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Comment by postflopclarity | Hacker News Reader

improving, still not perfect. it was true then, and is even more true now, that a large fraction of "correctness bugs" (maybe even the majority) arise from `OffsetArrays.jl`, so a simple solution besides "avoid Julia" is "avoid that package"

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The greater issue that there is still no way to prevent those types of composability bugs.

sure there are ways. they're just not employed as diligently as they should be. that's more of a social problem than a technical problem.

The simplest approach is to always read the interface of packages one wants to use, and if one isn't provided look at the code / open an issue to interact with the developers about their input assumptions. One should also make tests to ensure the interface behaves in the expected manner when working with your code.

Using this approach since 2017 I've never really encountered the types of issues mentioned in Yuri's blog post. The biggest issue I've had is if some user-package makes a change that is effectively breaking but they don't flag it the associated release as breaking. But this isn't really a Julia issue so much as a user-space issue, and can happen in any language when relying on others' libraries.

It doesn't happen so frequently in practice, which is maybe why it's not felt equally by everyone in the community. I've followed some discussions on this topic and the current solution is, as you say, to place the onus entirely on the user. There is another faction that wants to support the user through the IDE to warn them of errors they might be making, and others that want to implement formal specifications that catch the errors during specifications. It's not an easy problem to fix and therefore the "simplest approach" as you describe remains the leading solution.

It baffles me that they dug this hole in the first place. I have feelings on the zero-indexing vs one-indexing debate, but at the end of the day you can write correct code in either, as long as you know which one you're using.

But Julia fucked it up to where it's not clear what you're using, and library writers don't know which one has been passed! It's insane. They chose style over consistency and correctness and it's caused years of suffering.

Technically you don't need to know what array indexing is being used if you iterate using firstindex(arr):lastindex(arr). AFAIK the issue was that this wasn't consistently done across the Julia ecosystem including parts of the standard library at the time. No clue as to whether this still holds true, but I don't worry about it because I don't use OffsetArrays.

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