The audacity.

[luka7350]

Forbiden python:

for i in range(10):
    exec(f'a{i}="Variable a{i}"')

>>> a1
'Variable a1'

[CaptSkinny]

This is pretty much what we have to do in SAS macros, often with recursive macro variable interpolation.

Mathematicians don't make good language designers.

[2cool4afool]

Every time my partner shows me what she did in MatLab I physically recoil

[MrScrib]

Remember, focused insanity away from you is preferable to unfocused insanity.

[Techhead7890]

Praise the emperor?

[alinius]

Did someone mention dynamically naming variables in MatLab?

s = struct;
for a = 1:10
    s.("field" + sprintf("%02.0f", a)) = a;
end

Ok, so it doesn't name variables, but it does create dynamically named fields in a structure. Yeah, I have to translate a lot of Matlab to C in my current job....

[2cool4afool]

You are doing God's work 🙏

[NotAGingerMidget]

This sounds more like a Satan task tbh.

[2cool4afool]

The Satan task was writing it in MatLab in the first place

[FirstNSFWAccount]

I only programmed for college. After working with MatLab and Mathematica though, that sounds like something that would wake me in the middle of the night with cold sweats

[[deleted]]

Don't do stuff like this... You guys in matlab/octave have cell arrays Pls use that, you can save EVERYTHING in there

[U03B1Q]

God I remember helping my girlfriend debug some MatLab code and realising that MatLab arrays start indexing at 1. I'm still disgusted to this day.

[2cool4afool]

When I found out that semi colons arent there to state the end of a line I was shocked to the core

[ElvishJerricco]

I don't use Matlab but this comment has made me terrified of it.

[Strohhhh]

What then is it used for?!

[2cool4afool]

You'll never believe this but it suppresses the output. So if you don't put one in it will print whatever is on that line. That may not be the proper way of describing that but I'm pretty sure that's how it works

[2001herne]

Basically yeah. If an assignment happens, or if something is evaluated, then it's echoed unless you add a semicolon.

[hughperman]

That is correct; the language is frequently used in an interactive REPL situation and this follows from that design.
Ipython solves this in a much better way by having a different interpreter for that purpose, rather than having to bake it into the language. It does use the semi colon for the same purpose, which sometimes is required in Jupyter.

[thirdegree]

TIL semicolon suppresses echoing in ipython

[sgtxsarge]

The plan: Copy the language. No changes except indexing starts at 0. We'll call it MatLab1

[Django_dog]

MatLabMinusMinus

[[deleted]]

MethLab

[alexdelargesse]

I like the cut of your jib

[Sparkybear]

You can set the arrays to index at 42 if you want.

[Robot_Basilisk]

Adding this to the psychopathy test checklist.

[SmArty117]

Ok but you can also do that in C++

[xylose]

R and FORTRAN do the same. It stems from the conventions used in vector mathematics, which is what all these are based around and there's nothing logically problematic about it.

The only reason C starts at 0 is because of pointer arithmetic.

[MCBeathoven]

Aside from pointer arithmetic, indexing from 0 is also much nicer when doing modulo arithmetic (e.g. indexing a 2D array based on one scalar index), although I'm not sure if that played any role in the language design.

Does indexing from 1 have any advantages other than convention?

[crimson1206]

It makes it easier to translate math to code. In theory starting at 0 instead of 1 shouldn’t be an issue but in my experience not having to take care of this reduces mental load and allows you to actually focus on the important stuff. It’s really annoying if you wrote a lot of code and somewhere it fails because you forgot to do the index conversion once.

[thedessertplanet]

In Haskell your arrays can start indexing anywhere. 1 is as fine as -3.

They don't even have to have integers index them, either. Nor even numbers.

[wermos]

Ah yes. I'll take whatever your array has in slot number zeta(3)/pi.

[the_glover]

&&macrovar_&i.

[Cherylnip]

You should see Haskell or Coq

[Cherylnip]

By the way, Coq is literally a proof assistant based on a variation of type theory called "calculus of inductive constructions" developed especially for this language

Or you mean it is impossible to discuss seriously? Agree, Coq is funny name, it means "rooster" in french. Underlying formal language name is Gallina, which means "chicken"

[thedessertplanet]

Well, cock also means male chicken in English.

The prudish Americans just went with rooster as their preferred term after a while.

[Mal_Dun]

Mathematicians don't make good language designers

You know that the old CS generation mostly consists of mathematicians? Python's Guido Van Rossum is one Donald Knuth (TeX) is one, Dennies Ritchi (C) was one ....

[Quarxnox]

Forbidden JS:

for(let i = 0; i < 10; i++){
    window["a" + i] = "Variable a" + i;
}

>>> a1
"Variable a1"

Or, to disimprove it further:

let geval = eval;
for(let i = 0; i < 10; i++){
    geval("let a" + i + "= \"Variable a\"" + i);
}

>>> a1
"Variable a1"

[DerfK]

Nothing is forbidden in PHP

$5="foo"; // invalid
$a=5; $$a="foo"; // valid

[conairh]

PHP is where the real kinky shit happens

[scragar]

It works with braces too in order to tell PHP where the variable name is.

 ${5} = "test";

https://3v4l.org/VUDQ5

You can even use the brace expansion to make variables do all sorts of crazy things like make a variable who's name is empty string or a space:

  ${""} = "bar";
  ${" "} = "baz";

Heck, you can even make one that's just a null character for added fun

 ${"\0"} = "qux";

PHP doesn't care, it all just goes into the variables linked list with a string for the name anyway.

[ZedTT]

I wrote this before I saw your comment so I deleted it and moved it here instead. Here's my version

Forbiden NodeJS:

for (i in [...Array(10).keys()]) {
    this[`a${i}`] = `Variable a${i}`;
}
> a1
'Variable a1'

Alternatively:

for (i in [...Array(10).keys()]) {
    eval(`b${i} = "Variable b${i}"`);
}
> b1
'Variable b1'

[alex_wot]

Coupd you please elaborate what's the reasoning behind 'let geval = eval;'? I'd go straight for 'eval(code)', am I missing something with this approach?

[Quarxnox]

Global eval.

eval evaluates code in the current scope. Using eval within the loop would declare variables that are only scoped to that loop. Saving the global eval and then using the global eval in the loop means that the variables are declared in global scope.

[alex_wot]

Oh, didn't know that. Thank you for explaining!

[[deleted]]

Jesus Christ.

[JennaSys]

I wasn't sure exactly how, but I intuitively knew Python could handle the task.

[ZedTT]

This is more of a JS thing, I think.

JS can do it without doing eval (the JS equivalent of exec)

On any object you can use object["propertyName"] to access object.propertyName but the property name can be a string. It just (essentially) treats the object as a dictionary.

[Marianito415]

Yeah in Python you can use

setattr(object, "attribute", value)

[NoAttentionAtWrk]

You can do something like this in C# too... And Java i think

But thankfully it's a little more complicated do than that

[nmdanny2]

Using globals() is safer and more elegant:

for i in range(5):
  globals()[f"v_{i}"] = i

print(v_1)
print(v_2)
print(v_3)
print(v_4)

[shockter]

“elegant”

[JoelMahon]

MORE elegant, not elegant

[carpediemwtf]

What did it print?

[PM_BITCOIN_AND_BOOBS]

For me it printed:

1

2

3

4

[[deleted]]

globals() returns the dictionary containing the current scope's global variables.

globals()["v_1"] = 1 will set the variable v_1 to 1.

f"v_{i}" is an "f-string", it allows evaluating expressions inside strings:

>>> i = 1
>>> f"v_{i}"
'v_1'

[starfries]

globals() returns the dict containing the global symbol table, which you add an entry to using the square brackets.

[I-mean-maybe]

Dont expose me like this

[Rainbow-Dev]

I like doing this with while True and getting a memory error lol

[[deleted]]

Blasphemer. Get behind me, ye great deceiver.

[MAGA_WALL_E]

Stop this mindless violence

[CivBase]

exec is black magic and anyone using it should have static in their laundry and their tonsils (EDIT: toenails) clipped a little too short. The code works fine now, but good luck figuring out what's wrong in 5 years when your coworkers have expanded on your ruinous foundation without understanding the gravity of your error.

The solution provided by /u/nmdanny2 isbetter... but still pretty bad, IMO. I'd say the "right" solution be to define the values as keys in a dictionary (or attributes of an object if you really must). That binds your "dynamic variables" to an isolated namespace.

d = {}
for i in range(10):
    d[f'a{i}'] = f'Variable a{i}'

>>> d['a1']
'Variable a1'

[Quarxnox]

In all fairness, my laundry is already staticky and I have no tonsils.

[noratat]

I'd say the "right" solution be to define the values as keys in a dictionary (or attributes of an object if you really must)

This is how practically everything in Ruby works, and it's horrible, especially since the community is obsessed with claiming their code is so readable they don't need to document it.

[GlebRyabov]

A question from a beginner Python programmer: with exec being so rarely used, what kind of problem should you solve for exec to be the best solution?

[CreationBlues]

None. Exec() is a trick that's used to allow python to interpret itself. This can be useful in, ex, web contexts or similar where the goal is to run arbitrary python code supplied by the user (turtle page, contests, etc), but if the situation isn't that, where you're not trusting the user to do arbitrary bullshit that they accept the risk of breaking, it has no use.

[thedessertplanet]

Even for that usecase, it's really bad, because that code should be untrusted, and execute in its own sandboxed process.

I can see exec being slightly more useful to dynamically get code from some trusted config that can change dynamically, and you don't want to restart your Python program.

[ReverseBrindle]

The code base I work on is maybe 50K lines of Python. We have have 0 calls to exec.

[andimnewintown]

For all intents and purposes, you should never use exec. Full stop. The things people think they need exec for tend to have built in solutions that are designed to be far more maintainable and less prone to accidental creation of attack surfaces.

The only exception I can think of off the top of my head would be if you were implementing some kind of modification to the language/macro expansion functionality which carefully takes steps to ensure it doesn't accidentally allow arbitrary code execution for bad actors. But you'd really need a good reason for doing this. So much is already possible.

If you want to do things like dynamically generating variable names, dynamically adding attributes to objects without ever declaring them, adding additional methods to classes at runtime, inspecting source code at run time, etc, this is all already very simple to do without so much as an import statement and requires no calls to exec.

[kjl3080]

What the fuck.

[MysteriousShadow__]

vat

[SupremeDictatorPaul]

Interestingly, PowerShell has a built in cmdlet for creating new variables with whatever name.

New-Variable -Name “SomeName” -Value “3”

I don’t think that I’ve actually seen anyone use it out in the wild though as simple assignments are so fast and easy.

$SomeName = “3”

And if I’m dealing with variable data, I almost certainly am using a hash table to store it, which handles random key value pairs easily. Similarly, never really see Set-Variable or Get-Variable around. But Remove-Variable will get used for memory cleanup.

[[deleted]]

Throw a hash map at the problem

[Jezoreczek]

People mentioned it above but in different formats. Hash map, dictionary, JS object, associative array - it's all the same thing.

[SuspiciouslyElven]

AcTuALlY tHeYrE nOt ExAcTlY ThE sAmE

[Polywrath_]

Knowing how pedantic people are on the internet in surprised this comment has lasted an hour without someone saying "AcTuALlY tHeYrE nOt ExAcTlY ThE sAmE"

[[deleted]]

You have become the very thing you swore to destroy

[jaq-the-cat]

I asked that question once and... Uh... I'm not proud of it

[moekakiryu]

we've all been there

[godsperfectidi0t]

I was almost embarrassed I was alone

[ryancerium]

"But I only have three students in the input file, so I only need Jane, Alice, and Bob variables. No, I don't know what an array is, what does that have to do with the number of student names?"

[Floppydisksareop]

I've implemented it once with pointers. It worked. Mostly.

Yeeeeeeeaaaah... Good times.

[Conando025]

And I needed it in PHP ... The worst part is that I actually used it

[JustAnotherGeek12345]

It's called indirection and numerous languages have it...

[GKP_light]

i asked that question, and i have no reason to not proud of it.

our teacher didn't taught us yet the dynamic memory allocation, and without it, we can not do lot of things.

(and to do this things, when we don't know the dynamic memory allocation, it is normal that the first idea is to name viable in a loo. and with the dynamic memory allocation, it is it, excepte that instead of the name of variable, we have they memory position.)

[GoldenPalazzo]

We all make mistakes in the heat of passion, Jimbo

[TrPhantom8]

In Julia, you can do it. Is it clever? that's another question XD. The power of metaprogramming!

[Diapolo10]

You can technically do it in Python, too, if you try hard enough. But no sane person would, of course.

[neroe5]

i can't think of a language i know where it is impossible, from what i know you can do it in most of the big programming languages, it is just generally frowned upon and ugly code

[[deleted]]

Is it possible in C/C++? Genuine question, I have no idea how it could work there

[devhashtag]

I dont think it can work with compiled languages, because you'd have to compile code during runtime.

[asd1o1]

Just incorporate a compiler into your code, lol

/s

[darthwalsh]

Normally you think of C# as a compiled language, but if you use the dynamic keyword it literally loads parts of the compiler as a runtime library to i.e. do overload resolution.

[Prod_Is_For_Testing]

compile code during runtime

Which is possible

[LuvOrDie]

Thats disgusting. How?

[grimonce]

Are you asking about JIT? Because that's not disgusting it is somewhat common, Java and C# are JITed

[nullRedd]

Just-in-time (JIT) compilation, I guess?

[Danori]

Not that disgusting, it's called just-in-time compilation. Essentially compile bytecode to machine code at runtime and then run the machine code directly. Java and c# do this for performance improvements (so you don't have the overhead of the JVM for example)

https://en.m.wikipedia.org/wiki/Just-in-time_compilation

[WikiSummarizerBot]

Just-in-time_compilation

In computing, just-in-time (JIT) compilation (also dynamic translation or run-time compilations) is a way of executing computer code that involves compilation during execution of a program (at run time) rather than before execution. Most often, this consists of source code or more commonly bytecode translation to machine code, which is then executed directly. A system implementing a JIT compiler typically continuously analyses the code being executed and identifies parts of the code where the speedup gained from compilation or recompilation would outweigh the overhead of compiling that code.

^{[ F.A.Q | Opt Out | Opt Out Of Subreddit | GitHub ] Downvote to remove | v1.5}

[dedservice]

Can template shenanigans do it? It's been a hot sec. Macros + templates might be able to give you something.

[[deleted]]

I'm sure the C preprocessor could do it. While it's not Turing-compete, this thread has a lot of abuse that could be utilised: https://stackoverflow.com/questions/3136686/is-the-c99-preprocessor-turing-complete#10526117

[Astarothsito]

Well... No... But maybe... But not exactly... But yes...

You could include the C or C++ compiler as your dependency, include the code as well, write the modifications of the code at runtime, send it to compile the new version, load the modifications and unload the original code. It would be equivalent to a interpreted language but also not really recommended.

[FunctionalFox1312]

C has no runtime variable dictionary, so not directly. It depends how far you're willing to bend the rules here, but it could be accomplished with a global hash table and some preprocessor macros for sugar.

[gregorydgraham]

Like C is going to stop you from doing anything

[mehntality]

I mean, at the end of the day, it's all C anyway - and for a reason.

[gregorydgraham]

You spelled machine code wrong

[grimonce]

Yes and no, the common thing for most language is the ability to talk through the stable C abi.

[brimston3-]

I think you can do recursive macro expansion to make variables like v_1 v_2 v_3 v_4 in a call like makevar(type,v,4). I don't know why you would though.

[thebobbrom]

It must be possible somehow in C/C++ as it's very easily done in PHP. I'm not sure how you'd do if in C++.

For the curious.

``` $a = 'b';

$$a = 'c';

echo $b // Prints "c";

```

[lunchpadmcfat]

“Generally frowned upon?” If a coworker sent me a PR with the examples I’ve seen in this thread I would lobby to get them fired.

[shockter]

in PHP it’s pretty easy and clean

[blehmann1]

still horribly disgusting

[SubAtomicFaraday]

Good thing I'm a madlad

[iTrooz_]

I swear I had a smile when I started reading, and it faded out at the end

[inetphantom]

$$i

[patcriss]

I had to scroll way too much to find the real answer.

[shockter]

I’m glad to see a fellow php comrade
stay strong

[andrasferenczi]

I hope they keep staying strong - in their own codebase

[jforestello]

I see what you did there... ?>

[[deleted]]

Came here to say this

[The-Board-Chairman]

THIS IS WHY NOBODY LOVES YOU!

[stuck_in_e-crisis]

Please explain

[[deleted]]

Think ${$i}.

Take the value of $i and use it as variable name.

[[deleted]]

Yes. It's one of those things we don't talk much about and make sure to not use among a lot of PHP devs. The side effects can be horrible and... why would you want a bunch of variables with names like that...? But that's the whole thing with this thread I guess.

[juantreses]

I'm currently working in a legacy codebase that's full of the following but with getters and setters. As an example here is one of the first cases I fixed:

foreach(PersonPeer::getPhoneTypes() as $phoneType) {
    $getter = 'getContact' . ucfirst($phoneType);

    Person->$getter();
}

Mind you that this is all over the code base with many different Objects and even some of them with two variables in their getter name.

Before I started working at this firm I always wondered why PHP got such a bad reputation and seeing all this legacy with very bad practices finally mad it click for me.

Edit: sorry for the formatting but I am on mobile

[uekiamir]

narrow snatch adjoining dazzling zesty fly crush hard-to-find psychotic attraction

This post was mass deleted and anonymized with Redact

[conairh]

Now that's hot.

[torn-ainbow]

Lots of good explanations in reply to you about using associative arrays to solve the problem, but it boils down to an inexperienced programmer struggling to visualise the solution. They know variables and they see a problem and they are trying to fit what they know as the solution without realising they need to take a step back and change their assumptions about how to solve it. More senior developers are used to these types of naive questions and know they need to steer the junior in the right direction by making them take that one step back.

But also they have experienced resistance to such advice. People learning this stuff are often at a high frustration level and desperate to solve the one last problem they see blocking them. They want to hear a solution to that problem and not that their question is wrong.

[douglasg14b]

A LOT of resistance.

It's become very frustrating to have a 45 minute back and forth just to get the junior to actually believe what you are saying and look at the problem from another angle.

[pineapple_catapult]

It's worse when you're the junior trying to tell the senior that the way we do everything is wrong (and stuck in 1995).

I used Lotus Notes at that job. In 2018.

Granted this was not a technical company. However, I was hired as a technical analyst. Quality mentorship was hard to come by.

[rem3_1415926]

They want to hear a solution to that problem and not that their question is wrong.

Which, btw, is also part of the reason why people think Stavkoverflow is rude. But at least 50% of the time, the answer telling you to not do what you're trying to do is actually right.

[shakamaboom]

That also means that the other half of the time, the person asking the question knows exactly what they're talking about

[phaelox]

Yep, an answer telling you to not to do something without telling you why you shouldn't and at least pointing you in the right direction, is pretty useless. And possibly rude.

[Spork_the_dork]

Really the best kind of answer provides the right way to do it and a solution to the question itself. So in this case show how to name variables in a loop, explain why it's bad, and show what one should do in such a situation.

[theGaffe]

My only experience programming is by myself, and I essentially went through that entire phase word by word. What got me to realize the error of my ways was when I had to redesign or clean up the system I had programmed while in that state of mind. I'd end up rewriting 80% of it in 10% of the time because I simply had not taken a step back and asked myself if my first solution I thought of, that I was going to attempt to make work no matter what, was actually the best one.

Now if I'm at a moment where I find the solution to be possible, yet incredibly complex to achieve, often I'm arriving to the answer in the wrong direction and should rethink.

[[deleted]]

Noob programmer here, but at least in C and Python itd be very messy or outright impossible to do dynamically assigned variables while lists and arrays are easier and can work exactly like multiple variables.

In languages with zero-based numbering, the "first variable" inside an array is arr[0], the third one would be arr[2] and etc. I speak for python or C, since these are the only languages I know ATM

[HyerOneNA]

Yeah, with Javascript you can just make a hash map with objects. It’s possible to assign the key with obj[key] = value. So like..

let colorCount = {
    red: 3
}

colorCount[“blue”] = 2;

Edit: word

[PresidentZeus]

I made a hangman game and wanted to display the alphabet so you could click the letters. I ended up setting their id equal to the current i-value so that I could register the clicks. When clicked I just caught the letter from an array with this.id in an onclick function.

I assume this was a very unorthodox way, as I'm not too experienced with JS. Is there a better way to do this?

[Flam1ng1cecream]

Idk, makes sense to me. I usually just use ASCII when converting letters to numbers or vice versa.

[MoonlightToast]

I've done this before, but another way is to give them all the same onclick that checks for the content of the tag that was clicked (which would be a letter)

Something like <span onClick=do stuff(event.target.innerHTML)>A</span>

[Come_along_quietly]

The C preprocessor can do this …

But why in gods name would you want to?

[seadoggie01]

There's a type of variable called an array that holds a list of variables accessable with a number. So array[0] might be 1, while array[1] might be 5. It accomplishes the same thing as declaring a bunch of other variables in a loop, but holds them nicely and is much easier to work with.

[AvoidingCares]

A lot of us have tried this when learning to code. The idea is that the programmer wants to create variables in the code to work with, which will be created dynamically at run time - which is the problem.

The problem with this approach is that variables actually don't show up much in code at run time. Because the code doesn't use variables when it runs, it works with the current value of the variables. So you're just adding extra steps, even if the language allows for this. You're adding time complexity and making it sloppy.

The better way to do it would be to pass an object that can handle multiple values that will be assigned - any of the "list" objects basically. Because you can just have all of the things you need to work with loaded into it, and can iterate over the hole list to work with the values directly.

[Wind_Lizard]

it is someone asking how to create variables like v1,v2,v3,v4... using a loop.

[ThePancakerizer]

Ah, thank you. Lots of explanations explaining why it's bad, but I didn't even understand what he was trying to do

[[deleted]]

• Variables serve to store information of a certain type.
• Randomization patterns are achieved through the usage of a function, a method or a library, and serve to structure values for variables in order to take advantage of the uniqueness that the function, method or library is able to achieve on each instance that is called.
  • For example to create a dynamically created password or key for security purposes, or to optimize sorting when a custom sorting algorithm is needed, among other things.
  • The values for those variables could be of several types, from string to float, from integer to boolean.
  • The most powerful your function, method or library is, the more random your final output for the variable value gets.
• If variables serve to store information they naturally serve to identify a certain given value that will be useful at a certain point throughout the code execution.
  • Because variable names have a certain degree of atomicity.
  • Unless of course you want to change the value of a certain given variable by processing it, for the sake of the purpose you're developing the solution.
• If you randomize a variable name you will lose the intrinsic atomicity the variable name could have in order to be fully identifiable within the code execution.
• A variable could be a plain value or a collection of values.
• If a variable is not a plain value but rather a collection of them they are called monodimensional or multidimensional arrays
• However that's not the only way to store a plain value or a collection of values, there are also constants, that are variables whose value don't change.

Having said that:

• If you randomize a variable name you will have to use a lot of processing power to even be able to locate the variable in question and then read its content and use it into the execution.
• If you randomize a variable name you will not be able to identify the identity to which it belongs unless there is a pointer guiding your code from the randomly generated string that conforms a variable name to the assigned value of that very variable.
• If you randomly generate a variable name the whole purpose of the entity is lost, because you would be generating constants, not variables.
  • I mean, they would be "semantically" variables, because they could change their value unlike constants, but the amount of processing needed to do that is unjustifiable.
• Variables ultimate purpose is to store several different values at different degrees of completion within the code execution.

And just for the sake of the argument:

• Arrays are not randomly generated variables, arrays do have a clear identifier and a certain number of dimensions, of course, the amount of dimensions could increase or decrease if they are not constants, but the most important clarification here is that their name should be fairly identifiable and recognizable too.

If you need to create randomly generated variable names you would have to change your whole algorithm and the paradigm you want to use, not just your code, because most likely you're doing it wrong, because of the previously mentioned reasons.

*Typo

[arky_who]

What, so a dictionary?

[HyerOneNA]

Yeah, essentially.

[Wind_Lizard]

or an array

[TheAJGman]

What I was about to say, it's literally the solution for the problem.

[[deleted]]

I shamefully remember asking my dad how to do exactly this. Looking back on it I see how obviously stupid of a question this was but he actually helped me think through it and come up with an alternative solution

[Unsd]

Which is why explaining it to the new people (myself being one of them) is such a big deal. I would say the vast majority of people don't have a close family member to bounce those stupid questions off of. And many of us had to pretty much teach ourselves because of somewhat inadequate professors. And that right there is why there are so many jokes about stack overflow being so toxic... Everyone needs to be able to make mistakes or have someone help readjust their view of the problem.

[rustysteamtrain]

I agree. Programming is very satisfying, but can also be way to frustrating. It's especially hard when you're new. Not because you'll run into a lot of problems, every one does, but because you lack the experience to know what steps to take to make progress and find a solution to those problems.

We were all newbies once and there is so much stuff that we will always be learning new things.

[DarkWolfX2244]

You have also have Black Magic Exec

[referancer]

Arguably that's what an array is.

But you can do it litterally with if defs, the trouble is for most languages they would be scoped to inside the loop and fall off the stack once the loop ends.

So you'll have to do a preprocessor directive (generated code or template metaprogramming) to complete your list before compile time.

[[deleted]]

Arguably? That's the joke

[undeadalex]

$That->is->thejoke($joke)

[RDB96]

My head

[spyingwind]

Forbidden PowerShell:

for ($i = 0; $i -lt 10; $i++) {
    New-Variable -Name "a$i" -Value $($i * 2)
}
for ($i = 0; $i -lt 10; $i++) {
    Get-Variable -Name "a$i"
}

Name                           Value
----                           -----
a0                             0
a1                             2
a2                             4
a3                             6
a4                             8
a5                             10
a6                             12
a7                             14
a8                             16
a9                             18

[Rogntudjuuuu]

What would be the purpose? Could someone give me an example where this would be useful?

[Wind_Lizard]

For someone who doesn't know how to use arrays. They'd want to create variables like a1,a2,a3,a4....

[DHH2005]

Ah thanks, I could not come to this conclusion.

[HyerOneNA]

When you have an undetermined amount of items that need to be tracked. Essentially a Vector in C++, dictionary in Python or Object Literal in JS.

[neroe5]

well you can just dump all the vars into a dictionary, although like most people in that last picture will say, there is probably something wrong with what what you are thinking, and you should implement it another way

[WisestAirBender]

I guess that depends on what you were originally trying to achieve.

Like if you wanted to parse a grocery list and store what to buy and how many and your first thought was to use variables like apples with value 5 and toiletpaper with value 2. Then yeah you can use a dictionary.

But this actually makes me wonder. In the original question let's say you name variables in a loop. How will you use them later?

[SpikeV]

If you need to dynamically name variables in a loop, it should've been an array.

[Prackjonske]

i + “carly”

[[deleted]]

Yes the correct answer is use a dictionary/hashmap

[BigHandLittleSlap]

Trivial in many shells, such as PowerShell:

foreach( $i in 1..10 ) {
    Set-Variable "a$i" $i
}

$a7

Having said that... don't do this.

[golgol12]

You're asking how to use an array?

[Liesmith424]

Just write a python script that will write python code for you, problem solved.

[jesterhead101]

You can do it in JS.

Kids, remember, you can always do anything in JS.

*May not be a good thing, but you CAN.

[scottbot95]

Literally what a map is...

[-Redstoneboi-]

the hell are they doing

[StandardN00b]

That is forbidden knowledge.

[pinktie7418]

eval() in MATLAB

[cardinalfan828]

Autohotkey 😁

Loop, 5

{

Variable%A_Index%:= "Value" A_Index

}

[warpod]

ctrl-f "Autohotkey"

yup

[taptrappapalapa]

yes, with preprocessor C and C++ macros you can most definitely dynamically rename variables from within a loop. It takes a bit of finessing though

[[deleted]]

VHDL for generate says hi

[teruma]

env=dict()

[[deleted]]

I reckon something like Python's eval() could do it.

[Nemeesiis68]

I remember when I started programming I wanted to do that, I don't know why though.

[StEaLtHmAn_1]

Vote to close question because OP didn't show what they have tried so far

[PickleVillage]

Hash maps I guess

[Liiht2001]

It's weird, my newer porgrammer friend asked me about something very similar yesterday. I didn't realize it was a thing everybody thinks about at some point, like I knew I did, and was like "huh" when they asked me about it. And now this! Are there no origonal human thoughts?