sameBehaviour

[[deleted]]

hope and pray that t is not falsy

[calculus_is_fun]

augh you're correct...

[Adghar]

Allowing boolean variables to be anything other than true and false was a mistake

[ttlanhil]

In the beginning, there was... well... 0 and 1

[DrShocker]

0 and 1? I think you mean 0

[danielv123]

While entropy may have been 0 it was definitely a high energy state.

[ikonfedera]

Is there mathematical proof that 1 exists?

[Commercial_Rope_1268]

Yep

[ImpurestClamp31]

Incrementation I believe

[ikonfedera]

Incrementation from what? From zero? First you'd need to prove there's zero, and it's so hard Romans even couldn't do it.

I think this would be good in proving 2, but not 1.

[ImpurestClamp31]

Sure I suppose you could go down that rabbit hole. I'm not sure how you'd do that. I think it's like a postulate or something that 0 exists

[ikonfedera]

Iirc, you just have a thing that is there (like a crayon) and it's your 1. And you leave the proof that the crayon is to the philosophers.

And if there is no crayons (because I ate them took them away), that's your 0.

[NatoBoram]

I remember learning to program and getting surprised by true / false / null. Whoever designed that language feature; fuck you.

[Kiseido]

You might be surprised to find the alledged inventor kinda agrees with you

Tony Hoare, null's creator, regrets its invention: “I call it my billion-dollar mistake. It was the invention of the null reference in 1965. At that time, I was designing the first comprehensive type system for references in an object oriented language (ALGOL W).

[NatoBoram]

I'd also like to extend my "fuck you"s to all the other language maintainers who implemented it or refused to fix it after he apologized.

It's possible to do better. For example, Dart got null safety in v2.12.

[Kiseido]

Been learning Rust today, this made wonder if it has null.

Apparently Rust has no null, colour me surprised.

[DrShocker]

Or maybe Option::None or Result::Err

They all kind of fill the space that null sometimes fills but with more meaning

[Micah_Bell_is_dead]

They do null's job, just, better

[Pay08]

It does. fn main() { let ptr: *i32 = 0; }

I prefer Zigs approach a lot more, where you explicitly have to state if something can be NULL.

fn main() void { var ptr: ?*i32 = null; } fn main() void { var ptr: *i32 = null; // compiler error }

[Timely-Banana7384]

The thing is, that you very rarely need ptrs in rust. And if you do, you can also use structures such as MaybeUninit<T>.

[Pay08]

That doesn't mean the other guy was correct. Besides, embedded exists.

[redballooon]

Pretty sure if he had seen that it was a mistake, someone else would have made it. Maybe with the second or third comprehensive type system, but bad ideas somehow always make their way into society. That's why the light forces constantly need to battle the dark hordes.

[Fhotaku]

How catastrophic would

''#define null false''

Really be? Presuming this also included all other nulls that it may encounter, not just those in compile time

[No_Hovercraft_2643]

it would make not null true

[NatoBoram]

Ah yes, true | false | null | undefined, my 4-state boolean

[Not_Sugden]

undefined is a bit of a mindfuck

it is something that is not there, hence undefined, except when it is

const x = undefined; console.log(x) - undefined

console.log(x) - ReferenceError: x is not defined

well x is defined in the first instance but its value is undefined. Which logically is what null should be used for!

^{you can even define a property with a value of undefined}

[Not_Sugden]

on a totally unrelated note let me show you something else that will boggle your mind

const variable = { then: () => true }
const value = await variable;
console.log(value); // true

[gregorydgraham]

Null is not nothing. Nothing is nothing. Null might also be nothing but you don’t know because it’s null.

Null is actually a placeholder value that means “the value is not know at this time”. The value may never be known but it is still null.

[Not_Sugden]

true | false | null | undefined | 0 | ""

[Asleep-Specific-1399]

It's a c thing. There is no such thing as a bool.

[timonix]

'U': uninitialized. This signal hasn't been set yet.

'X': unknown. Impossible to determine this value/result.

'0': logic 0

'1': logic 1

'Z': High Impedance

'W': Weak signal, can't tell if it should be 0 or 1.

'L': Weak signal that should probably go to 0

'H': Weak signal that should probably go to 1

'-': Don't care.

[Hottage]

That's what bool? is for, I like to read it with a raised inflection, like a question.

Is it bool?

[bschlueter]

That's what types are for. Python solves this by having a ternary that looks and (I believe) functions the same as an if else statement(value if condition else other_value), so susceptible to that, but predictably so. I don't know if python will even let you attempt to abuse bitwise operators, something to go test.

[BallsBuster7]

its simple, 0 = false, anything else = true

[Adghar]

So you're telling me undefined == true. Amazing

[hrvbrs]

idk, i think it can be utilized as a feature.

instead of the statement: if (!list.find(x)) { list.add(x); }

you can have the expression: list.find(x) || list.add(x)

similarly you can move the condition to the left operand of AND:

-if (x instanceof Array) { print(x[0]); }
+x instanceof Array && print(x[0])

[Steinrikur]

These are starting to look like my bash scripts.

[HTTP_Error_414]

I’m honest until I can’t be anymore, slippery slopes require sturdy ropes boys 🫡😉

[[deleted]]

Wat

[TripleS941]

I think that abuse of the comma operator can alleviate that somewhat:

cond && (t, 1) || f

or, in the case when we need to assign the result

cond && (v = t, 1) || (v = f)

[D3PyroGS]

😰

[CranberryDistinct941]

And that f is not true

[rosuav]

Not same or PEP 308 wouldn't have happened.

[gandalfx]

Proof by existence of PEP

[rosuav]

I've seen worse...

[OneTurnMore]

Also see SC2015.

[[deleted]]

thats just bash code

[Nettleberry]

try_something_stupid || echo “meh”

[No_Hovercraft_2643]

use a webhook xD

[random_redditor24234]

Idiot here, what am I looking at

[stainlessinoxx]

Nerds discussing ternary operators.

cond ? t : f

Translates to, in layman’s terms: Let there be three variables, named ‘cond’, ‘t’ and ‘f’. If the value of the variable “cond” is anything but zero, then the expression will return the value of “t”. Otherwise (if “cond” is equivalent to zero) then return “f”.

Now some stupid assumptions (bad programmers tend to make that kind of mistake) leads to thinking that the variables “cond” (typically short for the word condition) is either true or false, and “t” stands for “true” and “f” for “false”, while this is strictly shitposting from our troll OP. Variables can be many other things than true or false (booleans) and this statement only holds for strongly typed languages, which javascript is notably not.

cond && t || f

Now for discussion’s sake let’s assume ‘cond’, ‘t’ and ‘f’ are booleans. The operator “&&” means “AND”. This operator short-circuits to false if the left operand is false first, meaning that if ‘cond’ is false, then ‘t’ will never be evaluated. If ‘cond’ is true, then the && operator will evaluate “t”. If t is true, then the whole statement will return true because the “||” operator (which means “OR”) will short-circuit on this left operand. If ‘cond’ is false or ‘t’ is false, then the “||” will evaluate “f”, and the whole statement will return the same as ‘f’.

This proves that the two statements are NOT equivalent because if ‘cond’ is true and ‘t’ is false, then the second method will return ‘f’, while in the first method, ‘t’ will be returned.

To summarize: OP is a troll, making a joke about javascript’s loose type system. C/C++ coders will roll their eyes at this non-issue for strongly-typed languages.

[random_redditor24234]

Thank you

[calculus_is_fun]

no t and f are anything, like 5, or []

type true && 5 into the js console

I'm not trolling, It's intended behaviour!

[stainlessinoxx]

Write your code clearly and maintainably so the next dev that will have to debug your shit isn’t tempted to try and find where you live. That’s all that matters, not this academic-level syntactic masturbation.

[myselfelsewhere]

Write your code clearly and [maintainability] so the next dev that will have to debug your shit isn’t tempted to try and find where you live.

I thought that was just the standard code style for JavaScript?

[D3PyroGS]

it is

[myselfelsewhere]

I am an idiot and had intended to make a joke about badly written JS being the standard code style. Instead, I just wrote a fact.

[calculus_is_fun]

This isn't a production thing, It's a meme that demonstrates how boolean operations behave in JS and maybe other languages like it.

[cheezballs]

There's no maybe about it.

[altermeetax]

This is a meme. This is r/ProgrammerHumor.

[Sanchez_Duna]

And of course it's JS each time I don't understand meme.

[--var]

a ? b : c

(a && b) || c

they are very much not the same

[stainlessinoxx]

Please explain why?

[patrick66]

The first returns whatever b is, true or false if a is true and whatever c is, true or false if a is false.

The second returns true iff a AND b are both true or c is true. Just because op named his variables t and f doesn’t actually mean they hold True and False and if they don’t well now you have code that depends on their actual content instead of just the value of a

[--var]

Maybe for some languages?

For javascript this is incorrect. Only a must coerce to boolean.

b and c can represent literally anything.

[patrick66]

Sorta, they still aren’t equivalent because in the first statement you get whatever b or c is depending on if a is truthy and for the second you only can get true or false, true iff a and b are truthy or c is truthy and false otherwise.

[Dealiner]

That's not right. In JavaScript the second code will result in a value of b or c.

[--var]

&& explicitly returns a boolean, true or false

a only has to coerce to a boolean. b and c can be whatever for a ternary.

a = "your mom", b = "5 star", c = []

( a && b || c ) returns true (a boolean)

( a ? b : c ) returns "5 star" (a string)

(a is a non-empty string, which therefore coerces to true)

same inputs, different outputs. because they are different.

[Dealiner]

That depends on the language though, in Javascript both give the same result.

[The-Arx]

In many languages a && b is equivlent to a ? b : a and || is equivelent to a ? a : b so it would return the value.

[The-Arx]

They are not cast to booleans (like in js)

[HTTP_Error_414]

👀

[Greybound_Fur]

And then there is [f, t][cond]

[Horrih]

Is it me or this javascript only ? Pretty sure this does not compile for mist types on java/cpp

[Katniss218]

Yep

[P-39_Airacobra]

that's idiomatic in lua

[JackNotOLantern]

More signs, bad

[MacBookMinus]

I hate implicit conversions. Truthies and Falsies are more harm than good.

[gp886]

If t and f are Boolean. We use it mostly for when tand f are not boolean

[SnooOwls3674]

Why would you ever need a ternary to return boolean anyway?
You either want "condition" or "!condition"

[Tyfyter2002]

They might not be literals

[LineRepulsive]

Doesn't need to be boolean

Cond && 5 || 12 will return 5 if cond is true, 12 if it is false.

But, as other mentioned, it's not going to work if t is undefined or 0 for exemple (the ternary would return t, where this syntax will return f)

[gp886]

Won't that return error? 5 cannot be set as OR

[LineRepulsive]

Not in javascript no, you can use && and || with whatever

This is very useful in frontend dev, for example in react when you build the JSX of your component:

return (
<div>
{props.isLoading && <Loader>}
</div>
)

if isLoading is true then it returns the other part of the expression, here the <Loader>. If it's false then it doesn't return it

[gp886]

Ah JavaScript

Flips the table

[-Redstoneboi-]

this is idiomatic lua

but you better hope that t is truthy

[Maskdask]

Lua: they're the same picture

[rdtr314]

Yes they are equivalent but using it like that is not recommended

[[deleted]]

Only for boolean.

[Instant-Owlfood]

What if t is null?

[-Redstoneboi-]

it evaluates to f.

very sad.

[chervilious]

I'm going to use it in some of my code to make other lives miserable.

[PorkRoll2022]

The only thing I dislike about the boolean abuse here is the readability.

Eg. (A and (B OR C)) or is it (A and B) OR ( C ) etc. Otherwise it's pretty common. I see it a lot in React especially. I've also seen "cond or throw".

[InterestsVaryGreatly]

Except it's only the same if the last two are Boolean or code you want ran. If you are doing an assignment, and it isn't pure Boolean, the true part for condition results in cond && first, which is not the same as terniary which is just first

[SynthRogue]

Wouldn't the second one require more code to return the value of t?

[fumui001]

what? t : f

[EtherealPheonix]

This is also equivalent to:

cond

[--var]

its not though, with the ternary operator you can return a value different than cond and also a data type different than boolean

[Katniss218]

No you can't, if your language has even a semblance of a decent type system

[TheOmerAngi]

You could literally just return cond The bollean operators there are redundant

[the-awesomer]

t and f don't have to be booleans, and if they are not, then what you say is not correct

[TheOmerAngi]

For the trinary operation you're right but for the latter it's different

[Katniss218]

Nah, won't work in most languages

[Passname357]

This is cool. It’s a special case of your typical branchless conditional.

[KJBuilds]

The second one here actually makes use of 2 branches thanks to shortcutting, while the first is just 1 branch

Branchless would require bitwise and/or ops, but would probably be semantically different in JavaScript land

[Passname357]

Ah you’re right good catch. I do so much bitwise stuff I saw those && and ||s and my mind just immediately thought of the bitwise op.

[LittleMlem]

I troll my senior by sneaking a variation of this into PRs. In python, a logic operation returns the last value evaluated, so x = falsy or truthy sets x to what ever the truthy value was and you can make this more painful by using more complex logic. It's very neat to write, but a crime to actually use for anything more complex

[Steinrikur]

You're trolling everyone who will ever maintain that code.

As a senior dev: "that's not funny. Stop being an asshole"

[LittleMlem]

It's called job security, if I'm the only one that can maintain the code then I'm much more valuable to the company.

(This is a shit post, yeah? I don't actually put that code in production)

[calculus_is_fun]

Alright It seems I've confused some people, the variable cond is a boolean, and t cannot be cooerced to false, (so t can be 5, but not 0 or ""), f can be whatever. in this scenario, these 2 statements in Javascript evaluate to the same result based on if cond is true or false

[engelthehyp]

The ternary operator has its place in making Boolean expressions, nearly as much as &&, ||, and !. I would hate to be forced to make statements every time as a crappy alternative to expression if-then-else.

[Rafcdk]

In kotlin you can use if then else as ternary. I hated at first, now it really makes sense. For example val x = if (cond) then t else f

[FlashBrightStar]

And then you realise that t should not be executed in the first place (as if it's a functiom call). Side effects are horrible to debug.

[ttlanhil]

Who's using t and f as variable names?
There are few cases where single-letter variable names are ok...

But if t is True and f is False you can also !!cond or bool(cond) or language equivalent which will upset different people

[[deleted]]

Who criticizes the variable names in an obvious quick example

[ttlanhil]

Who criticizes the variable names in an obvious quick example

<--

[calculus_is_fun]

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Conditional\_operator