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Neither are true, `std:fs::remove_dir_all("/home/user/homework")` will happily compile and run, no matter if that's what you wanted or not.

Rust programs can't know what you want to do, period.

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The better phrase is that "if it compiles, then many possible Heisenbugs vanish"

https://qouteall.fun/qouteall-blog/2025/How%20to%20Avoid%20F...

They certainly know that you dont want to process garbage data from freed memory.

Soundness does not cover semantic correctness. Maybe you want to wipe $HOME.

>They certainly know that you dont want to process garbage data from freed memory.

It depends on what you mean by "freed". Can one write a custom allocator in Rust? How does one handle reading from special addresses that represent hardware? In both of these scenarios, one might read from or write to memory that is not obviously allocated.

Both of those things can be done in Rust, but not in safe Rust, you have to use unsafe APIs that don't check lifetimes at compile time. Safe Rust assumes a clear distinction between memory allocations that are still live and those that have been deallocated, and that you never want to access the latter, which of course is true for most applications.

You can indeed write custom allocators, and you can read to or write from special addresses. The former will usually, and the latter will always, require some use of `unsafe` in order to declare to the compiler: "I have verified that the rules of ownership and borrowing are respected in this block of code".

"If it compiles, then only logical bugs will make it eat your homework"

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