The Nineteenth Byte

user202729

10:02 AM

... Stack?

caird coinheringaahing

Yeah, I already have the obvious ones, stack, tape and registers

user202729

How is "register" a memory model?

"register and RAM"?

Grid? (like Hexagony memory model, but not necessary hexagonal grid)

caird coinheringaahing

@user202729 As in integers that can interact with each other via commands, but aren't stored in a tape/stack (i.e. a set number of registers)

@user202729 Yeah, grid and deque are the other two I've got

user202729

@cairdcoinheringaahing Infinite integers? Creating data structures in such a language would be hard.

caird coinheringaahing

@user202729 Infinite as in arbitrary precision?

user202729

10:06 AM

Yes.

(otherwise it's not TC)

Cows quack

@LeakyNun so the function takes in a (nat → bool) function and returns a nat, or does it take a nat and bool and return nat`

Leaky Nun

@Cowsquack the former

(the latter would be (nat x bool) -> nat or nat -> (bool -> nat) :P

user202729

But what is "nat"?

Leaky Nun

@user202729 yes

@user202729 natural numbers

user202729

How is this decidable? ....

Leaky Nun

10:14 AM

it is :P

Cows quack

can you give examples?

user202729

So a (nat -> bool) is equivalent to a subset of nat...

and a (nat -> bool) -> nat maps each subset of nat to a natural number.

There are uncountably many subsets...

Leaky Nun

@Cowsquack so an example of (nat -> bool) -> nat would be λ t, if t(0) then 1 else 0

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

@Downsheep keep value, cast isn't bitcast. it should throw exception or something if out of range

Leaky Nun

@user202729 right

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

10:16 AM

@Downsheep idk, it isn't in any doc?

Cows quack

@LeakyNun so if the input to (nat → bool) is 0, then (nat → bool) → nat gives 1

user202729

I think the strategy is to pass a specially constructed t into the box and...

Leaky Nun

@Cowsquack wait what

if the given function nat -> bool returns true when I input 0, then I return 1

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

@user202729 :|

user202729

(i.e., for that example, it maps all subsets containing 0 to 1, all other subsets to 0)

Leaky Nun

10:19 AM

>> f=t=>t(0)?1:0
<< t=>t(0)?1:0
>> f(k=>k>3)
<< 0

javascript demonstration

Cows quack

@LeakyNun of yeah because (nat → bool) → nat doesn't know what the first nat is

user202729

Must the function t passed in be pure?

Leaky Nun

@user202729 yes, guaranteed to halt at every input and give bool

user202729

I meant the nat -> bool passed as input.

Cows quack

s/of/oh/

user202729

10:21 AM

Wait a minute, how is "guaranteed" related here?

Leaky Nun

@user202729 yes, halting at every input and give bool

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

@LeakyNun is this actually doable in a finite amount of time

Leaky Nun

@Ｕｎｉｃｏｄｅ-ｏｎｌｙ yes

user202729

(for example, can the function passed in be input => {global list.push(input); return 1;})

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

hmm.

Leaky Nun

10:27 AM

@user202729 does it have a turing-machine equivalent?

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

so basically you need to pass in a function/functions to determine the entire code of the functions, or pass in a set of functions that cover every combination of inputs?

Leaky Nun

what do you mean?

user202729

Pass in a function (nat -> bool).

caird coinheringaahing

@Ｕｎｉｃｏｄｅ-ｏｎｌｙ Why are you still Unicode? Even the duck has left SE

4

Ｕｎｉｃｏｄｅ-ｏｎｌｙ

you need to somehow be sure they do the exact same thing. so you need to somehow figure out either 1. what they do, or 2. cover all possible cases

@cairdcoinheringaahing sheep and bald star trek dude are still here, but good point

user202729

10:31 AM

passata changed back...

ASCII-only

@cairdcoinheringaahing better?

@user202729 sorry brainfart

caird coinheringaahing

@ASCII-only Much :P I can type your name now :P

@ASCII-only "bald star trek dude" facepalm

ASCII-only

help my avatar is still broken

nvm

user202729

Help why does TIO interpret J input as commands

Cows quack

IIRC the input is fed to the repl

user202729

10:34 AM

tio.run/##y/oPBIbahlzaOloA

Yes it is.

ASCII-only

@user202729 you could say the same about APL

Cows quack

so that's why

user202729

But how can I read stdin then

caird coinheringaahing

Arguments?

user202729

@ASCII-only A special keyboard is enough. I don't need two.

Exit code 100 -- argument list too long.

Leaky Nun

10:35 AM

@user202729 you're given two functions (nat -> bool) -> nat

user202729

I will do that later...

Cows quack

@LeakyNun if the (nat → bool), say, only returns true if nat is above 1E100, then what are you going to do

user202729

@Cowsquack But that's finite...

Leaky Nun

@Cowsquack you aren't given a function nat -> bool

Cows quack

don't you have to check for every n ∊ nat?

Leaky Nun

10:37 AM

@Cowsquack you aren't given a function nat -> bool

user202729

The naive algorithm is to check for all (nat -> bool)

ASCII-only

@Cowsquack you pass the function in

user202729

and there are uncountably many.

ASCII-only

yep

Cows quack

and that function takes in a nat

ASCII-only

10:37 AM

@Cowsquack yeah the function you pass in has to be nat -> bool

takes in nat, returns bool

Cows quack

oh I see

then you pass nat=>!nat to the functions and test for inputs 0 and 1

Leaky Nun

the CMC asks you to write a function of type ((nat -> bool) -> nat) -> ((nat -> bool) -> nat) -> bool

ASCII-only

@Cowsquack what does that do

Leaky Nun

to clarify any ambiguity

ASCII-only

@LeakyNun wait. so you only have the composition of f and g???

Cows quack

10:42 AM

@ASCII-only if the outputs are the same then you know they're the same

Leaky Nun

@ASCII-only composition?

Cows quack

I guess you have to explain lean's notation

Leaky Nun

I mean

(((nat -> bool) -> nat) x ((nat -> bool) -> nat)) -> bool

I don't think there's any ambiguity here

user202729

@Cowsquack What does ! do in this case?

Cows quack

give false if 0, true otherwise

user202729

10:45 AM

.... So, because it's guaranteed that both f and g hatls, they must only examine finitely many inputs in all cases.

ASCII-only

@user202729 that's true. but we're probably trying to find a better solution than every possible combination :P

user202729

@ASCII-only Every possible combination will run infinitely.

So find any solution that will evantually halt is strictly better.

Cows quack

@LeakyNun does my function work?

Leaky Nun

where's your function?

user202729

@Cowsquack What's your function?

Although I already asked this, I don't understand the answer.
Can the (nat->bool) that **we** pass into the **given** f and g be impure?

Cows quack

10:51 AM

not←0∘=
equals←{(g∘¨≡f∘¨)(not 0 1)}

apl

H.PWiz

@Cowsquack not 0 1 seems redundant

Cows quack

input functions are f and g

user202729

@Cowsquack Translation to other languages please?

Leaky Nun

@user202729 I don't think so

otherwise it wouldn't be a function nat->bool

Cows quack

does it work LeakyNun?

or am I still misunderstanding something

Leaky Nun

10:54 AM

I can't understand your code

user202729

I can't understand your code

Cows quack

>_>

@H.PWiz now that I look into it, f and g take in a bool, so would I have to do f∘not and g∘not?

H.PWiz

@Cowsquack g and f should each be operators, not functions (in APL speak)

They take a functional argument

New Main Posts

1

Q: Zero-sum counting

Write a program or function that given n ≥ 1 returns the number of solutions to ±1 ± 2 ± 3 ± ... ± n = 0. For n = 6 there are no solutions, so the answer is 0. For n = 4 there are two solutions, so the answer is 2 (the two solutions are 1 - 2 - 3 + 4 = -1 + 2 + 3 - 4 = 0). This is OEIS sequence...

user202729

@Cowsquack What...?

No, f and g take in a nat->bool.

Cows quack

10:56 AM

I will translate it once I fix it

user202729

codegolf.stackexchange.com/…

Cows quack

how do you define an operator dfn again?

H.PWiz

@Cowsquack ⍺⍺

Cows quack

oh right, ⍵⍵ was borking

@H.PWiz ∧/(0∘=a≡0∘=b)¨0 1

a and b are operators

translation: so let's call the two ((nat → bool) → nat) functions a and b

this feeds the function f=x=>x==0?true:false into a and b

H.PWiz

@Cowsquack I don't think that s valid. Let a←{2×⍺⍺ 2} and b←{3×⍺⍺ 2}. This says that they are equal

Cows quack

11:06 AM

and gives the input 0 and 1 to (a f) and (b f)

ah I see

orlp

11:24 AM

@LeakyNun codegolf.stackexchange.com/a/161133/4162

:P

Leaky Nun

@orlp nice

very clever

user202729

12:04 PM

@LeakyNun Huh? ...

@Cowsquack x==0?true:false ...

Almost as bad as a

switch (boolean_variable) {
case true:
// ...
break;
case false:
// ...
break;
}

Cows quack

I wanted to make it explicit, because you asked what !x was

user202729

Anyway, I also don't think that they're valid.

But I still feel that this is unsolvable.

Cows quack

@user202729 yeah, HPWiz already said that

user202729

Let's say, if our function A is given f == g == (x => 1) and returns true, we can record the (finite) set S of (nat -> bool) functions fed into f.

And then give A the function f == (x => 1), g == (x => (if there is any function (y) in (S) that coincides with (x) the first (n) values then 1 else 0))

where n is the first value such that 2^n>|S|

then g != f and our function can't determine that.

Leaky Nun

12:40 PM

@user202729 what

moonheart08

12:53 PM

@user202729 why not use !x as an example instead?

> (x==0?true:false)?false:true

user202729

1:34 PM

Is my reasoning wrong? That appears to prove the function is uncomputable.

moonheart08

..oh, i didn't scroll down

New Sandboxed Posts

1

A: Sandbox for Proposed Challenges

Find me in Pi codegolfpi Challenge : Pi is supposed to be infinite. That mean every number is contained inside the decimal part of pi. Your task will be to take a positive number on input and return the position of this number in pi digits on output. For example, if the input is 59, we'll ret...

user202729

(@LeakyNun )

Leaky Nun

1:53 PM

@user202729 could you elaborate on why our function can't determine that?

user202729

Slight mistake. the set of S are the functions fed into g, not f.

Leaky Nun

sure

user202729

Because... A only give g the functions in S, so all of its output are 1.

And because there are more possible tuple of boolean values y(1),y(2),...,y(n) than number of functions in S, there exists a tuple that isn't in those produced by a function in S, so there exists a function that g returns 0.

caird coinheringaahing

Ha, I've had a total of 299 stars on my messages in TNB :P

user202729

don't star one more or it would be 300

J. Sallé

2:01 PM

@user202729 too late

@cairdcoinheringaahing congrats on the 300 stars :p

Should probably be a badge or something

caird coinheringaahing

It seems better to star my existing message on the starboard, rather than a totally new one, that will probably only get one star :P

user202729

Now there are misinformation on the starboard. @J.Sallé Your fault.

(actually outdated information)

J. Sallé

I regret nothing

caird coinheringaahing

@J.Sallé Given Dennis has >4500, I think 300 is nothing :P

J. Sallé

@cairdcoinheringaahing well, he should have 15 of those badges then >.>

Soaku

2:05 PM

Ugh, had to disconnect my primary screen, when got it back it doesn't detect any sources. Windows does detect it, can read it's resolution and seems to send signals to it, but the screen doesn't react. No buttons on the screen help, because they require signal to be sent to it first (which is completely stupid, you can't configure it without source, you can't even change the source). I tried unplugging both the primary and secondary string, but no success.

caird coinheringaahing

@J.Sallé 1000 stars seems more likely to be a badge, given that only 20 PPCGer's have that in TNB

J. Sallé

Fair enough

Dennis

@J.Sallé I support this idea.

New Main Posts

0

Q: Pi got your number

Challenge : Pi is supposed to be infinite. That mean every number is contained inside the decimal part of pi. Your task will be to take a positive number on input and return the position of this number in pi digits on output. For example, if the input is 59, we'll return 4 Here is why : we wil...

code-golf pi

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Title: Lossless "Compression" Implement the following lossless pseudo-compression pseudo-algorithm and its decompressor; scored by the number of bytes after you've put your source-code for both through your own implementation of the compressor algorithm, described below: Algorithm Description ...

Dennis

2:18 PM

@user202729 Because if you don't exit your program (with, e.g., exit ''), the J interpreter drops to a REPL at the end of it, so unconsumed input will be treated as REPL commands. STDIN still works though.

caird coinheringaahing

CMC: Output 26 without numbers in your source code

Dennis

Jelly: ØAL. Pyth: lG.

caird coinheringaahing

Whatever this language will be called: #++[>+[>+++<-]<-]++,>>,

user202729

”<26th char here>O

dzaima

@cairdcoinheringaahing zl or '⁸ in SOGL

user202729

2:29 PM

Doesn't work.

“ȷ‘

DJMcMayhem

@cairdcoinheringaahing V, 5 bytes: ¬azø.

Port of Dennis's solution

Fatalize

@cairdcoinheringaahing Brachylog, 2 bytes: Ạl

wastl

Does someone know how to make a code block with an empty last line?

caird coinheringaahing

@wastl Use <pre> tags (like so‌)

user202729

~~in where?~~ SE? Yes, but be careful to escape < and >.

J. Sallé

2:32 PM

@cairdcoinheringaahing APL (Dyalog) 3 bytes: ≢⎕A

wastl

thanks

user202729

(< and >)

Dennis

@wastl Use the auto-formatter on TIO. Also works for lines containing only spaces/newlines.

user202729

Can anyone spot any improvement in this answer? (Haskell)

Pavel

@Dennis When I use that, it shows the trailing empty line in the preview when I go to post my answer, but it disappears once the answer is actually posted.

Dennis

2:46 PM

You might have to disable syntax highlighting for that post.

Pavel

Ah, that makes sense

quartata

@Downsheep what's :> in VSL, I see it reserved

Dennis

That's clearly the evil operator.

Luis Mendo

Is it just me, or linking this right in my answer feels a bit rude? Not that I really care, but I'm a bit surprised

caird coinheringaahing

Yeah, that seems a little arbitrary, and more of a better fit under the challenge

user202729

2:50 PM

... sorry

Luis Mendo

No problem! I just had never seen that linked directly in an answer

as if saying "this answer is crap" :-)

user202729

I was going to reply to Therandomguy's comment above, but I think that

it can be useful for someone else.

quartata

@cairdcoinheringaahing only 200 stars?TNBDE says I have like 2100

here, try this query:

caird coinheringaahing

@quartata I have been only around for 13 months :D

quartata

select sum("transcriptAnalyzer_message".stars) from "transcriptAnalyzer_message" left join "transcriptAnalyzer_user" on "transcriptAnalyzer_message".user_id = "transcriptAnalyzer_user".id where "transcriptAnalyzer_user".uid = <your chat id>

Pavel

2:56 PM

0/10 LOWERCASE SQL

quartata

no it's a good thing

caird coinheringaahing

Aww, 296, I was off by 3 :/

user202729

+1 for lowercase sql.

Dennis

Screaming while programming will distract your coworkers.

12

quartata

it's probably just out of date

anyways, I wonder if it's because of a few highly starred messages or many one starred messages

Dennis has 4500 o_O

caird coinheringaahing

2:59 PM

@quartata My stars range from 1 to 23, so its a bit of both, by the looks of it :P

J. Sallé

5/7 lowercase sql is the only possible sql

Dennis

Are we sure that's correct? I'm not even here that often.

Pavel

@Dennis Yeah but people star your messages all the time pretty much at random

caird coinheringaahing

@Dennis What does this look like for you? I'm guessing lots of 10-30 star posts

@Pavel Case in point :D

Dennis

Still, I've posted just over 27,100 messages. That's 0.17 stars per message.

user202729

3:03 PM

I only have 31 stars, ranges from 1 to 5.

Poke

@Dennis Not if I've already conditioned them to accept my workflow

caird coinheringaahing

CMP: What's your most-starred message?

Mine with 23

Dennis

How can I tell?

user202729

Dennis has too many starred messages that finding manually is too tedious.

user56656

I'm at 24 on this

user202729

3:07 PM

chat.stackexchange.com/rooms/info/240/the-nineteenth-byte/…

New Main Posts

0

Q: ASCII-art to numbers

Inspired by Digits in their lanes Input: An ASCII-art of width ≤ 11, consisting of spaces and #. (You can choose any two distinct characters instead.) Example: # ### # # # # # # # # # ### # # ### # ########### # # # ...

code-golf ascii-art

caird coinheringaahing

@Dennis I just checked the starred messages posted by me, and scanned over them. Not sure if that'd work for you though :/

Pavel

I have too many starred messages to dig through them all.

Dennis

@cairdcoinheringaahing There's 22 pages.

caird coinheringaahing

Maybe TNBDE might help?

Dennis

3:08 PM

It's probably this one, at 57 stars.

Dec 19 '16 at 2:24, by Dennis

The next person who abuses his privileges to get hats will get a suspension instead, until the day after Winter Bash.

@cairdcoinheringaahing I have zero SQL skills.

H.PWiz

2 stars. Also no one did solve it (it's pretty easy)

Dennis

Close third(?) was, sadly, posted for the same reason.

Dec 16 '15 at 23:08, by Dennis

Hats are fun, but reopening questions that should remain closed, just to collect a hat, is taking things too far. Please refrain from doing this.

DJMcMayhem

Aug 2 '17 at 16:55, by DJMcMayhem

With 25

Pavel

CMC: TNBDE query to determine average star count per message for all users sorted greatest to lowest

user202729

No onebox please

caird coinheringaahing

3:12 PM

Aug 2 '17 at 16:55, by totallyhuman

and that is the 25000th starred message :D

:D

Poke

I will admit that I laughed at this: blog.sebastian-daschner.com/entries/maybe_keyword_in_java

J. Sallé

@DJMcMayhem that image is gold

user202729

@Poke (edit ninja'd)

DJMcMayhem

@J.Sallé thanks

@Pavel It'll almost certainly end up being someone with the fewest messages

Pavel

I just want to see if it's Dennis

Wat

totallyhuman

3:15 PM

Um.

Ookay.

caird coinheringaahing

That's the first time I've flagged a chat message :P

Pavel

Glad that's over with

user202729

What happened? Spam?

Dennis

troll

DJMcMayhem

@Pavel Dennis has posted 54145 messages in chat... I have a hard time believing he'll have a high average

Dennis

3:21 PM

That's all of chat btw. Roughly half of them were posted here.

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Binary path For an integer n that satisfies n > 0, write its value as a right-descending path based on its binary representation. Rules The first set bit (most significant) is always in the top-left corner. When the next bit is set (a 1), draw with a character on the next line in the same col...

user56656

I'm planning on posting this in the next hour, any last thoughts? Is everything crystal clear?

4

A: Sandbox for Proposed Challenges

(A → B) → (¬B → ¬A) proof-golf Well I think it is about time we have another proof-golf question. This time we are going to prove the well known logical truth (A → B) → (¬B → ¬A) To do this we will use Łukasiewicz's third Axiom Schema, an incredibly elegant set of three axioms that are comp...

... and posted

J. Sallé

> This account is temporarily suspended network-wide. The suspension period ends on Mar 31 '28 at 15:17.

Regarding the troll ^

That's a nice "temporary" suspension.

moonheart08

I wonder if stackexchange/stackoverflow will still be the goto in 10 years

J. Sallé

3:38 PM

My thoughts precisely.

New Main Posts

3

Q: (A → B) → (¬B → ¬A)

Well I think it is about time we have another proof-golf question. This time we are going to prove the well known logical truth (A → B) → (¬B → ¬A) TeX To do this we will use Łukasiewicz's third Axiom Schema, an incredibly elegant set of three axioms that are complete over propositional logi...

logic proof-golf

caird coinheringaahing

@J.Sallé First rule of suspensions is that we don't talk about suspensions, as cliché as that sounds

@NewMainPosts In the URL: a-→-b-→-¬b-→-¬a

J. Sallé

@cairdcoinheringaahing I just thought the wording was funny. I'd never imagine something "temporary" to be 10 years long, but it does make sense, of course.

mbomb007

4:17 PM

Someone should write a challenge on this:

Non-Integer Bases

totallyhuman

@NewMainPosts So the point is to prove that the third axiom is not an implication, it's a biconditional?

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Text -> Brainfuck Well I just can't find it and post here waiting for someone mark it duplicate

caird coinheringaahing

@NewSandboxedPosts ಠ_ಠ That's just lazy

user202729

But it's a dupe anyway (right?)

DJMcMayhem

It's been done with brain-flak, but I don't know if it's been done with brainfuck

(and the two are radically different)

Emigna

4:22 PM

@user202729 it is

user56656

@totallyhuman In essence yes.

but we haven't defined what a biconditional is so you just prove it going the other way.

user202729

@cairdcoinheringaahing Putting effort into a something that will soon be deleted sounds like a waste too.

caird coinheringaahing

@user202729 If you look at it that way, isn't this entire site a waste?

user202729

How is "this entire site" related to "soon be deleted"?

Also... participating on the site is fun.

(depending on your definition of "waste", it may be)

Are chat suspension site-specific or network-wide?

caird coinheringaahing

Almost nothing on this site has any real impact, we're just a bunch of people writing horrible code for fun. We are, essentially, wasting our time. However, we can choose to waste our time effectively and making the site pleasant for others, or we can post one liner posts that mean nothing to anyone else, and take up space for others. Most of us, thankfully, choose the former

7

@user202729 Network wide IIRC

user202729

4:29 PM

Sure, posting lazy challenges on main is bad, but not in the sandbox.

caird coinheringaahing

Why isn't it bad in the Sandbox?

J. Sallé

@cairdcoinheringaahing well, I've learned a bunch of stuff while "wasting my time" here. Mostly APL but a lot of logic as well.

user202729

The whole point of the sandbox is to post incomplete or need-review challenges...

J. Sallé

So that's not a waste in my books.

caird coinheringaahing

@J.Sallé Fair point

user202729

4:31 PM

In this particular case the OP is just asking "if this is a dupe I will delete it" something like that.

caird coinheringaahing

@user202729 Incomplete, not "needs a complete rehaul to be considerable on main"

@user202729 Then ask if said challenge is a duplicate in chat, before posting. Or go find the duplicate yourself, especially when it's that blatant

DJMcMayhem

@user202729 Yes, but it's not the place to say "Hey, is this a dupe?" without speccing the challenge at all. That's what chat is for

caird coinheringaahing

Also, ninDJ'ed again

DJMcMayhem

It particularly irks me when people treat the sandbox as a dumping ground: "Oh, it doesn't need to be totally finished before I post it here, so I'll just post the bare minimum I can get by with and edit it later". Seems lazy and unproductive to me

2

user202729

@DJMcMayhem @cairdcoinheringaahing Not everyone knows about chat. Of course. Saying "that is what chat is for" is not a reason.

DJMcMayhem

4:33 PM

The most effective way to use the sandbox is to write it up entirely as if you were about to post it, and then look for minor loopholes or inconsistencies

caird coinheringaahing

@user202729 I4m2 has been, and talked, in chat before

user202729

search chat messages Again, not a reason. Although in this particular case...

DJMcMayhem

Not a reason for what?

Cows quack

4:58 PM

@cairdcoinheringaahing 22 chat.stackexchange.com/transcript/240?m=37522673#37522673

Adám

5:09 PM

Announcement: APL Cultivation in 20 minutes.

Cows quack

@DJMcMayhem can n be taken in unary?

(likewise can output be given in unary?)

DJMcMayhem

Uhhhh

Given that I haven't thought about that CMC for like a year, I'll go with yes

Cows quack

whoops, I saw someone reply to that cmc and thought it was recent >_>

oh I see, I clicked on wheat wizard's most starred message and found a cmc nearby

Anonymous

Customer: Feature X sucks. Can it be made better?
Me: *works on feature overhaul for 2 weeks, achieves perfection*
Customer: Cool! But the font is kinda small even though it's the same exact font used basically everywhere else - can it be made bigger?
Me: *considers day drinking*

Downsheep

@cairdcoinheringaahing that’s not true. While most things here don’t have direct impact, I’ve developed so many valuable skills here. With those skills I have been able to create things that have an impact and I’m sure others have too

Anonymous

5:25 PM

Making Seriously/Actually and PPCG v2 made me git gud at unit tests, which impressed my now-boss when I was interviewing for my current job

Pavel

6:06 PM

@Mego Did you not unit test before?

J. Sallé

@Mego my life in a nutshell.

Riker

@Pavel they take a respectable amount of effort to enact, which ppcg is not known for encouraging

J. Sallé

I'm developing an application that makes financial reports based on the systems the company I work for sells. The whole point of the application is so our clients don't need to use excel for this kind of stuff anymore.

First meeting with the client:
C: "Can we get an 'Export to Excel' button?"
Me: *facedesk*

Riker

that sounds very saddening

moonheart08

7:07 PM

and took over the entire map

..highway doesn't handle it's two sides meeting very nicely

literal river of ants

orlp

7:26 PM

8

Q: (A → B) → (¬B → ¬A)

Well I think it is about time we have another proof-golf question. This time we are going to prove the well known logical truth (A → B) → (¬B → ¬A) TeX To do this we will use Łukasiewicz's third Axiom Schema, an incredibly elegant set of three axioms that are complete over propositional logi...

logic proof-golf

I'm looking at this question, at the example

A → (B → A)                                     L.S.1
A → ((B → A) → A)                               L.S.1

step 1 is logical, it directly introduces axiom 1

but step 2 I'm at a loss

how does axiom 1 give that?

H.PWiz

Let (B → A) = ψ

orlp

but you don't have (B -> A)

H.PWiz

So, why would you need (B → A)?

orlp

I thought you did

for deduction

user56656

Nope it can be any statement

orlp

7:30 PM

that it's substitution of what you already have

alright

makes sense in hindsight

Giuseppe

@J.Sallé I feel you; I'm doing something similar, working on insurance products, doing all this stuff to dynamically evaluate risk and all the users want is a static PDF or a powerpoint deck

user56656

I'll make it clear in the question.

New Main Posts

0

Q: Remember the Tower Bloxx?

I have recently thought of a wonderful relatively old mobile game, called Tower Bloxx. Alhough I'm not really old myself, but it reminded me of childhood and school :) So this my challenge is a kind of a reference to that good game! I have (hopefully) looked into any tower question on PPCG an...

code-golf ascii-art

New Main Posts

8:28 PM

2

Q: Integers in Base Pi

Background: Pi (π) is a transcendental number, and therefore it has a non-terminating decimal representation. Similar, the representation doesn't terminate if written in any other integer base. But what if we wrote it in base π? Digits in decimal represent powers of 10, so: π = 3.14… = (3 * 10...

code-golf base-conversion pi

Newly Featured Questions

224

Q: Paint Starry Night, objectively, in 1kB of code

Note: Anders Kaseorg has been awarded the accept for now, to draw attention to his great answer, but the challenge is by no means over! There is still a 400 point bounty in the offering for anyone who takes the top score without using built-in compression. Below is a 386x320 png representation ...

code-challenge graphical-output compression

Pavel

Question: if I want to bind page up/down to mouse scroll wheel, how might I do that on Linux? I know of AHK on Windows.

Riker

@NewlyFeaturedQuestions wow, that's nice of the guy

H.PWiz

@user56656 I don't know how long you're expecting solutions to be for the proof-golf challenge, but my unfinished solution is currently too big for the Prolog program to read it. Admittedly, I have gone round the houses a bit, but it's not that long

user56656

Oh no. could you send me the proofgram so I could try to debug the Prolog?

H.PWiz

8:41 PM

It appears to just be a size issue. see https://tio.run/##7VXbbtpAEH3nK7aWKnbVsVWSt7YgmUoVlagS1XlwBMhxwwKWjG3ZG2hF8u10xmvHFxzaD0BI9u7MOWdmdmdMksZhvDazfXA8@ire8tnk@W4hmGmO2GyygMNjvJSe@pNIPgE/TDa@eIEceCesXsH4B97q9faZRiyscskNZnw25soQsM8QEcWKu1rHMA20QaZ8JbcyUh46EBGsuAv3GtLwEdgwR23SPZLev0G616Qv3ZFq@7xCV2iBYmPVATpv7dfrhruIXxTG83CFLc9AGA242wCeVknwCt9UbyjXVEvRDkEU@@UvvQo6K68SL6rlcau@cPGe3flw8PEFmiDqiV6YDcqQB3eIKdmUlwe2wNapZ2Uh9KoJLdFj@CoElIZxvrTJ1iFxfSJB92ALoNdYy4y7ovdSmSkvXnlhEMnXytgBn2w@ZA/z6OEFWB1knVKMeUR3kqQBnmqmZMIdtVXg4EqwTyZLNqmfSV5FJrcA5qgUn9RRHo1MhuXlpn0aKEnZb/0kDDLFc4PWgyiEdxhs54fBUgdzwdP…

Neil

@cairdcoinheringaahing Charcoal, 3 bytes: ＩＬα

user56656

8:58 PM

@H.PWiz Here:

https://tio.run/##hVVta9swEP7uX6EZRiR2NkvzrVsLzmB0kNEy94NLElxvURqDIxtbTTay/vbszrLrl7gZAUd67nnuRbqzszxN0ien2MfHY6TTLZ/f/L1fCuY412x@s4TDr3QlQ/0nk/wGoiTbROIFSuK9cK1K8R@@a1n7wjCWbr3kNrM/2QttC9gXyFCp5oHxYzs2YlDoSMutVDpEAzLiNQ/gwVA6NiLbznVf9ICi92@IHozo83Ck1r6sMBDGQbVx2wSTt7Gbdcdcxa8K42W4CiszEHaHHnSIp1USveF3vXc8t7zWTgccorOf0SpsqPP6KvGiepag6YsA7zlYXI0/vkCXRD1hJcW4DnkIrjAlj/IKwRPYOu2sXKRedKk1ewpfhIAamJZLj7ABF5MTF3QPngD6mxo306HoVi4LHabrMImVfK2MHfDJFlfscaEeX4C1Se6pxF4oupMsj/FUCy0z7uutBh9Xgl06LNvkUSF5E5nMApivc3xSR4U0MgWWV0L7PNaSst9GWRIXmpeA8QcqgXcYbBcl8coECyA0xZtTB0oHDq1sAmDzEZv549GSJnFYenFWenFOOjkrnQx…

That should fix it.

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