The Nineteenth Byte

quartata

19:01

But surely your parents are concerned too. This isn't just internet censorship

Gabriel Benamy

19:23

i love javascript. undefined == null is true, undefined === null is false. NaN == NaN is also false.

Rainbolt

Don't bother comparing to null. Just if (myVar) {} and avoid the whole situation

Gabriel Benamy

@Rainbolt I'm not doing anything like that, I'm just laughing at how absurd the whole thing is.

Dennis

My favorite:

> "\t" == 0
< true

Gabriel Benamy

what

Rainbolt

It took me over a year to realize that if I declare something without var, it continues up the stack until it finds a variable with the name. Once it reaches global, if it still hasn't found a variable with that name, it just declares it there (in global).

Gabriel Benamy

19:27

what

@Dennis ?????????????????????????????????????

@Dennis "\n" == 0 is also true

as are \r and ` ` (empty space)

Dennis

Yes, it works with any combination of whitespace characters.

Gabriel Benamy

who... who designed this...

Rainbolt

Keep in mind that Dennis is demonstrating how to use the wrong operator, so of course it will do silly things

Use === to get the behavior you expect

Dennis

All JavaScript operators are the wrong operator.

3

Rainbolt

Oh no, I better write some bugs then. I'm using the wrong operator everywhere!

Dennis

19:33

And of course, there's the lack of transitivity.

> "\t\r\n \v\f" == 0
< true
> 0 == "0"
< true
> "\t\r\n \v\f" == "0"
< false

Gabriel Benamy

i'm crying

Dennis

Of course, JavaScript isn't alone in its madness. tio.run/nexus/…

New Meta Posts

0

Q: Help the Help Center

When I read through the help center recently, I was surprised how little some of the pages were related to this site, one example being How to not be a spammer, which looks like it comes from Stack Overflow with only the site name changed. Is it possible to change big parts of the help center, as...

feature-request

0

Q: Do we not need [knot-theory]?

A recent challenge (A Rather Knotty Conundrum) added the knot-theory tag. No previous knot theory challenges use this tag yet. Before I consider using the tag, I want to see if the tag is really necessary. This tag might make sense on Math.SE, but it seems pretty specific for our use on PPCG, and...

discussion tags

Dennis

@Dennis Not sure if that's better or worse.

Gabriel Benamy

19:49

cause of death: @Dennis

Dennis

Sure, blame me, not the people who made those insane design decisions. :P

TimmyD

Why are whitespace strings falsey?

That's horrible.

<some giant Whitespace program> == 0

Hehe, I made my avatar big enough that it covers up my name.

Dennis

Oh, they're not falsy. They're just equal to false.

> "\t\r\n \v\f" == false
< true
> if ("\t\r\n \v\f") console.log("truthy")
  truthy

TimmyD

twitch

Dennis

Because that totally makes sense.

TimmyD

19:57

How does the Internet not fall apart with such a language as one of its main components?!

mbomb007

I love these hats. I can make such weird things with my Kirby avatar!

Dennis

No clue. The mind-boggling inconsistencies between implementations makes it even worse. The same CSS animation has four different behaviors in Chrome, Firefox, Edge, and IE 11. And I can't even tell which one got it right. None of them makes any sense.

mbomb007

I give thee, Kirby wearing a black dress with a wildly fantastic hair-doo

TimmyD

@mbomb007 Kirby has gone super-saiyan?

mbomb007

:D

I've changed my avatar 4 or 5 times today, I should take a screenshot to keep it.

It's worth it.

TimmyD

20:03

@Dennis That's ... wow.

Gabriel Benamy

@Dennis Why must you desecrate my corpse like this? I'm already dead, and yet you continue

TimmyD

@GabrielBenamy Oh, PowerShell is better (in some ways). An empty script block is truthy, but an executed empty script block is falsey.

PS C:\Tools\Scripts\golfing> if(&{}){"true"}

PS C:\Tools\Scripts\golfing> if({}){"true"}
true

Gabriel Benamy

@TimmyD what happens if you try to execute the output from the falsy version

mbomb007

9

It looked good right-side-up, but I couldn't resist using the mustache as eyebrows.

TimmyD

@GabrielBenamy Executing empty results in nothing

Conor O'Brien

20:09

@Downgoat do you have much experience with the HTML canvas?

flawr

@Dennis O_O what happened to your face?

Conor O'Brien

@GabrielBenamy if you wanted an explanation, since there is a numeric argument, == tries to cast both of its arguments to numbers. Leading whitespace in a number cast is treated as a no op, and so the cast returns the default value, 0. So, the statement is equivalent to +' ' == +0, or 0 == 0. It's perhaps unusual, yes, but not insane. There is a method to the madness.

Gabriel Benamy

@ConorO'Brien " a" == " b" yields false for me

Conor O'Brien

@GabrielBenamy right, because neither of the operands are numbers.

TimmyD

Empty arrays in PowerShell are falsey. However, empty hashtables are truthy.

New Main Posts

20:20

0

Q: Number of prime knots with n crossings

A prime knot is: a non-trivial knot which cannot be written as the knot sum of two non-trivial knots. Here are all prime knots with 7 or fewer crossings (the Unknot is not prime): You need to output the number of unique prime knots for a given number of crossings. 1 0 2 0 3 1 4 ...

code-golf sequence knot-theory

quartata

@ConorO'Brien Did you see my question?

Conor O'Brien

@quartata eh? which question?

quartata

Check your pings :P

Conor O'Brien

oh the one with the local scope thingy

quartata

Can't link it on mobile but basically

When I say locals I don't mean let or anything

Conor O'Brien

20:33

then what do you mean?

quartata

just variables in the function scope

That's local in ES5

When you define something outside a function it goes in window hence why I suspect there's an equivalent

Conor O'Brien

there is no equivalent to window

quartata

That's block scope

try (function() { ... })()

Conor O'Brien

so basically you want this to work:

(function(){ var k = 3; console.log(locals.k) })(); window.k

quartata

Yes

Downgoat

20:40

@ConorO'Brien unfortunately yes

quartata

?

Downgoat

@quartata you mean like this?

quartata

I want the equivalent of locals() in Python

Downgoat

I dunno what that does

quartata

I want every variable defined in this function/namespace

Gabriel Benamy

20:43

I just explained to my boss (a programmer) the concept of truthiness

quartata

Failing that how can I force a variable to be global? I could save a copy of window and take the difference

TimmyD

@GabrielBenamy Did you use JavaScript?

quartata

which would be slow as molasses but usable as a fallback

In case this is an XY problem I'm trying to transpile generators. My plan was to place labels at each yield, save the variables then reinstantiate them and jump to the appropriate label when called again

I'd rather use a web worker but they may not be available

@Downgoat @ConorO'Brien

Conor O'Brien

@Downgoat how do I scale a range? e.g. take the imagedata from (x1 y1) to (x2 y2) and make it larger?

Gabriel Benamy

@TimmyD My boss thinks JS is wizardry. I showed him using PHP (the language he writes most of his code in)

TimmyD

20:50

Well, from what I've just seen in this chat, JS is wizardry.

As in, it requires a wizard with a Scroll of Comprehend Language to be able to understand it.

quartata

@TimmyD That's mostly because I'm trying to fit a Pytek shaped peg in a JS shaped hole

Gabriel Benamy

I explained to my boss the concept of the null coalescing operator, which is ?? in PHP 7

and how it saves you from a ton of unnecessary if isset / elseif isset / else statements

and how you can chain ?? operators to each other. "Wait, that works?" "Yeah, because of this is true, it short-circuits and evaluates it, otherwise it tries the next one, and if that's true it short-circuits and evaluates, otherwise it tries the next one"

"Anything that evaluates to something tangible is true, otherwise it's false" "yeah but it's not the same as false, right?" [codes up a direct example] "wow, I didn't know that"

VisualMelon

(I've snapped my long meta post into Question and Answer for those who might be interested)

ATaco

With credit sometimes you just don't learn things about programming until well after you're a professional, even basic concepts.

TimmyD

@quartata See, if I ever get around to finishing my sandbox entry, then you'll immediately be able to tell these things without straining yourself. ;-)

ATaco

20:58

i find the best programmers were never hand held by tutorials

TimmyD

lolol ... On an email chain at work, we're discussing a particular technical point regarding email domain names. Here's the funny snippet:

> Before his future was freed up, a former fellow employee unwittingly ran a script that changed virtually everybody’s email address.

ATaco

The dev team at my work uses Unicode and UTF-8 interchangeably

New Main Posts

1

Q: Find largest product of longest subsequence between min and max

Task: Input: A non-empty sequence of integers greater than zero, the length of which is greater than 1. Output: The product of all elements of the longest subsequence between the minimum and maximum elements of sequence including themselves. Note: Because the minimum and maximum elements ca...

code-golf sequence

flawr

@GabrielBenamy TIL, but on the other hand I don't remember when I used PHP the last time

ATaco

but they seem to have no idea that ASCIIis in the UTF-8 encoding

DJMcMayhem

21:01

@ATaco I don't think you understand the difference between Unicode and utf-8

Utf-8 just maps byte sequences to Unicode code points

ATaco

>please remove any Unicode from filenames

DJMcMayhem

In other words, utf-8 is an implementation of Unicode

Conor O'Brien

@quartata as in, JS generators?

ATaco

utf-8 is one of many encodings that support Unicode, which itself is a 16bit encoding that encode almost every character, including emoji

if you remove Unicode from a file name, which is stored in 1252 anyway, would be to remove the file name

implicitly stored in 1252, I should say

quartata

@ConorO'Brien ?

Downgoat

21:06

@quartata Object.keys

DJMcMayhem

Unicode isn't an encoding though

quartata

what

ATaco

Exactly

quartata

Oh I wasn't referring to you @DJMcMayhem

ATaco

Wait, I did say encoding there, didn't i?

quartata

21:07

woops

ATaco

regardless, UTF8!=Unicode

quartata

@Downgoat ELI5?

Conor O'Brien

@quartata you are talking about transpiling generators, no?

Downgoat

@quartata can you give example

quartata

@ConorO'Brien yes

Conor O'Brien

21:08

is the source in JS?

as in, are the generators you are trying to transpile written in JS

ATaco

It's usually a bad idea to expose locals to a different scope, are you sure this isn't the XY problem?

quartata

@ConorO'Brien no

@ATaco That's not what I'm doing

@Downgoat let me type up a sample

ATaco

All good then

Downgoat

@quartata wat

Object.keys is ES5 if that's what you mean

ATaco

One shouldn't always be warey of the XY problem.

Downgoat

21:13

oh

Conor O'Brien

@quartata then what are you doing

ATaco

Also, does the SE app have chat support?

Downgoat

Object.keys(this) gets you list of local variables

quartata

(int gen func):generator() {
  \for[i]([0..10)) {
    \yield(i);
  }
}

Turn that into

Conor O'Brien

into what?

quartata

21:21

var generators = [null];

function generator() {
  return {
    ...
    next: function() {
      if (generators[0]) {
        locals = generators[0].state;
        switch (generators[0].pos) {
          case 0:
            goto YIELD_0;
        }
    }
    for (var i = 0; i < 10; i++) {
      generators[0].state = locals;
      generators[0].pos = 0;
      return i;
      YIELD_0:
    }
  }
}

stupid markdown

here I'll type up a cleaner one

writing code on phones is hard

I hope you get the gist. Kind of like a duff device in terms of the loop trick

Downgoat

@ConorO'Brien I made functional babel plugin :D

Conor O'Brien

nice!

quartata

So what's the verdict doc

Conor O'Brien

@quartata you know that JS has generators right

quartata

I can try to do compile time reasoning on what's in scope but

@ConorO'Brien ES6.

or es7 can't remember

Is there a mod that can fix the code block?

El'endia Starman

21:28

@quartata Fixed it for you.

quartata

Beautiful thank you

El'endia Starman

The issue was a single empty line that didn't have four spaces.

quartata

yikes my indentation is wrong

oh well

@Downgoat Take another look?

Gabriel Benamy

me: admits in the comments that I'm pretty sure my code doesn't give the number I claim it does
me: gets 8 upvotes anyway

DJMcMayhem

Hahaha, this answer is amazing

2

A: In what spot would the new Star Wars Movie "Rogue One" go in the Machete Order?

Rod Hilton, the originator of Machete Order, answered this very question in his follow-up post to Machete Order. He includes a helpful diagram as his answer to this and future questions like it: Where Does Rogue One fit? "Since Rogue One is basically a prequel to IV, should Machete Orde...

Conor O'Brien

21:32

@quartata right but you can transpile it down from es6

quartata

@ConorO'Brien I would rather not have people have to run Babel when I could do it one step. Also ES6 generators aren't good enough for my purpose

Downgoat

@quartata oh I see

solution is to use babel

quartata

did you not read what I just said

Downgoat

... I don't think you understand what babel is

ATaco

Have you tried jQuery?

Downgoat

21:34

it's not like typescript or the other thing

It's just a JS code transform tool

people just use it for ES6 -> ES5

quartata

I am aware of that.

Downgoat

use babylon (babel-types? idk) to generate your AST and it'll let you handle all the scoping stuff without super-slow reflection and runtime tasks

quartata

But peope are going to have to run pytek first anyways

Also this is a fallback

And it shouldn't be that slow

ATaco

JQuery is good and does all things.

TimmyD

@DJMcMayhem Haha, nice.

Downgoat

21:36

Not sure what problem is but OK.

quartata

?

flawr

Does anyone here know an opensource online-proxy-thing?

Downgoat

@quartata babel is hardly slow

Conor O'Brien

function* asdf(){

}

quartata

Also you mentioned Object.keys how does that work

Conor O'Brien

21:38

"use strict";

var _marked = [asdf].map(regeneratorRuntime.mark);

function asdf() {
  return regeneratorRuntime.wrap(function asdf$(_context) {
    while (1) {
      switch (_context.prev = _context.next) {
        case 0:
        case "end":
          return _context.stop();
      }
    }
  }, _marked[0], this);
}

Downgoat

@quartata see my example anove

quartata

@Downgoat I didn't say Babel was slow at all. I said that the emitted code should not be that slow

I was under the impression that this was equivalent to window except in an object

Although this is in an object... hrmmm

ATaco

This I believe just refers to the object in scope, which by default is window

Downgoat

Why not write pytek in nodejs and do a webpack

quartata

kek

Do you know a good microbenchmarking tool for JS?

Downgoat

21:43

No

quartata

Bummer.

Downgoat

Don't do micropptimizations in JS please

bad idea

Probably will make your code even slower

quartata

Not what I'm doing

Just want to see if I should even bother with the web worker way

Downgoat

Actually wait yes

are you faimilar woth C++?

you can use v8s profiler

quartata

Link?

If I'm just embedding in C++ though might as well use Google Benchmark

Will it have Web Workers?

Downgoat

21:46

Probably

quartata

Wait, JS doesn't have goto.

Could have warned me >_>

Well crap. What browsers support Web Workers nowadays?

Downgoat

@quartata kinda sorta has

@quartata support is pretty good

quartata

I need pretty precise behavior goto-wise

Downgoat

caniuse.com/#feat=webworkers

quartata

Like if it doesn't translate exactly into a jump it's useless

TimmyD

21:51

goto Google and pick a better langauge

Downgoat

@quartata I mean there is continue but you're approaching it wrong if you're thinking goto

just do what babel do

quartata

Do you get why I need the goto?

I know of no other language construct that does that.

Downgoat

I'm not talking about GOTO I'm saying there is dlaw in solution to problem

TuxCopter

eviloverlord.com

lol

quartata

Chrome 49+, IE11+? rip

This was so easy in C. What the heck.

Downgoat

21:55

Lets be fair, no one care about IE users

quartata

I do.

And up until a couple months ago I was using Chrome 44.

Downgoat

Chrome support since beginning

quartata

I draw the line at recent past self can't use

@Downgoat Not according to it.

Downgoat

youre not looking at it correctly

hit show all button

quartata

Oh gotcha.

Downgoat

21:57

Also its IE 10+

quartata

OK that's pretty good support.

I'll roll with it.

TimmyD

@Downgoat I care about IE users because I'm one of 'em.

Downgoat

:O blasphem !

TimmyD

Careful, the angry yeti thing in my avatar will rip your arms off :p

Wow, that was a heck of a typo.

Conor O'Brien

@TimmyD same

only on occasion tho

Downgoat

22:00

I dont see anything besides logo of not sh

TimmyD

@Downgoat Hat?

Downgoat

No hat i see

El'endia Starman

@Downgoat Either you a) hate hats or b) need to refresh the page.

Downgoat

c) I'm on mobile

quartata

or c) they don't render on mobile

seriously

El'endia Starman

22:02

Oh. Welp.

quartata

That was quite the ninja

Mad respect

Downgoat

@TimmyD Haha I don't have arms >:)

TuxCopter

'night

Downgoat

@TuxCopter Question: are you antartic penguin

Destructible Watermelon

there are penguins in Australia

flawr

22:11

To hat or not to hat, that is the question.

hmm

New Main Posts

1

Q: Big numbers: Ultrafactorials

Ultrafactorials The ultrafactorials are a sequence of numbers which can be simplified with the following function: a(n) = n! ^ n! The resulting values rise extremely exponentially. Side note: This is entry A046882 in the OEIS. Also related are the hyperfactorials, a still quite huge, but a bi...

code-golf sequence factorial

flawr

Did I get so many upvotes on my Sandboxed proposal because upvoting on meta results in an increase of hats?

quartata

@Downgoat Web Workers seem pretty disappointing in terms of what I need. Is there no way to pause until a message or Thread.yield()?

It's just a pure async fire-and-forget

Xanderhall

I posted my first Jelly program. I am far too happy

Conor O'Brien

@quartata is there a way to programmatically obtain the items in a steam inventory?

quartata

22:18

@ConorO'Brien yes

Conor O'Brien

how?

quartata

inventory/PROFILEID/440/2?count=NUM for TF I believe

let me verify

Should give JSON back

@ConorO'Brien You might need to specify the language: l=english

It's a GET

New Main Posts

0

Q: bROKEN cAPSLOCK kEY fIASCO

bROKEN cAPSLOCK kEY fIASCO Some of your employees have broken capslock keys and you're too cheap to replace them. Help them out by creating the shortest program possible to correct their work! Simply convert each character in a given string from upper-case to lower-case and vice-versa... but the...

code-golf

Conor O'Brien

@quartata okay. how do I translate item ID's to human readable text

wait nvm

quartata

Looks like 5000 is the maximum count for one request

Conor O'Brien

22:28

5000 whats?

quartata

Items.

That's what count controls.

Regenerator's source code is unreadable. :(

trichoplax

@noɥʇʎPʎzɐɹC Interesting name for a company. Are the intended customers medical patients or vampires?

ATaco

So, I'm not sure if anyone here actually has any idea what my RProgN actually is, but anyway. I'm planning on replacing the currently bugging and barely used flow of control with functions that simply apply similar flow of control on 1 or more function arguments. Thoughts?

quartata

@Downgoat Just to confirm, setTimeout(..., 0); acts like a yield?

Python does that too but I wanted to verify

Downgoat

huh?

you can omit the trailing 0 btw

quartata

22:42

Wait, what?

@Downgoat Do you know what Thread.yield() does in Java?

Downgoat

no

I know how to make BankAccountTester though

quartata

It doesn't sleep for any particular amount of time, it just yields (gives up) the thread's time slice.

VisualMelon

@quartata setTimeout just schedules an async callback

Downgoat

so like performance.now()?

quartata

I don't want to a fixed tick rate in this busy loop because in idle time it'll be too slow.

VisualMelon

22:44

thread.Yield is completely different

trichoplax

TIL there are non-golfing languages that have a built in constant for TAU

Downgoat

@quartata yeah, that's not what you want

quartata

@VisualMelon I'm using setTimeout like sleep in this context.

VisualMelon

oh, I see

quartata

This is truly infuriating. How does emscripten even work

when simple low-level concepts can't even be translated

flawr

22:52

@trichoplax which one?

quartata

@Downgoat so what should I do?

I just want to sleep for a tiny tiny amount of time. 1 millisecond is too much.

setTimeout(..., 0) appears to do this so

ATaco

1 MS is too long. Only on PPCG.

trichoplax

@flawr The example I saw was Nim - it has both PI and TAU in the math module

flawr

I've actually never see anyone using tau = 2*pi

Just heard of people debating over it in the internet, but IRL never.

Also: You cannot eat tau.

ATaco

THE EMPEROR EATS TAU FOR BREAKFAST!

Maltysen

22:57

oh! its hats!

trichoplax

@flawr I've never used it before today either. I had assumed only golfing languages would have it, to save a byte

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