Hi folks! When I'm trying to convince my friends in the low-level, high-performance software community to learn Rust, I frequently find people bouncing off the high-level nature of the tutorials. I think part of the problem is that Rust introductions tend to present unsafe like an afterthought, or …

"safe", "sound" whatever. Nobody outside of mathematics knows if that is some technically defined meaning or just casual mathematician slang. For the same reason can we avoid words like "monad", "monoid", "functor" when talking about Rust? At the end of the day the source code is mechanically chec…

[image] ZiCog: That does not mean it is actually unsafe. It means you have to trust a human rather than the compiler. It's that specific difference that we're trying to capture in a safe/sound distinction. Even if casual usage of the terms is casual, it definitely helps if written material co…

I feel that having a distinction between "this requires an unsafe block" and "this is undefined behaviour" is quite important, and unsafe vs unsound has served this purpose quite nicely for me.

I'm not a native English speaker, and "sound" was part of my non-technical vocabulary meaning exactly what you want to mean by it. So I think its non-technical meaning is specific enough to use it in Rust tutorials trying to avoid technical jargon from math and logic.

[image] cbiffle: I didn't intend jargon as a value judgment Me neither: "folklore" or "pathological" are examples of mathematical jargon, without value judgment :slight_smile: Update 2019-12-24. Hoping to clarify a bit: "corner case" is jargon, "abstract class" is a term.

I think everyone here is making this more complicated than it has to be. Undefined behavior (UB) can be expressed simply by stating that code behaves undefined and defined behavior can simply be referred to as code behaving defined. There's no reason to say unsafe (that means you're taking a risk, n…

Often I will use the phrases "undefined behaviour" and "not undefined behaviour", because I feel that the word "defined" is awkward, because it clashes with a different use, namely the behaviour defined by the documentation of the library.

That's where the terms specified and unspecified behavior come in.

I think the thing we've learned here is that terminology is hard and often vague, as people prefer different terms, but we shouldn't derail discussion of this (awesome!) resource further to bikeshed over terminology.

Learn Rust the Dangerous Way - the unsafe-first tutorial

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alice December 21, 2019, 7:52pm 39

Unsoundness is what happens when unsafety goes wrong.

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Learn Rust the Dangerous Way - the unsafe-first tutorial

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