this post was submitted on 01 Sep 2023
339 points (96.2% liked)

Programming

17534 readers
246 users here now

Welcome to the main community in programming.dev! Feel free to post anything relating to programming here!

Cross posting is strongly encouraged in the instance. If you feel your post or another person's post makes sense in another community cross post into it.

Hope you enjoy the instance!

Rules

Rules

  • Follow the programming.dev instance rules
  • Keep content related to programming in some way
  • If you're posting long videos try to add in some form of tldr for those who don't want to watch videos

Wormhole

Follow the wormhole through a path of communities [email protected]

founded 2 years ago
MODERATORS
snowe
Ategon
[email protected]
339
What are your programming hot takes? (lemmy.ml)
submitted 1 year ago by [email protected] to c/programming
897 comments fedilink hide all child comments
you are viewing a single comment's thread
view the rest of the comments
[–] hellishharlot 31 points 1 year ago (33 children)

Using single character variable names is always bad practice

[–] [email protected] 12 points 1 year ago* (last edited 1 year ago) (14 children)

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

[–] hellishharlot 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

[–] [email protected] 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 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
}
[–] [email protected] 1 points 1 year ago (1 children)

The world where the convention is i

[–] hellishharlot 1 points 1 year ago (1 children)

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

[–] [email protected] 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.

[–] [email protected] 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?

[–] [email protected] 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 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?

[–] [email protected] 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 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.

[–] [email protected] 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.

load more comments (11 replies)
load more comments (29 replies)