this post was submitted on 09 Jul 2023
614 points (93.9% liked)
Programmer Humor
31812 readers
598 users here now
Post funny things about programming here! (Or just rant about your favourite programming language.)
Rules:
- Posts must be relevant to programming, programmers, or computer science.
- No NSFW content.
- Jokes must be in good taste. No hate speech, bigotry, etc.
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
I think it's a convention taken from math notation conventions.
I is short for "index" for a traditional for loop for mapping over an array and looking up by index. J comes after I and is used for nested loops so it doesn't shadow the outer I.
Is it for “index” or “iterator”?
yes
index and jindex
jndex
I believe index for the classical need to iterate through an array. E.g.
for (i = 0; I <= arr.length; i++) { var thing = arr[i] ... }
So to me it stands for "index" for array lookup.
Before map and iterators were implemented in a lot of languages, this was the defacto way to iterate a list. At least this is how I learned it in java/c back in the day. Nowadays I think most OOP languages including java have implemented the "for ... in ..." Syntax or similar which deprecates this convention.