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Pitfalls of Safe Rust

(corrode.dev)
168 points pjmlp | 1 comments | 04 Apr 25 17:55 UTC | HN request time: 0.205s | source
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quotemstr ◴[06 Apr 25 18:42 UTC] No.43603841[source]▶
Some of this advice is wrongheaded. Consider array indexing: usually, an out of bounds access indicates a logic error and should fail fast to abort the problem so it doesn't go further off the rails. Encouraging people to use try-things everywhere just encourage them to paper over logic bugs and leads to less reliable software in the end. Every generation has to learn this lesson anew through pain.
replies(2): >>43604025 #>>43604088 #
1. hansvm ◴[06 Apr 25 19:12 UTC] No.43604088[source]▶
Try-things have the benefit of accurately representing the thing you're describing. Leave it to the caller to decide whether to panic or resize the data structure or whatever.

That's also not the only choice in the design space for correct array accesses. Instead of indices being raw integers, you can use tagged types (in Rust, probably using lifetimes as the mechanism if you had to piggy back on existing features, but that's an implementation detail) and generate safe, tagged indices which allow safe access without having to bounds check on access.

However you do it, the point is to not lie about what you're actually doing and invoke a panic-handler-something as a cludgy way of working around the language.