alt Hacker News> Even if you do, you now have an effective comment that tells you where to look if you ever get suspicious behavior.
By the time suspicious behavior happens, isn’t it kind of a critical inflection point?
For example, the news about react and next that came out. Once the code is deployed, re-deploying (especially with a systems language that quite possibly lives on an air-gapped system with a lot of rigor about updates) means you might as well have used C, the dollar cost is the same.
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> might as well have used C, the dollar cost is the same.
When your unsafe area is small, you put a LOT of thought/testing into those small blocks. You write SAFETY comments explaining WHY it is safe (as you start with the assumption there will be dragons there). You get lots of eyeballs on them, you use automated tools like miri to test them. So no, not even in the same stratosphere as "might as well have used C". Your probability of success vastly higher. A good Rust programmer uses unsafe judiciously, where as a C programmer barely blinks as they need ensure every single snippet of their code is safe, which in a large program, is an impossible task.
As an aside, having written a lot of C, the ecosystem and modern constructs available in Rust make writing large scale programs much easier, and that isn't even considering the memory safety aspect I discuss above.
This just skips the:
> First, if you aren't writing device drivers/kernels or something very low level there is a high probability your program will have zero unsafe usages in it.
from the original comment. Meanwhile all C code is implicitly “unsafe”. Rust at least makes it explicit!
But even if you ignore memory safety issues bypassed by unsafe, Rust forces you to handle errors, it doesn’t let you blow up on null pointers with no compiler protection, it allows you to represent your data exhaustively with sum types, etc etc etc
Are you with a straight face saying that occasionally having a safety bug in limited unsafe areas of Rust is functionally the same as having written the entire program in an unsafe language like C?
One, the dollar cost is not the same. The baseline floor of quality will be higher for a Rust program vs. a C program given equal development effort.
Second, the total possible footprint of entire classes of bugs is zero thanks to design features of Rust (the borrowck, sum types, data race prevention), except in a specifically delineated areas which often total zero in the vast majority of Rust programs.