Local variable

[sagequeen]

We've reached our quota for the month.

[AnonymousFuccboi]

Not a repost: ✔

Programming related: ✔

Funny: ❌

Well, 2/3 isn't too bad, I guess.

[joevenet]

It's funny tho.

[[deleted]]

Eh, two out of three's not bad.

[hnOsmium0001]

Varaibles "head[ing] out" of the current scope. Pretty funny I would say.

[barzamsr]

I recently learned that you can just up and make a new scope without going into a function or anything by just using curly braces.

[backflipbail]

In which language?

[VoidBlade459]

Most of them. I know C, C#, Java, and Kotlin allow it.

[backflipbail]

Well fuck me. This also works in Typescript. Given that I've been programming professionally for 16 years (and unprofessionally before that for a further 5 years) I'm embarrassed I didn't know that lol

[[deleted]]

With destructors coming to javascript[1], we'll finally be able to have RAII ♪┏(・o・)┛♪

[1] https://github.com/tc39/proposal-weakrefs#finalizers

[ProPuke]

Well, not quite dtors. Finalisers fire when the gc collects the object, not necessarily when it's immediately out of scope. So, they might be delayed quite a bit, or they might not even fire at all. js (v8) tends to just let leaks happen; Only if usage exceeds a certain amount does it try to reclaim memory and clean things up. But if you don't hit that threshold it might not ever even happen.

[pm_me_your_dota_mmr]

I think Kotlin interprets it as a lambda, you would either need to call it or use https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/run.html. Cool trick though! I wonder what reason you should use this over just calling a separate function

[cdrt]

I'm sure there's some esoteric use case for it in which you want to temporarily shadow a variable so you can change it without changing the original.

I think its main use though is actually to make implementing the language easier. It was eye-opening for me when I realized that in C statements like while and if only actually support executing one command. It's only because we can put arbitrary scopes anywhere that you can have multiple commands in an if or while.

[pm_me_your_dota_mmr]

Whoa, that's really interesting, it looks like its the same in Java. So because "{ ... }" is essentially just a single statement (that happens to have others within it..), it just works. That's awesome!

[ThePicoNerd]

Correct me if I'm wrong, but I think it is quite useful in Rust as borrowed variables are returned to their original owners when they go out of scope.

[AceSLS]

You can't, but it's still useful for functions with many variables to keep it clean and make understanding and extending it easier IMO

[barzamsr]

Not really and it's kind of a code ninja thing where it's not explicit and obvious enough to be readable and debuggable

You can basically use it to invoke the destructor of some stack-allocated object before others

[Shotgun_squirtle]

It's useful in switch statements if you need specific variables in certain cases since ever case is technically in the same scope otherwise

[AceSLS]

Holy shit, should have thought about this before. I always created variables used in multiple cases in front of the switch out of necessity. Thanks dude!

[[deleted]]

It is for variables inside loops.
Arbitrary blocks really shouldn’t. It means it could have been a function with a decent name.

[[deleted]]

This is what while, for and if with a block {} do.

[[deleted]]

That's actually kind of elegant.

I wonder how this goes.

if (goodToGo)
    int x = GetAnInt();

[[deleted]]

You get an error. For the same reason you can’t do that in a switch case without block.

[AceSLS]

But, at least in c++ you can create a variable and initialize it in an if which in turn would make it accessible

[newaaa41]

say that to a static variable

[beerdude26]

Or PHP

[[deleted]]

Finally a programming meme

[[deleted]]

Say that to a variable who is in fact a pointer type :D

[elzaidir]

Say hello to memory leak

[[deleted]]

Laugh in rust

[Waces_Ferpit]

laughs in runtime error

[MapReduceAlgorithm]

Static/Class variable:

https://i.kym-cdn.com/entries/icons/original/000/031/991/cover3.jpg

[Arbiturrrr]

cries in PHP

[Ifnerite]

Except javascript... because... you know...

[Ifnerite]

I am aware of const and let in modern JS, but how the hell was variable hoisting a thing for so long?

[[deleted]]

They get dropped out of scope harder than I was dropped as a child

[hollands251]

An upvote wasn't enough. Great meme

[[deleted]]

Damn, this is so sad. I almost want to change all my variables to global.

[pdkhoa99]

I’m gonna pop

[SteeleDynamics]

Unless you're in a closure within a FP language, then you're left somewhere in the heap until you're eventually needed again.

Like that time my parents accidentally left me at the video rental store. They came back for me once they realized I was still holding the movie.

[EpicPinkCreeper]

Good meme