The Nineteenth Byte

Ørjan Johansen

06:00

.oO ( Do we hear 10, anyone? )

Pavel

@user202729 haven't used it in 2018 yet

Pretty much everything that you might use yes for provides a flag to automatically accept everything.

Οurous

06:29

@Pavel I didn't know that was a thing. It seems to just print an infinite number of ys.

How is that ever useful

It can't be that hard to press y.

Just put a ballbearing on the key

user202729

Hold, not press.

It can be useful if you're not around.

(e.g., download for 10 hours before prompting for install)

Οurous

(ballbearing on key holds it)

user202729

lookup dictionary

Put... why this? I think this is a mechanical part used to remove sliding friction?

Potato44

06:52

@user202729 Its a dialect thing, they are referring to a small steel ball, about 1cm in diameter.

Ørjan Johansen

@Οurous Won't work, because you have to press the return key in between. I think you need two of those dippy bird things.

user202729

Finally I could get the (Hexagony) colorer to work on Linux. But it seems buggy. Does anyone know of a fix?

Jo King

07:49

@user202729 Oh wow, I didn't notice. Well done, the bounty will be heading your way soon!

Jo King

08:10

(I haven't awarded a bounty before, do I do two 500 point bounties to award 1000?)

label a -- goto a

08:47

reeeee on my history exam there wasn't the question for date of byzantine fall, this is sad, we wasted half an hour discussing 1453

@EriktheOutgolfer

New Main Posts

0

Q: Generate speech from text using only Web Audio API

Input: hello universe (plain text, english language) Requirement: Synthesize input text to speech as audio output to speakers using Web Audio API for waveform generation. Rules: Use only Web Audio and APIs implemented by the browser (excluding web service requests to meet requirement)....

betseg

If a question on code review gets no answers does that mean the code is perfect?

mınxomaτ

@Dennis Tips: I recommend TinyScanner for Android to quickly "scan" paper notes into the rM store. Also I've setup rsync on the device to sync to my Google Drive, too. You need to demangle the UUID file names though (but there's a script for that in the wiki). The on-device software does have some rough edges, let's hope for continued updates.

Jo King

09:03

@betseg I've posted a brainfuck program to code review that got no answers, does that count?

betseg

Probably

Martin Ender

@JoKing yes

Jo King

(I then golfed 73 bytes off it, so probably not)

Martin Ender

I'd probably leave one of the two bounties up for the full 7 days (to draw attention to the answer) but then award the other one as soon as possible (after 1 day, I think), so that you don't hog the challenge for too long with bounties.

Jo King

That was the plan. I should probably set an alarm or something to make sure I remember to award the bounty

uhh, is there any way to edit the bounty message? My link didn't go through

Martin Ender

09:16

you'll get a notification 3 days before the end, 1 day before the end, and when it ends (and then you still have 24 hours to award it)

no there isn't, but I can refund the bounty

Jo King

Yes please

Martin Ender

try again

bounty message markdown is the same reduced markdown as that for comments

Jo King

Thanks!

Martin Ender

(so no paragraphs or stuff like that)

Jo King

Okay, got it this time

Neil

09:37

@Dennis I've seen that bug with the MS Java for IE JIT - I have a Java applet that works perfectly well in other Java implementations, but if you throw MS's JIT at it then it throws an impossible exception, unless e.g. you put a print statement in.

orlp

10:32

dwitter.net/d/5747

Neil

tfw you reply to a comment only to find it's since been deleted

Martin Ender

sorry ¯\_(ツ)_/¯

betseg

11:20

If I comment on an old post will it appear on the main page

Martin Ender

no

only edits, answers and bounties do that

ASCII-only

yay successful-plain.glitch.me/index.html random project kinda works now

Adám

@ASCII-only What's the syntax?

ASCII-only

@Adám and is &, up arrow thing or . (or nothing at all), or is |, down arrow thing or +

also not very much is implemented atm

Adám

@ASCII-only How about not? Can I use parens? What are the variables?

ASCII-only

11:27

@Adám not is ~ or !, haven't tested parens, any letter is a valid variable

Adám

@ASCII-only What's the order of evaluation then?

ASCII-only

@Adám order?

Adám

@ASCII-only As in precedence order and RTL/LTR.

ASCII-only

LTR, precedence is not, and, or (this is convention right?)

caird coinheringaahing

I am waaay too late for this, but congrats to @Mego and @DJMcMayhem!

Οurous

11:32

@ASCII-only enters a & b -> TypeError: Cannot read property 'data' of undefined

ASCII-only

@Οurous yeah >_> it's really unfinished atm (as in it can't fully simplify yet), there's like a million bugs

because i never tested it

Adám

@ASCII-only p&~q|p&q → TypeError: steps[(steps.length - 1)] is undefined while I expected p.

Zgarb

@ASCII-only a&~a|~a gives 1...

ASCII-only

:/ oops

Zgarb

In fact 0|~a gives 1 too.

1&~a gives 0. :P

ASCII-only

11:40

:/ yeah hang on i know where the problem is

ASCII-only

11:52

ugh finally fixed (well, kinda)

Adám

@ASCII-only p&~q|p&q → ReferenceError: parseBooleanExpression is not defined

xfix

Rust is so verbose, in meantime Java 10 will noticeably make code golf programs shorter

what a world this is

ASCII-only

@xfix Java 10 has what

xfix

var

type inference, to be exact

ASCII-only

@xfix finally

it's slowly catching up to C#

xfix

11:58

i mean, it's still Java, but at least it will be a bit shorter

ASCII-only

@Adám what should that evaluate to

Zgarb

@ASCII-only ~(a&~a) gives ~0.

In fact ~0 gives ~0.

SEJPM

@ASCII-only even C++ had type inference for a while now (for 7 years to be precise)

xfix

to think C++ was supposed to have auto all along, but people complained about changing meaning of auto long time ago

so the feature was removed

ASCII-only

@Zgarb Fixed

xfix

12:02

like Cfront had auto working in 1984

everything new is old, just disappeared for some reason, sum types were in so many languages back in a day, but today, well...

SEJPM

@xfix sum types?

xfix

also known as tagged unions

SEJPM

@xfix well, it appears they are making a comeback in modern low level languages

eg Rust has them

a HDL called "BSV" has them

Haskell has them

xfix

to be exact, tagged unions were in ALGOL 68, Pascal, Ada, Modula-2, and it took a while for it to return since then in non-functional programming languages

also C++17 adds sum types

i guess Cyclone had tagged unions since then, but is that really enough?

betseg

@xfix I thought your avatar was π⁰, as in the meson :D

xfix

12:14

honestly i don't even remember why i picked this avatar, but too lazy to change it

and it is somewhat cryptic, so whatever

Adám

@ASCII-only p

xfix

Cyclone itself is more of a research language, so i'm not sure if it counts for tagged unions (most of it appeared in Rust however, including borrow checking)

user202729

12:42

C++ auto has another meaning.

betseg

i.sstatic.net/2mMca.png hm

SEJPM

@user202729 C++ is also used for structured binding

ie auto [ a, b ] = potatoMap.insert("potato",42);

or for(auto[k,v] : potatoMap)

user202729

That's new in C++17?

SEJPM

@user202729 yes

C++17

C++17 (or, informally, C++1z) is the name for the most recent revision of the ISO/IEC 14882 standard for the C++ programming language. The C++17 specification reached the Draft International Standard (DIS) stage in March 2017. This DIS was unanimously approved, with only editorial comments, and the final standard was published in December 2017. == New features == C++17 introduces many new features. The following lists may not be complete. === Language === Making the text message for static_assert optional Removal of trigraphs Allow typename (as an alternative to class) in a template tem...

^ this is an overview, there are various blogs out there with other (less complete?) overviews, but more explanation per-feature and of course there is cppreference

moonheart08

12:59

cppreference is best reference :P

user202729

What do you get from running this code?

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace N {
	public class T : Form {
		protected override void OnPaint(PaintEventArgs e) {
			Graphics g = e.Graphics;
			g.Clear(Color.White);

			var arrowPath = new GraphicsPath();
			var arrowPen = new Pen(
				new SolidBrush(Color.FromArgb(64, Color.Gray)), 17.5f);

			arrowPath.AddLine(new PointF(50, 50), new PointF(90, 90));

			var startCapPath = new GraphicsPath();
			startCapPath.AddPolygon(new[] {

moonheart08

Triangle

user202729

Screenshot please?

moonheart08

wait

oh, there's more to it lol

i'm just reading it

the new PointF declarations give out a lot of info

user202729

Just run it.

I'm on Linux and it gives

moonheart08

13:10

Too lazy to figure out how. I'm on Linux too

HyperNeutrino

do any of you know how to tunnel a localhost port to a static IP (other than ngrok)?

user202729

Anyone on Windows can check? I don't want to reboot my computer.

moonheart08

well, looks like the intention i- oh.

Emigna

I get the same form on windows, though the colors blend

user202729

... wait a minute.

I think I made a mistake. Nevermind.

Basically I am fixing an unexpected behavior with HexagonyColorer, and I'm trying to create a MCVE.

HyperNeutrino

13:18

7 mins ago, by HyperNeutrino

do any of you know how to tunnel a localhost port to a static IP (other than ngrok)?

user202729

That is, you want to do what ngrok does without actually using ngrok?

HyperNeutrino

basically yes

(I need to avoid the school board blocking ngrok)

also is there a way to find the IP of the destination of an ngrok tunnel

Anonymous

@HyperNeutrino We're not going to help you bypass your school's filters

HyperNeutrino

@Mego I just need to host my server and have it available at school (it's the contest grader I was working on yesterday). I'm not doing anything illegal :P

user202729

It seems that ngrok is open source

so you can just download everything?

HyperNeutrino

13:21

or really just do any of you know how to find the IP of the destination. that would probably be fine

(I kind of doubt that's possible because that sounds like a security flaw)

Anonymous

Ok so if you want to do this for completely legal reasons: set up a pair of sending and receiving sockets between your local computer and the remote computer, and communicate over those

Anonymous

Or, if you're working in a high-level environment like Python, use something like Celery

HyperNeutrino

hm ok. I'm hosting the server using flask in a docker container so I could try that

Anonymous

Get request from local machine -> send Celery task to remote server -> remote Celery server forwards request to Flask, and sends back the response

HyperNeutrino

also, if I host a flask server on :5000 and then go to 192.168.my.ip:5000 on another computer, it doesn't connect; is there any way to make that work? or am I using the wrong IP from ifconfig?

Anonymous

13:28

Make sure that the server is listening on 192.168.foo.bar (or 0.0.0.0), and that :5000 is open in your firewall

HyperNeutrino

I'm running it with host="0.0.0.0", port=5000 and it works when i go to the IP from the same computer but I'll check the firewall; i doubt it's closed though

oh well. i'll try to figure it out when i get home because basically everything is blocked

Anonymous

If your local computer isn't on the same network as the remote one, 192.168.foo.bar won't work. Use curl ipinfo.io/ip on your remote machine to get the public IP.

HyperNeutrino

oh okay, thanks. BTW local computer = server and remote computer = client?

Anonymous

I was meaning the other way

Anonymous

Remote computer = server

HyperNeutrino

13:37

oh that makes more sense. okay thanks!

Adám

13:50

Yay, works:
https://tio.run/##hVXPaxtHFL7rr5jbWEVGVnppvZhg0kAMpYa2kEDoYbQ7K0@9O7PamY0lTHXIIZGN1xRKj4WSpFTxJYSQHgwlkD9l/hHnvdmxpJXW9l602nnve9/73o9hWbIZjVmiBldXdvoyEjqzL37/Xg1ESPgoy4NnLNeBYf2EB/b8z739wOQFDyTnEY8CISMdsCQJtEgzsAiZ5rpFnCHAbJGbHlv@RbY2@2AeEQDhIyEHLYKxwA3j2ulbW84AaLfzTe9be/Yfvtb9@cjkLDToJZAfkSz10X96tPvd/mNbXiBic/REhSwRmhNzwNMWgSQg8j17@o8tX39@17Plh3tf2ZNXawDoC8aboUr7ijhhKuLHtjy35WWHAo4tP9LfPs/siz/AdM1bazGQhLPwgAijSabgQ18kRiB7J6GDOEcdbtCOP2NJwQxHKsSrvr0Xk60dO5113YdGPxE78jFLNNDGx1cctKIPlARFIxEaoSQldIvO/YaFMMA4T8YQ5yE4Qyw7/bcx0lIc7JW1MD@zwihouDGE6NGa21qYWxsoFSNon5zrIjG6CoMBIYyj1V3R/to…

Neil

ugh, accidentally updated to Firefox ~~ugly Chrome lookalike~~ Quantum

Adám

@Neil ---words---

Neil

ta

Adám

@Neil Funny thing is that Chrome was called so to jab at the excessive chrome of other browsers, but now FFQ has less chrome than Chrome.

Neil

yeah, well I like my chrome

J. Sallé

13:57

@Neil FFQ looks nothing like chrome though

Neil

well they changed their hamburger menu

Erik the Outgolfer

@Neil you were always supposed to...

J. Sallé

@Adám I can't even

Why is it taking a bazillion variables but actually only taking one (expr)?

Neil

@EriktheOutgolfer I thought I had the setting for "I still want to use my ~~legacy~~ decent extensions for a bit more kthxbye" turned on

Adám

@J.Sallé The ; separated list declares local variables.

NieDzejkob

14:01

@totallyhuman I believe I've fixed it now

J. Sallé

@Adám Oh, I see. Are they needed though? I thought I could just declare them inside the function, but I might be confusing myself?

Also, what does the ; inside square brackets?

HyperNeutrino

found a better solution to having ngrok blocked: get school admin to contact IT to unblock my tunnel xD hopefully that works

Erik the Outgolfer

@J.Sallé that's for multi-dimensional arrays; the ;s separate the dimensions you're indexing into

J. Sallé

@EriktheOutgolfer Ah, I hadn't noticed that was a multi-dimensional array

Dennis

14:28

Re: asciinema.org/a/b779uumH8eHu7M3JR6Eq5tT9N, does macOS still come with Bash 3.2?

Poke

@HyperNeutrino when i was in school one of my buddies wrote a web proxy that he got unblocked since he used his website for "educational purposes"

aka flash games

Erik the Outgolfer

@Dennis that just added another reason for me to not buy anything from Apple

Dennis

14:41

I'm sure there's a way to update it, but seriously, Bash 4 was released in 2009!

New Meta Posts

0

Q: Should we repost the Kolakoski challenge?

We've got a fairly old challenge about the Kolakoski sequence. Unfortunately, the challenge is fairly restrictive in its I/O requirements: in particular, input has to be taken via command-line argument. This prevents most esolangs from competing entirely, which I think is a shame for such a popul...

discussion specific-question reposting

New Main Posts

2

Q: The weight of a Zero

Given an ordered list of numbers (possibly with leading zeros), arrange the numbers vertically, then let all zeros drop all the way to the bottom and all overhangs drop to the bottom-most open slot. Worked Example Say we were given the following as input: ['0000312941295', '239124000124581598'...

code-golf array-manipulation

Poke

speaking of apple... bloomberg.com/news/articles/2018-02-21/…

so i guess phone prices will start going up?

start investing in cobalt maybe

J. Sallé

@Poke why would they go up though? They're buying large quantities of raw material directly from the source, shouldn't that make their phones cheaper?

Or you're talking specifically about the shortage?

Poke

14:58

talking about the shortage

also the fact that if apple is buying more, that leaves less for other battery manufacturers

J. Sallé

Indeed. I was thinking of iPhones only since that's what I use :p

user202729

Someone changed their avatar.

Erik the Outgolfer

uh, is that bad or something

J. Sallé

People do that often enough

user202729

@NewMetaPosts Yes and close as dupe. (too short to post as an answer)

Actually only WheatWizard do that often.

NieDzejkob

15:15

@user202729 Not too short if you ask me

user202729

I mean, there should be explanation/etc. in an answer.

... there is no low quality queue on meta.

NieDzejkob

15:33

the question contains arguments itself...

user202729

15:44

Ok, so I have this C# program:

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace N {
	public class T : Form {
		protected override void OnPaint(PaintEventArgs e) {
			Graphics g = e.Graphics;
			g.Clear(Color.White);

			var arrowPath = new GraphicsPath();
			var arrowPen = new Pen(
				new SolidBrush(Color.FromArgb(64, Color.Gray)), 17.5f);

			arrowPath.AddLine(new PointF(50, 50), new PointF(90, 90));

			var startCapPath = new GraphicsPath();
			startCapPath.AddPolygon(new[] {

What do you get when running it?

NieDzejkob

@user202729 Just a guess, but running it might get you the answer

Pavel

@user202729 Oof. Windows.Forms is like the one thing .NET Core doesn't do

user202729

I know. But I am getting 2 different output on Windows and Linux.

Pavel

@user202729 ^

user202729

That's what I get on Linux. On Windows the ends fit well with the path (i.e., the WidthScale = 1/3f works)

Pavel

15:50

I recently discovered a program called exa. It's like ls, but better and more colorful.

user202729

But needs installation.

Basically "ls replacement".

Pavel

@user202729 That's exactly it. I've aliased ls to exa.

@user202729 Mac has a brew package, Arch and Fedora have it in their repos.

Poke

i have terminal colors set up

what does exa do for me

NieDzejkob

exactly, same question

Pavel

16:09

@Poke Look nicer than ls, show git status, show human-readable file sized by default, have option for tree view.

xfix

but how am i going to see if 6K is bigger than 5M?

Pavel

@xfix Because K is less than M?

xfix

it's not obvious by length when using ls -l

nah, it's just a workflow sort of thing, i suppose

Pavel

@xfix Or -B

New Main Posts

3

Q: Remove duplicates from a String

Inspired by this unassuming StackOverflow question. The idea is simple; given a String and an array of Strings, remove any instances of words in the array (ignoring case) from the input String other than the first, along with any additional whitespace this may leave. The words must match entire ...

code-golf string

user202729

16:19

I thought we already had something like this?

Poke

@Pavel why would i want git status when listing the files in a directory? haha

tree view could be nice i guess

file sizes can be attained in ls with the -l flag o.O

Pavel

@Poke It's not obnoxious or anything. It's just a one or two character indicator for changed/added

And you need to supply the --git flag, so I have alias ls=exa --git -h

Poke

/me shrugs

to each his own

xfix

i don't know, the text editor i use already shows which files were modified

user202729

Ok. I'm not sure if it's a mono bug or...

xfix

16:24

and the prompt is configured to show whether anything was modified

in my case, why would i want git status information?

user202729

Can anyone run HexagonyColorer on Linux?

Pavel

@user202729 Probably

GTK# is.. interesting.

H.PWiz

@orlp Here is a gf for P(x=r). I believe it's correct

NieDzejkob

@user202729 I tried many times, couldn't do it

user202729

As a temporary solution I would just remove the caps.

NieDzejkob

16:38

ended up doing a hackjob in GIMP

@user202729 I'm not sure I understand

user202729

At least I could get it run but there are some bugs.

@NieDzejkob CustomLineCap is used for line caps of arrows. That doesn't work well on Linux.

@NieDzejkob Which errors do you get?

Ok, now I removed the caps.

Now it looks like this.

New Main Posts

3

Q: Code Golf: Your own horizontal pet ASCII snake

Very heavily inspired by this challenge Code Golf: Your own pet ASCII snake - I thought making it horizontal would add an extra layer of complexity. An example horizontal snake: 0 0 0 0 0 000 00 0 00 000 0 0 000 0 0 0...

code-golf ascii-art random

quartata

16:59

The provided interpreter on esolangs does not build correctly. — quartata 20 secs ago

@cairdcoinheringaahing is this answer invalid?

I suspect it would be a trivial fix but

NieDzejkob

Are you talking about this? You know, there's also a binary provided...

quartata

didn't see that, kind of a nuisance it's Windows-only then

not sure how they could have possibly built it either

moonheart08

Remembering how C++ templates worked after several months of rust will be ~~painful~~ fun

Pavel

@quartata Maybe the executable is outdated?

And like the last commit broke it

Hmm, I wonder if I should check out Rust

dylnan

@Dennis and Jelly users have you tried cracking this M submission for the redacted primality challenge? I believe it is safe now but I kind of want someone to crack it.

orlp

17:30

@H.PWiz I believe that was already posted on the source question

but it's now deleted

Pavel

> If most people turn into muderers all of a sudden, we'll need to push out a firmware update or something.

From today's xkcd

caird coinheringaahing

@quartata Hmm, does the .exe file work?

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Find Graph Isomorphism Inspired by this puzzle graph-theoryfastest-algorithm Given two isomorphic directed (unweighted) graphs with labelled nodes, find an isomorphism between the two graphs. Details The graphs can be represented as an adjecency matrix, as set of pairs that represent edges, ...

Dennis

17:51

@dylnan Just a sec.

H.PWiz

@orlp Oh, I don't see deleted answers on Math

orlp

@H.PWiz me neither

moonheart08

x86_64 has two things:
Large (4+ byte) instructions
Strange ones.

I just found a strange one.
da5: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1)

Why would you need to waste all that space O_o

H.PWiz

@orlp For what it's worth, it comes directly from your comment on the question

HyperNeutrino

made a terminal-based minesweeper game here idea completely stolen from @betseg :P (BTW I made my own version for the sole reason that I find typing in the coordinates a bit tricky and I think using arrow keys is nicer)

moonheart08

18:00

Ok, this is an actual oddity i found in code made by LLVM. wtf?
d51: 66 66 66 66 66 66 2e data16 data16 data16 data16 data16 nopw %cs:0x0(%rax,%rax,1)
d58: 0f 1f 84 00 00 00 00
d5f: 00

it's a large block of data followed by a nop, said data is directly in the execution path

betseg

@HyperNeutrino ooh nice

but how do i flag

orlp

@moonheart08 doesn't mean it gets executed

might get jumped over

and used as local data that's hot in the cache

betseg

press F, solved it

HyperNeutrino

@betseg ty :D also, f. I'll add help code later

o you figured it out :P yay

orlp

@moonheart08 but now I gotta eat so can't talk brb later

HyperNeutrino

18:03

q to quit, f to flag, <space> to step, arrow keys to move cursor

anyway gtg o/

betseg

i was just typing a message :/

moonheart08

@orlp This is the code that precedes it:
d3d: 4c 8d 74 24 18 lea 0x18(%rsp),%r14
d42: 4c 8d 7c 24 10 lea 0x10(%rsp),%r15
d47: 4c 8d 64 24 20 lea 0x20(%rsp),%r12
d4c: 4c 8d 6c 24 08 lea 0x8(%rsp),%r13

HyperNeutrino

@Poke I mean coolmath-games.com is unblocked on my school wifi ¯\_(ツ)_/¯

moonheart08

Wait

betseg

@HyperNeutrino oh no, it doesnt expand to the cells surrounding a cell if it has enough cells around

moonheart08

18:05

Huh.

d2d: 85 c0 test %eax,%eax
d2f: 0f 8e b2 00 00 00 jle de7 <_Z15print_backtracev+0x107>

HyperNeutrino

@betseg wdym by that?

moonheart08

That itself might be data?

compilers at -O3 are magic

betseg

before i.sstatic.net/HlFbZ.png

press space

HyperNeutrino

sry imgur is blocked

betseg

after i.sstatic.net/ACnY0.png

HyperNeutrino

18:06

but brb

betseg

i.hizliresim.com/1JE3l1.png before i.hizliresim.com/LbDXWJ.png after

Mr. Xcoder

Yay I finally got to use untruthy in jelly :)

betseg

^^ turkish imgur

Pavel

@betseg Blocked here too actually

Although, imgur is, but stack.imgur isn't

betseg

you mean imgur is blocked or hizliresim?

Adám

18:09

Announcement: APL Cultivation in 20 minutes.

Kevin Cruijssen

I'm fairly inexperienced with Retina, so could someone explain how I can have multiple different inputs? To be more concrete: I need two inputs: a sentence and a list of words. How can I loop over the words and use them in a match-regex of the sentence (input format is flexible)?

HyperNeutrino

@betseg that's after pressing space?

sry gtg class now

betseg

@HyperNeutrino that is the thing i want to have and my program implements it

and ms minesweeper, gnome mines etc have it too

Kevin Cruijssen

Nvm my comment above, I figured it out :)

orlp

18:36

@moonheart08 what's the piece of code you're inspecting?

label a -- goto a

18:52

heh, dupe of Mr.Xcoder's chat question, but what would be a good name for a class-importing/loading function? import, load, use, include? Something else?

Pavel

Node and Ruby have require. C# uses using. Appleseed uses load.

I'm a fan of import though.

moonheart08

@orlp -O3 ified (by clang++) code that gathers and prints a backtrace of the callstack

Uses the libunwind library

gist.github.com/moonheart08/733415ae14eb1d4cc1079ab3b51c293f

label a -- goto a

For me, both import and use sound good in the situation, maybe I'll add both as synonyms. That would be better for golfing, on the side. ¯\_(ツ)_/¯ Even if the language is definitely not good for golfing.

It requires at least 2 files for working script

New Main Posts

19:11

1

Q: Collapse the antistring

In this challenge you will be given an alphabetic string as input. We will define the "anti-string" of a given output to be the string with the case of all the letters inverted. For example AaBbbUy -> aAbBBuY You should write a program that takes a string as input and searches for the longes...

code-golf string

HyperNeutrino

19:38

@betseg so basically if you space-bar a satisfied node it will reveal all nodes around it

betseg

yes

HyperNeutrino

hm ok...

should it care about whether or not the flagged mines are correct, or just if there are enough flags around it?

betseg

the latter, if the flags are in the wrong place game should fail

moonheart08

19:51

Is there a way to force clang to treat a function as a 'black box' and not do compiletime evaluation on it?

moonheart08

20:01

Wait, oh, i remember. It's done using a asm("") statement

oh, clang

it outsmarted me (again)

Looks like that doesn't work

Dennis

Compile the function separately and provide only a prototype for the calling program.

moonheart08

Kinda hard. i'm trying to see how it compiles when inlined

Dennis

Ah, OK.

moonheart08

So it's best if i can find a way to do it with minimal/no effects to the result

label a -- goto a

20:22

What prefixes can be good for numbers? I mean ex. 0x, 0b. I would like to have a prefix for base 16, 8 and 2

:/

16 is 0x, 2 is 0b, but what would be good for 8?

moonheart08

Managed to make it do it

Just had to write an identity function (mov %1, %0) in ASM

Pretty optimal SIMD code, so thats nice.

Altho, i have no idea what the hell it's doing right here.
cca: f2 0f 58 05 46 02 00 addsd 0x246(%rip),%xmm0 # f18 <_IO_stdin_used+0x8>

Neil

@labela--gotoa ES uses 0o

quartata

@moonheart08 is this before a call?

moonheart08

Nope, it's before a math function

cca: f2 0f 58 05 46 02 00 addsd 0x246(%rip),%xmm0 # f18 <_IO_stdin_used+0x8>
cd1: 00
cd2: f2 0f 2c c0 cvttsd2si %xmm0,%eax
cd6: 0f 57 c0 xorps %xmm0,%xmm0
cd9: f2 0f 2a c0 cvtsi2sd %eax,%xmm0

quartata

I mean the weird nop

moonheart08

20:29

oh that, i forget.

quartata

What version of LLVM are you using?

(+ what architecture)

moonheart08

LLVM 5.0.1 x86_64

label a -- goto a

@Neil Also thought about it, well if you mentioned it, that might not be a bad idea :p

moonheart08

target is unknown-linux-gnu

host CPU is 'bdver4' according to the llvm version output.

oh

that's the AMD model

quartata

It might be a retpoline

moonheart08

20:35

maybe.

i mean, this is inline code, so it's in the main function, so i don't know if a retpoline makes sense in that context

Οurous

Assembly is alien to me. You're all wizards.

moonheart08

lol

I know only part of x86. x86 in its entireity takes a sorcerer to understand.

Pavel

I sorta get .NET assembly

Οurous

I get Cleans ABC, but that was out of necessity.

moonheart08

maybe even a demigod is necessary... Yea that makes sense. Any being lesser than a demigod is incapable of understanding the entireity of x86_64

5

@quartata probably not a retpoline. the -mno-retpoline option and the -mretpoline option don't exist

Pavel

20:40

iirc Dennis know x86_64 pretty well

Dennis

Well is an overstatement.

I do think x86_64 is a lot easier to grok than many of the languages commonly used on PPCG though.

betseg

i.sstatic.net/WSLyc.png nice

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