There's a common trope among people unfamiliar with rust where they assume that if you use unsafe at all, then it's just as unsafe as C and rust provided no benefit. Comparing C's approach to safety vs Rust's is like comparing an open world assumption to a closed world assumption in formal logic systems [1]. In C, you publish your api if it's possible to use correctly (open world). In Rust, you publish a safe api if it's im possible to use in correctly (closed world). Rust's key innovation here is that it enables you to build a 'bridge' from open world (unsafe) to a closed world (safe), a seemingly impossible feat that feels like somehow pairwise reducing an uncountable infinity with a countable infinity. Rust's decision to design an analogous closed-world assumption for safe code is extremely powerful, but it seems very hard for old school C programmers to wrap their head around it.
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