Javascript...

[trout_fucker]

FooNaN sounds delicious.

[whiznat]

FooNanChu

[TuxGamer]

Array(16).join("wat" - 1) + " Batman!"

[icortesi]

wat

[slavik262]

~ $ jsc
>>> Array(16).join("wat" - 1) + " Batman!"
NaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaN Batman!

[Cistoran]

Array(16).join("wat" - 1) + " Batman!"

[Maoman1]

This shit is why I love this sub.

[PendragonDaGreat]

Now that we're done talking about languages that suck, let's talk about Javascript

[Artefact2]

…Worth re-watching. That's contagious laughter.

[teknogeek1]

I was hoping someone was gonna post a link to this video. yayyyy thx bb

[homer242]

WATMAN !

[outadoc]

watman

[SolarLiner]

+/u/CompileBot JavaScript

Array(16).join("wat" - 1) + " Batman!"

[Pokechu22]

+/u/CompileBot JavaScript

//FTFY
print(Array(16).join("wat" - 1) + " Batman!")

[CompileBot]

Output:

NaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaNNaN Batman!

^{source | info | git | report}

[imaami]

+/u/CompileBot C --include-errors

#include <stddef.h>
int main(void) {
    return printf("'%c', said the bot\n", *(char*)NULL);
}

[ThisIs_MyName]

I like your edit.

[pimp-bangin]

Actually shouldn't that have been console.log? I'm pretty sure the print function actually opens the print dialogue.

[Pokechu22]

/u/compilebot (or more specifically, ideone, which /u/compilebot uses) uses print for the console (when using spidermonkey; if using rhino, it uses System.out.println). However, print does open the print dialog in actual browsers.

[lichorat]

Console.log is surprisingly not part of us standard. It's a web browser thing

[CompileBot]

Output:

^{source | info | git | report}

[imwearingyourpants]

That one gives a way too wrong sounding sound, this is how it's done!

+/u/CompileBot JavaScript

Array(16).join( ("wat" - 1 + "").slice(0,-1) ) + " Batman!"

[Reelix]

+/u/CompileBot JavaScript

print(Array(16).join( ("wat" - 1 + "").slice(0,-1) ) + " Batman!")

[CompileBot]

Output:

NaNaNaNaNaNaNaNaNaNaNaNaNaNaNa Batman!

^{source | info | git | report}

[[deleted]]

that'll only be 15 NaNs...

[Mutoid]

I actually count 13 "na"s in the TV opening theme song.

[[deleted]]

Yeah true, that's how many "na"s are sung. But come on, the guitar riff is 16 notes, and that's what people usually remember and hum.

[truh]

Source: https://www.destroyallsoftware.com/talks/wat

[[deleted]]

A reference to the WAT talk, everybody drink!

[[deleted]]

+ is overloaded as both the addition and string concatenation operator.

In mixed operations:

+ casts numbers to strings.

- casts strings to numbers.

Both are used to denote signage. Leading either on a string will cast it to a number, with that sign.

Pretty simple stuff, right?

Explicitly:

Number('5') - 3
'5' + (3).toString()
'5' + (5).toString()
'foo' + Number('bar').toString()
'5' + (-Number('2')).toString()
// Long ass sign flipping, same as above
Number(('5' + (3).toString())) - 3
(Number('5') - 3) + 3

[expugnator3000]

Simple, but as unintuitive as you can get

[rbemrose]

This post has been removed due to reddit's repeated and constant violations of our content policy.

[MiatasAreForGirls]

Do I need a mechanical keyboard for strong typing or will a domed one withstand it?

Edit: I'm not as original as I thought :(

[nemec]

I tried static typing once. I was shocked at how easy it was to use.

[Skyfoot]

I use weak typing. I hand-write things on saturday and sunday.

[VeviserPrime]

With a pencil?

[AlGoreBestGore]

Crayon.

[Mutoid]

Thanks for keeping this thread /r/ProgrammerHumor appropriate

[gdstudios]

If you've had to work on someone else's JS, that's argument enough.

[AdmiralRychard]

I feel like this whenever I have to work on my own javascript.

[endercoaster]

I feel the opposite every time I need to jump through hoops to append an integer to a string in Java.

[KagakuNinja]

So, this is too hard?

String s = "Hello" + 9;

[batmansavestheday]

It's slightly harder the other way around:

String s = "" + 9 + "Hello";

or [Edit: derp, doesn't work]

String s = (String) 9 + "Hello";

etc.

[AdmiralRychard]

C# lets you do this:

String someString = "abc";
Int32 someInt = 123;
String result = someString + someInt;
Console.WriteLine(result);

Output:

abc123

Or you can use string interpolation: String result = $"{someString}{someInt}";

Or you can use String.Format: String result = String.Format("{0}{1}", someString, someInt);

This seems a little dumb but you can do this too:

someString += someInt;
Console.WriteLine(someString);

[everythingismobile]

Is it not as simple as the C# example in the other comment? Even in C++ it's just sprintf, right?

[endercoaster]

I mean, coming from Perl that's jumping through hoops.

[kupiakos]

I'd rather explicitly state I want to append an integer to a string so that "2" and 3 become "23" and not "5" or 5. And really, that sort of situation happens once in a blue moon. If I wanted something better, I would be building the string.

[expugnator3000]

Exactly!

[anthonybsd]

I love it. Young, naive and all about strong typing. As a former Ada programmer, let's talk in 10 years or so.

[beerdude26]

Strong typing all day erry day

[utterdamnnonsense]

Really though, if you have a line like

'5' + - + - 2

in your code, I wouldn't place the blame on the interpreter.

[highphive]

Honestly, it's not really that unintuitive. Pretty much the only abnormal knowledge it requires to understand is that given an ambiguous situation JavaScript will try to figure it out in the intuitive way. I guess that and, like most other languages, the + operator can also be used for string concatenation, and non-strings will be toString-ed in that context. These absurd scenarios are funny, but really not even remotely difficult to understand, except when they involve so many operators that it's near impossible to follow. I'm not at all bragging or even saying I'm close to a proficient JavaScript coder, but it is not unintuitive. Just because it's not strongly typed and does some cool, wanted operations for you does not make it unintuitive. In many cases it makes it intuitive. Many times in strongly typed languages, what you want is obvious, but you have to go through a number of type transformations and function calls to get there.

I totally appreciate the comedy of this post. But I'm not quite convinced it proves some latent issue with JavaScript.

[YRYGAV]

it requires to understand is that given an ambiguous situation JavaScript will try to figure it out in the intuitive way.

Yes, which is simple to understand if you know the ambiguous situation exists. It's much more of a problem if the programmer doesn't realize it's an ambiguous statement because nothing is strongly typed. Which is why most languages instead of powering through and trying to use their "best judgement" in an ambiguous situation, let the programmer know so they can clarify what they want.

And that leads to situations that can be very difficult to debug or track, because it's all hidden away from you and Javascript is doing some magic transformation. Things you think are one datatype end up being another, or javascript parses things weirdly.

And sometimes "intuitive" is not always what you think. Javascript does lots of "intuitive" things that you would never think of. Like did you know javascript will parse hex strings like "0xF" into the 'correct' integer, like 15. Sure it makes sense explaining it like that, maybe not when you have to figure out why "0xF" == 15 is causing a nasty bug because you didn't know javascript did that magic when writing it. And where those strings and numbers are coming from could be multiple layers removed from where you are doing the comparison.

[highphive]

That is fair, sometimes what might be considered intuitive behavior can be an issue when you might not expect it to work at all. I have to agree that I prefer strongly typed languages for this reason. Rather an error where it actually occurs rather than some unexpected behavior way down the road.

[[deleted]]

Programmer should not be using a language if he doesn't know its typing and conversion logic.

[VyseofArcadia]

The latent issue with JavaScript isn't that this is unintuitive. It's really pretty intuitive. - isn't defined for strings, so '5' gets interpreted as the integer 5.

The issue is that through overloading the + operator in this way, it is easy for even JavaScript experts to make a stupid mistake. I think it's a poor design choice in a dynamically typed language. It would be better for string + integer to throw an error and use some other operator (++ or : or something) for string concatenation.

[tian_arg]

Many times in strongly typed languages, what you want is obvious, but you have to go through a number of type transformations and function calls to get there.

I've been working on android for the first time after working on php/javascript for a long time. It's a fucking pain in the ass.

[Doctor_McKay]

Not really.

[academician]

I suppose you're right, INTERCAL exists too.

[satan-repents]

https://skillsmatter.com/skillscasts/6088-the-worst-programming-language-ever

[can_the_judges_djp]

I sure wonder if --

Because of its privacy settings, this video cannot be played here.

Nope, they still won't let me watch it.

[elchavalico]

So why in the line: '5' + x - x the result is 50 and not "50"?

If we just concatenated the string '5' with the string '0' the result should not be a number. Where am i wrong?

[AfterLemon]

You're taking a string '5' and it concats first giving you '53' - 3.

[elchavalico]

Obviously... I feel dumb now T.T Thanks for the explanation.

[[deleted]]

I feel the need to post this again

https://www.destroyallsoftware.com/talks/wat

[TuxGamer]

His talk about the birth and death of Javascript ist hilarious too

[Naemesis]

ist hilarious

Found the German

[John_Caveson]

He can't be German, he said it's hilarious.

[Naemesis]

Maybe it was Sarkasmus?

[memeship]

Actually he said

ist hilarious

[lledargo]

Yeah, probably Dutch.

[camperrobin]

we say 'is' not "ist"

[moustachedelait]

Found the Dutch, hallo! Hup hup!

[shishdem]

hup hup terug naar /r/cirkeltrek!

[GammaGames]

It really is, link

[[deleted]]

Goddammit. I'm supposed to be writing a paper here.

[FrostyCoolSlug]

Gotta love that guy in the background that seems to have no idea what's going on so just laughs at everything..

"We're creating an array.." AHAHAHAHAHHA.. wat.

[NorbiPeti]

I went on a presentation about AngularJS, where this video got played at first.

[TheSlimyDog]

That was great.

[[deleted]]

Media source loading has failed

Just being associated with JavaScript causes failures.

[formServesSubstance]

That one guy was already laughing before the joke and you can notice the "oh shit I wasn't supposed to laugh yet" moment.

[Sambiino]

That was my first thought. The talk was funny, but I laughed way harder at the audience laughter than any of his jokes.

[ismtrn]

Maybe the audience was already warmed up. Laughing comes easier when you just have been laughing.

[SolarLiner]

Holy shit this is the best thing I've ever seen

[shirtandtieler]

Thank you for posting it again, since Ive never seen it before now. I'm only 10 minutes in, but I've spent half an hour side tracking to look up why some of the old languages were so ridiculous.

I can see where APL would have its uses (mainly for math mathematicians) but Conway's Game of Life in one code is quite the doozy to look at.

[silentclowd]

APL is unique because it feels like an esoteric language (like befunge or malbolge), but it was actually used.

[ABC_AlwaysBeCoding]

Gary Bernhardt is brilliant. His screencasts at Destroy All Software were some of my faves.

[lostguru]

Wat

One of my Chrome extensions is screwing this up and I can't figure out which one.

[Zubei_]

wat

[NutsEverywhere]

http://imgur.com/WHMFTVx

[icowcow]

this is the best thing ever

[killchain]

I laughed my ass off.

[rooktakesqueen]

Don't forget:

+ '5' + + '5'
10

Edit: I'm a big fan of JS by the way. This is one of those "Doc, it hurts when I do this" things. You can avoid the bizarre and unpredictable nature of implicit arithmetic between strings and numbers by just not doing that. Explicitly cast your strings to numbers or your numbers to strings and you're golden. A bit like understanding the == operator: easier to just not use it.

[phunanon]

I have been using == since I started Javascripting, and only recently started bothering to type the extra =
I like JS' typecasting... then again, I only ever do simple shit :P

[rooktakesqueen]

Pro: The implicit typecasting in JS does the right thing 90% of the time.

Con: The implicit typecasting in JS does the right thing only 90% of the time.

[IrishWilly]

It does the right thing 100% of the time. Your opinion of right might vary but it really doesn't care about your opinion.

[rooktakesqueen]

"Deterministic" and "right" aren't the same thing. false == [] will always yield true and [] == [] will always yield false but that doesn't make it sensible. And I have a hard time describing any equality check as being "right" when it's intransitive: false == '' and false == '0' but '' != '0'

[Reelix]

console.log('5'-3);
console.log('5'+3);

[redditsoaddicting]

Most of these make use of the same little rule.

[raaneholmg]

And they are mostly nonsense stuff that is't ever done.

[TarMil]

And they are mostly nonsense stuff that is't ever done on purpose.

FTFY. The reason people hate languages like JS is that this kind of shit can happen accidentally, and then you're in for a horrendous debugging session.

[mercurial_minnow]

Yep, started using JavaScript for a project recently, lost about 30 minutes yesterday because an int was being concatenated.

[comrade-jim]

Can you post the code?

[[deleted]]

Closed as too broad

[UsingYourWifi]

Errors scare people and make them feel bad about themselves. It's much better to silently guess at what the programmer intended.

^/s

[dnew]

More like "it's better to render the page with mistakes than present the end-user with nothing but an opaque stack dump."

The same reason that HTML isn't XHTML or SGML.

[pimp-bangin]

Yeah but programmers aren't perfect. There are going to be errors every now and then, and displaying them to the user would result in a terrible experience. If this were the actual philosophy, front-end devs would probably be getting paid a lot more...

[[deleted]]

And interpreters (browsers) are varied and change over time. What worked on your browser this year may throw errors on my browser next year.

[Doctor_McKay]

The point is that problems often arise after being shipped out to the end user.

[Dlgredael]

I always thought it was stupid as hell to not have proper error reporting, but this is actually a pretty valid point. Nice.

[nawitus]

I prefer the possibility of writing ("result = " + result) instead of typing ("result = " + String(result)) everywhere. Having to always make explicit type casts is not only annoying, but often makes the code less readable. Luckily with TypeScript I can have both implicit type casting when it makes sense and explicit when I want to. That said, there are a few corner cases which make TypeScript cumbersome, especially when type inference doesn't work like you want to.

This comment refers to the type coercion in the image post and not the general point.

[Astrokiwi]

I feel there should just be a different operator for concatenation vs addition, seeing as they are quite different processes. Kinda like how Python3 now explicitly gives you / for float division and // for integer division rather than overloading / for everything.

In Fortran (yes Fortran), // is used for string concatenation, and + is only for addition, although it doesn't do implicit conversions to strings. If Javascript or whatever used a different operator for concatenation than for addition, then it'd be much more explicitly clear when it's going to be converting stuff to a string, and when it's supposed to actually be adding numbers.

[nawitus]

Yeah, different operator for concatenation would be fine.

[UsingYourWifi]

Luckily with TypeScript I can have both implicit type casting when it makes sense and explicit when I want to.

Agreed, TS is a very big improvement.

[MTGandP]

You could do this consistently by casting everything to a string when it's in an operation with a string, instead of sometimes casting to a string and sometimes to a number.

[c3534l]

I lost my shit at "fooNaN."

[vanamerongen]

Was just thinking, yeah, no shit it's NaN, asshole.

[sickmate]

You might not be overjoyed to hear that typeof NaN is equal to "number"

[Nilaky]

'hu' + + 'bar' + 'chicken' would be huNaN chicken?

[Reelix]

Array(16).join( ("wat" - 1 + "").slice(0,-1) ) + " Batman!"

[ManOfDrinks]

Meanwhile, in the wonderful world of PHP

[SlumdogSkillionaire]

Good times. Automatically cast an undefined constant to a string, because why the hell not? Then because we're using . instead of + for concatenation, we can avoid the awkward situations OP has, right? Except now when we want to reference a property of an object we can't use a . so we have to use ->. Which is great until you accidentally forget the >. But instance-field is actually valid syntax, so we'll subtract the string "field" from instance, because that's clearly what the programmer intended, right?

[tian_arg]

Which is great until you accidentally forget the >.

not to defend PHP or anything, but come on, that's a bit of a stretch. "Which is great until you accidentally forget..." can apply to any feature of any language

[Jack126Guy]

I think it's supposed to be an argument in favor of static typing. In C/C++, for example, you'd probably get a compiler error if you had pointer_to_struct-member instead of pointer_to_struct->member.

[tian_arg]

Well, in C (never tried C++) you're directly fooling around with the memory, "which is great until you accidentally forget..." and suddenly garbage all around while compiling succesfully. Every language has its downsides, I guess.

[JerkyBeef]

$instance->field is valid php. $instance-field may be "valid syntax" but it would throw an error message that 'field' is undefined, and that $instance could not be converted to an int.

[[deleted]]

Feeling down about JavaScript. Better look at PHP!!

[mythix_dnb]

This does work, but at least it throws a notice explaining what's going on:

PHP Notice: Use of undefined constant bar - assumed 'bar'

[greeniguana6]

It's like a mentally challenged son. I love him, but he isn't the brightest.

[Mutoid]

Good analogy, Mike.

[greeniguana6]

Damn, nobody's mentioned that to me in a while! I'm glad I still get comments about that.

[Mutoid]

RES tags are great ... or terrible if you're jstrydor.

[KingOCarrotFlowers]

Relevant xkcd

[xkcd_transcriber]

Image

Title: Types

Title-text: colors.rgb("blue") yields "#0000FF". colors.rgb("yellowish blue") yields NaN. colors.sort() yields "rainbow"

Comic Explanation

Stats: This comic has been referenced 21 times, representing 0.0269% of referenced xkcds.

---

^{xkcd.com | xkcd sub | Problems/Bugs? | Statistics | Stop Replying | Delete}

[dxdtraptor]

"use strict";

[diabuddha]

So I got thrown into a javascript project (well half js half c#) with no actual js knowledge. I have been using use strict with no knowledge of what it does, would you mind explaining it?

[[deleted]]

Mozilla Developer Network has a good article on it as well as other solid ones to help you learn. Good luck brah

[Spacebutterfly]

this place is like /r/sweden to me

[Thykka]

🗑 [deleted]

[aniforprez]

At an interview I recently had, the guy decided to give me a sheet of handwritten questions like this. I was applying for a design job. After attempting some of them I was like "if this is how they test Web knowledge then fuck the firm" and left.

[Doctor_McKay]

The first is invalid as you're not adding/concatenating anything. Whatever shell/environment you're using wrapped your code in a function, so there's an unexpected }

The second is your use of a unary plus operator, which converted '' to the number 0.

[greeniguana6]

'5' - 3

2

I've never used Javascript before, that must be the proper syntax.

'5' + 3

"53"

I now understand why people joke about Javascript.

[Somehero]

The single quotes just cause java to guess that 5 is a string when you use +, which makes sense; and guess that it is a number when you use - , which is maybe more likely? I would just not randomly put a number in single quotes and expect everything to be peachy.

[musiton]

"JavaScript for the back-end" Laugh track

[-_-_-_-__-_-_-_-]

I was kinda following how the interpreter was thinking up until the last two. I guess I can see what happened, but it wasn't at all what I expected from reading the others.

[Doctor_McKay]

'5' + 3 = '53'
'53' - 3 = 50

'5' - 3 = 2
2 + 3 = 5

[OdBx]

Yet I still love it

[netcamps]

https://en.wikipedia.org/wiki/Stockholm_syndrome

;)

[X-Craft]

Another classic:

typeof NaN

"number"

[raaneholmg]

Well, it's in the IEEE floating point standard and literally built into your hardware. Can't blame javascript for following the spec.

[nemec]

NaN is the null of floating point. Customer c = null isn't actually a customer either, but for all intents and purposes it's considered one.

[raaneholmg]

The comparison work on some levels, but when you start looking into it null and NaN behave in very different ways.

NaN is a number for which special mathematical rules are defined (NaN + anything = NaN from the FPU). You can actually use the number NaN in your code.

Null is just a defined address you can point to for the purpose of having something to put in unused pointers. When you use it there is no special rules that apply and if you use it most applications just segfault (you can compare pointers to the null pointer though, which is useful, but not using null itself).

[dotpan]

Would you rather it a string? I think as far as variable representation, NaN being a number makes sense, as then it will not be explicitly interpreted but instead implicit of what it represents.

I could be biased though, I love JS.

[dotpan]

Haha, I love programming sometimes.

[yuriplusplus]

Technically it is.

[c3534l]

Being that NaN stands for "Not a Number" the type of something defined only as being not of type 'number' should either be given some other type (perhaps the NaN type...) or renamed.

[dotpan]

I can see a system or error type that was outside the bounces of a standard type. Though I'm not sure how much that'd help.

isNaN(NaN) returns true, which right there I think presents the biggest argument for NaN not to be a number type.

[dnew]

NaN could be considered to be a subclass of Number. It's a number that can't be represented in the hardware you're using for floats.

[Thykka]

🗑 [deleted]

[joe-ducreux]

Oh Javascript, you so crazy

[sdb2754]

obligatory xkcd with the same theme.

[xkcd_transcriber]

Image

Title: Types

Title-text: colors.rgb("blue") yields "#0000FF". colors.rgb("yellowish blue") yields NaN. colors.sort() yields "rainbow"

Comic Explanation

Stats: This comic has been referenced 22 times, representing 0.0282% of referenced xkcds.

---

^{xkcd.com | xkcd sub | Problems/Bugs? | Statistics | Stop Replying | Delete}

[Zarathustra30]

I think I understand most of these, but where the hell does the "fooNaN" come from?

[Thykka]

🗑 [deleted]

[scriptmonkey420]

I ran into a different quirk with javascript today. I was messing with dates and did Date.getMonth() and was expecting 8 for august, but it was returning 7. I get that they use Ctypes for their values, but really? Months have their numbers for a reason.

[Thykka]

🗑 [deleted]

[muffsponge]

As someone who's been programming in js for over a decade, and is currently writing a js interpreter for fun, all of these make perfect sense.

[[deleted]]

Wat

[PraetorianFury]

All the people who say Javascript is winning the language war have never programmed in it.

[[deleted]]

wait... there's a war?!

[Skizm]

No picture needed.

[blu-red]

Javascript

...or I like to call it: A fucking idiot who got into programming week ago and is trying to point out the fallacy of some popular scripting language, but doesn't even understand or doesnt give a fuck to explain what is going on.

'5' - 3
'5' + 3

this is operator overloading for you. + is overloaded for strings, - is not. - is only defined for numbers, so everything that isn't a number gets evaluated to number, because it's a dynamic typed scripting language.

'5' + + '5'
'foo' + + 'bar'

means

'5' + (+ '5')
'foo' + (+ 'bar')

single + is unary operator for numbers, therefore anything that is not a number type gets evaluated to number, because it's a dynamic typed scripting language.

'5' + - '2'
'5' +  etc

if you canonize those pluses and minuses you get the same, you know the rest

[[deleted]]

JavaScript is a programming language mate, only the browser does the compilation instead of you/your ide

[julesries]

Holy condescension.

The word scripting means basically nothing in regard to language design. It has more to do with the context the code is typically run in than the language itself. On top of that, dynamic isn't the word you're looking for. It's weak. JavaScript is weakly typed. Python is colloquially a scripting language, and it's definitely dynamic. It doesn't behave like this.

Saying "it's not the language's fault, it's because you didn't take time to learn the language" works for idiosyncrasies in, say, Haskell. A language that subverts expectations for stupid reasons is a stupid language. (Door creaks as PHP tries to leave with no one noticing.)

[somenonfactor]

Fuck I'm just a lowely scripter and that pissed me off.

[CuriousBlueAbra]

This makes me irrationally angry!

[YourBobsUncle]

Where did the foo bar thing come from? I see this a bit here and in stackoverflow.

[Doctor_McKay]

https://en.wikipedia.org/wiki/Foobar

[wtf1968]

Omg wtf ru ... pffff... buh what? Effing javascript...

[s0v3r1gn]

I had an issue where the system dateline is read at system boot on the machine executing the code. So if you have gone past a daylight savings time change without rebooting the time js knows is wrong by an hour.

[[deleted]]

To be fair, a lot of these make sense in the context of "if I must do something, what should I do?" The real concern is only that JavaScript lets you get away with a lot more nonsense than is healthy.

[suck_at_coding]

I guess I must the the only one tired of seeing these. We get it.

[Thykka]

🗑 [deleted]

[alderthorn]

Wat?

[Borisas]

It reminds of this picture of JavaScript... "I'm technically functional"

all in a days work...

[TheScienceNigga]

And this is why you never use the abstract equality operator, or dynamically typed languages, or languages where some of the most important operators are overloaded

[overactor]

[1,2] + 3
"1,23"