• soloner@lemmy.world
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      1 year ago

      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.

        • soloner@lemmy.world
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          1 year ago

          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.