant of APL, day 14
lines: 0:"14.txt"
split: {y@{1+y+!x-(1+y)}':-1,&x=y,x}
rule: {(`$*x;`$'(x[0;0],x[1];x[1],x[0;1]))}
rules: + rule' (split[" "]'2_ lines)[;0 2]
pairs: * rules
init: +/ pairs=/: `$' {(-1+#x)#x} {+(,x),,1!x}@*lines
produce: {x[1;*&y=*x]} rules
iter: {:+/{y*+/pairs=/:x}'[produce'pairs[&0<x]; x@&x>0]}
keys: (*|*lines),($pairs)[;0]
solve: {f:+/'(1,x iter/init)@=keys; -/(f@>f)[-1+1,#f]}
one: solve 10
two: solve 40
/ #adventofcode
/ https://www.janstepien.com/2021/aoc/
Advent of Code in K, day 13
lines:0:"13.txt"
s:{y@{1+y+!x-(1+y)}':-1,&x=y,x}
folds:{x:s["="]x;("x"=*|*x;0$*1!x)}'lines@&"f"=*:'lines
dots:{0$' s[","]x}'((-#folds)+-1+#lines)#lines
m1: {(x,2)#1 -1}
xfold:{x@&s:x[;1]>y;
d:((+/s),2)#0,2*y;
x[&~s],m1[+/s]*x[&s]-d}
fold:{:[*y; 1!'xfold[1!'x]y 1; xfold[x]y 1]}
one: #?fold[dots]folds 0
done: {fold[x]y}/((,dots),folds)
w:|/done[;0]
h:|/done[;1]
row: {(|/(!1+w)=/:x[&y=x[;1];0])}[done]
two: row'!1+h
/ #adventofcode
/ https://www.janstepien.com/2021/aoc/
Advent of Code in K, day 12
f: "12.txt"
all: p,1!'p:(`$')'{y@{1+y+!x-(1+y)}':-1,&x=y,x}["-"]'0:f
edges: all@&(~`start=all[;1])&~`end=all[;0]
big: {*(_ic"a")>_ic$x}
grow: {(edges[&(*x)=edges[;0];1]),\:x}
next: {done: d@&{(|/x=*y)}[y]'d:z 1
more: {g@&x'g:grow y} x
(#done;done,(,/more'((*z) _ z 1)))}
compl: {{(|/x=*y)}[x]'y}
fix: {:[y~b:x y;b;_f[x;b]]}
solve: {+/ (compl x) fix[(next y) x;(0;,,`start)][1]}@,`end
one: solve {(&/2>*/(,~big'?x),,#:'=x)}
two: solve {3>*/#:'=x@&~big'x}
/ #adventofcode
Advent of Code in K, day 11
f: "11.txt"
init: {0$'x}' 0:f
u: 1!
d: -1!
l: u'
r: d'
pad: {top,x,top:,(#*x)#0}@{0,x,0}'
unpad: {x' x y}@{1_ (-1+#x)#x}
adj: {unpad@+/1_{y x}\(pad[x];l;u;r;r;d;d;l;l)}
flash: {fl: (~y)&9<x; (x + adj fl; fl|y)}
after: {(*x)*~9<*x}
fix: {[f;a] :[a ~ b:f a; b; _f[f;b]]}
step: {[n;s] done: fix[{flash/x};(1+s; s-s)]; (+//done[1];after done)}
one: +/*:'{y x}\(,(0;init)),100#(step/)
all: {x*x}@#init
two: {n:0; while[all>*x; n+:1; x:step/x]; n}(1;init)
/ #adventofcode
Advent of Code in K, day 10
f: "10.txt"
lookup: {x[1;*&y=*x]}
nest: "([{<>}])"
err: 3 57 1197 25137
val: lookup (,nest),,{x,|-x}err
input: ({:[0>*x; x; y>0; y,x; y=-*x; 1_ x; y,x]}/val')'0:f
one: -+/,/{x@&{1>*x}x}'input
compl: lookup (,err),,1+!4
two: *((#s)%2)_ s@<s:{{y+5*x}/compl'x}'input@&{0<*x}'input
/ #adventofcode
/ https://www.janstepien.com/2021/aoc/
/ See you live on Twitch tomorrow at 14:00 CET?
Advent of Code in K, #9
f:"9.txt"
max:9
body:{|max,|max,0$'x}'0:f
top:,(#*body)#max
map:|top,|top,body
offs:({x!'map}'-1 1),{x!map}'-1 1
lows:&/map</:offs
one:+/1+,/{y@ x+&x#y}[#*map]'+(+lows),+map
maxat:{(y#x),(,(z#r),max,(z+1)_ r:x[y]),(y+1)_ x}
steps:,/-1 1*\:(1!)\1 0
rec:{r:search[x[1]]/y; ((*x)+*r;*1!r)}
dfs:{rec/((,(1;x)),(y,z)+/:steps)}
search:{:[max=x[y;z]; (0;x); dfs[maxat[x;y;z];y;z]]}
seeds:,/{(*x),'*1!x}'+(,!#lows),(,&:'lows)
two:*/3#a@>(a:((search[map]/)'seeds)[;0])
/ #adventofcode
adventofcode
s:{y@{1+y+!x-(1+y)}':-1,&x=y,x}
ssv:s" "
in:s["|"]'0:"8.txt"
ps:{
sg:{y=+/'x}[x]
on:{x@*&sg@ y}@ x
p3:x@*&3=+/'x&\:~p1:on[2]
s5:sg 5
s6:sg 6
p2:x@*&s5&+/'x&\:~(p3|p4:on[4])
p5:x@*&s5&+/'x&\:~(p2|p7:on[3])
p9:x@*&s6&~+/'x&\:(p2&~p3)
rm:{x@*&z=+/'x&\:y}[x@&s6&~(p9~)'x;p1]'!3
(rm@ 2;p1;p2;p3;p4;p5;rm@ 1;p7;:on[7];p9)
}
wi:{(+/+"abcdefg"=\:x)}
dc:{(+/(0,x)*|(#x)(10*)\1)}
one:+/(#:'=l@<l:#:',/ssv'in[;1]) 1 2 3 6
two:+/dc'{p:ps[wi'1_|ssv@*x];,/{&y~/:x}[p]'wi'1_ ssv@*1!x}'in
/ #adventofcode
#adventofcode in K, day 6, incl. a link to an RSS feed if that's what you're into
csv: {y@{1+y+!x-(1+y)}':-1,&x=y,x}[","]
init: -1+(#:'=(!9),0$'csv@*0:"6.txt")
gen: {(6#0),(x,0,x)}
iter: {:[n:*x;(1!x)+gen n; 1!x]}
live: {+/ x iter/init}
one: live 80
two: live 256
/ Part of the #adventofcode series
/ https://www.janstepien.com/2021/aoc/
#adventofcode in K, day 5, including a live coding session
file: "5.txt"
split: {y@{1+y+!x-(1+y)}':-1,&x=y,x}
input: {(0$')'split[","]'(split[" ";x])[0 2]}'0:file
len: {(|/{_abs x}'(-/x))}
hov: {(+/(0=)(-/x))}
points: {(len x)(((-/x)%len x)+)\x@1}
nondiag: input@&hov'input
count: {+/{1<#x}'=,/points'x}
one: count nondiag
two: count input
/ See the live coding session at
/ https://www.twitch.tv/videos/1225134274
/ #adventofcode
