[J_Shelby_J]

I don’t understand why Rust even has panics if its primary goal is safety. We should be able to prove that the code has no paths that may panic ever. I’ve been looking at this all week. It’s very difficult to make a program that is guaranteed not to panic. My understanding is that the panic handler is about 300kb, and the only way to exclude it is if your code has no paths that can panic when it compiles. And after it compiles you can check the binary to see if the panic handler was included. It’s hacky.

Yes you can lint out unwraps and other panic operations, but if there was a subset of no-panic rust a large part of the issue detailed in this post goes away. But it’s frustrating working with a language that has so many operations that can, in theory, panic even if in practice they should only do so if a bit flips. Like a proving an array is non-empty or working with async. You either end up with a lot of error handling for situations which will never happen or really strange patterns like non-empty list pattern (structure with first field and then your list). Which of course ends up adding its own bloat.

[zozbot234]

> I don’t understand why Rust even has panics if its primary goal is safety. We should be able to prove that the code has no paths that may panic ever. I’ve been looking at this all week. It’s very difficult to make a program that is guaranteed not to panic.

The Rust-in-Linux folks are working on this with things like failable memory operations. It's required for their own use. Increased use of proof (such as proving that an array is non-empty) is also being slowly worked on.

[dodobirdlord]

Panicking is fairly important for ergonomics and safety. If panicking wasn’t available and execution had to proceed in all situations, recovering from a situation like memory corruption where invariants have been violated would require a lot of error handling anywhere an invariant is checked. This is exactly the sort of large amounts of error handling for situations that will almost certainly never arise than you are concerned about.

[steveklabnik]

> I don’t understand why Rust even has panics if its primary goal is safety.

Rust's goal is memory safety. Panics are perfectly memory safe.

[positron26]

The OS running the program isn't even perfect.

I tire so much of complainers who want someone else to make all their tools infallible yet want to do nothing. Let's just full-stop there. They not only want to avoid working on the tools. They prefer if the tool does everything for them, and they prefer having things done for them without bound.

Complainers want easy APIs. When the API isn't easy enough, they want easy Kubernetes containers "programmed" by YAML. When that isn't easy enough, it's all point-and-click hosted services on GCP and Amazon. You people don't want to program. You want apps. Infallable apps. You want to be consumers, fed from the sky like little birds who endeavor only never to fledge, never to fly. And you want to pay nothing for it.

The secret you people need to figure out is that the lifestyle you think is sustainable is actually a commensal relationship with people building things for you. There is no vast alliance to wrest power from corporations, to dissolve capitalism, no grass roots movement to "shake things up." There is food falling from higher in the water column from an ecosystem filled with people who do things. Those above do not have time to look down, but if they did, all they would feel is overwhelming contempt, so they only look across at the horizon.

But why do people seek to confirm comments like this? Because Rust scary. Churn on, little ant mill. Let be free any who understand the pointlessness of this performance.