this post was submitted on 01 Sep 2023
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Programming

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[–] hellishharlot@programming.dev 30 points 1 year ago (10 children)

Using single character variable names is always bad practice

[–] 9point6@lemmy.world 12 points 1 year ago* (last edited 1 year ago) (3 children)

Except i right? Something like counter or index seems unconventional and unnecessarily verbose

[–] SolarMech@slrpnk.net 6 points 1 year ago

Yeah, but it's easy to overuse it. If your for loop is much longer. For a few lines I'd agree, don't bother using something longer.

Code should scream out it's intent for the reader to see. It's why you are doing something that needs to be communicated, not what you are doing. "i", "counter" or "index" all scream out what you are doing, not why. This is more important than the name being short (but for equal explanations of intent, go with the shorter name). The for loop does that already.

If you can't do that, be more precise. At the least make it "cardIndex", or "searchIndex". It makes it easier to connect the dots.

[–] hellishharlot@programming.dev 5 points 1 year ago (2 children)

Index can be useful but start looking for mapping and sorting functions. Or foreach. If you really must index, sure go use index or I if it's conventionally understood. But reading something like for I in e where p == r.status is really taxing to make sense of

[–] indepndnt@lemmy.world 2 points 1 year ago (3 children)

Honest question: is there a mapping function that handles the case where you need to loop through an iterable, and conditionally reference an item one or two steps ahead in the iterable?

[–] xigoi@lemmy.sdf.org 2 points 1 year ago* (last edited 1 year ago)

In Haskell, you could do something like map (\(thisItem, nextItem) -> …) (zip list (tail list))

[–] hellishharlot@programming.dev 2 points 1 year ago (1 children)

Not that I'm aware of but that's a condition where you're thinking with an index. What's the difference you're looking for?

[–] indepndnt@lemmy.world 1 points 1 year ago (1 children)

Something like parsing a string that could have command codes in it of varying length. So I guess the difference is, is this a 1-, 2-, or 3-character code?

I have something like this in a barcode generator and I keep trying to find a way to make it more elegant, but I keep coming back to index and offset as the simplest and most understandable approach.

[–] hellishharlot@programming.dev 1 points 1 year ago

So you could generate lists of 1, 2, and 3 character code items rather than looking at index +1 or something.

[–] drathvedro@lemm.ee 2 points 1 year ago

In js there's reduce. Something like

arr.reduce((result, currentValue, currentIndex, original) => {
if(currentIndex < original.length - 2
    && original[currentIndendex + 2] % 2 === 0 ) {
    result.push(currentValue / 2) 
} else { 
    result.push(currentValue);
}
return result;
}, []) 

This would map arr and return halved values for elements for which the element two steps ahead is even. This should be available in languages where map is present. And sorry for possible typos, writing this on mobile.

[–] 9point6@lemmy.world 2 points 1 year ago* (last edited 1 year ago) (1 children)

Oh yeah, I map, filter and reduce pretty much everywhere I can. But sometimes you need the index and i is so commonly understood to be that, I'd say it could even be less legible to deviate from that convention

[–] hellishharlot@programming.dev 2 points 1 year ago* (last edited 1 year ago) (1 children)

In what world is

for (int index = 0; index < objectToIterate; index++)
{
    // DO YO THANG
}

less coherent than

for (int i; i < objectToIterate; i++)
{
    // DO YO THANG
}
[–] 9point6@lemmy.world 1 points 1 year ago (1 children)

The world where the convention is i

[–] hellishharlot@programming.dev 1 points 1 year ago (1 children)

What's incoherent about the first one? Why is index bad beyond standards

[–] 9point6@lemmy.world 1 points 1 year ago

It's not incoherent, it just takes a tiny bit more effort to mentally parse as it's not a stereotypical for loop. Maybe it's just me, but let me try and explain

With the i example if you're familiar enough with a language, your brain will gloss over the unimportant syntax, you go straight to the comparison and then whether it's incrementing or decrementing.

With the other example, the first my brain did was notice it's not following convention, which then pushes me to read the line carefully as there is probably a reason it doesn't.

I'm not saying it's a huge difference or anything, but following code conventions like this makes things like code reviews much easier cumulatively.

[–] UnfortunateShort@lemmy.world 4 points 1 year ago

I'd say except indices in general. Just bloats every line where you need to use them. Imagine writing CUDA C++ where you regularly add and multiply stuff and every number is referenced via (usually) 1-3 indices. Horrible.

[–] anon_8675309@lemmy.world 9 points 1 year ago (1 children)

Always and never are always bad.

[–] DahGangalang@infosec.pub 2 points 1 year ago

Counter point:

Always and Never is never bad.

[–] Double_A@discuss.tchncs.de 8 points 1 year ago

Unless you are implementing some mathematical formula. Then link the paper and stick to its variables.

[–] Thoth19@lemmy.world 7 points 1 year ago (1 children)

Guess I'll have to name all of my iterators "it" instead of "I". That will fix things.

Definitely a hot take though. Bc there are definitely times when it is totally acceptable.

[–] hellishharlot@programming.dev 2 points 1 year ago (1 children)

Iter works better than I for clarity

[–] UnfortunateShort@lemmy.world 3 points 1 year ago

An iterator is commonly understood to be an object and thus something much more complex than a simple integer. This is the exact opposite of more clear.

[–] space_comrade@hexbear.net 7 points 1 year ago* (last edited 1 year ago)

Counterpoint: using anything other than 'i' as your index in a for loop in C or C++ is obnoxious as fuck.

At most I'll go with 'it' for C++ iterators.

[–] verstra@programming.dev 7 points 1 year ago (1 children)

I have a convention to correlate the size of variable scope with its name length.

If a variable is used all over the program, it will be named "response". If it is <15 lines, then it can be "res". If it is less than 3 lines, it can be only "r".

This makes reading code a bit simpler, because it makes unimportant, local vars short and unnoticeable.

[–] hellishharlot@programming.dev 7 points 1 year ago (2 children)

Why though? Intellisense helps you write out the full name. And instead of response why not call it whatever the data you're expecting to be

[–] lemmyingly@lemm.ee 2 points 1 year ago

I agree because it makes the code easier to follow in 6 months time.

[–] JuneFall@hexbear.net 1 points 1 year ago

Could you comment a couple of examples? At best some that signifiy the importance with them as verstra wrote.

[–] jvisick@programming.dev 6 points 1 year ago

Mostly agree. I’m ok with single characters in a one line / single expression lambda, but that’s the only time I’m ok with it.

[–] morrowind@lemmy.ml 4 points 1 year ago (1 children)

Sometimes you're just using it once and it's blindingly obvious what it is

[–] tryptaminev@feddit.de 4 points 1 year ago

To be fair everyone with poor documentation thinks the code is blindingly obvious when they write it.

[–] uralsolo@hexbear.net 3 points 1 year ago (1 children)

I understand this conceptually, but there's also a gremlin in my brain that wants me to make every line as short as possible.

[–] hellishharlot@programming.dev 1 points 1 year ago

Big same. Long feels complex until you go back later

[–] Chingzilla@lemmy.world 3 points 1 year ago (1 children)
[–] hellishharlot@programming.dev 1 points 1 year ago

JavaScript, TypeScript, and C# babyyyy