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1. layer8+(OP)[view] [source] 2022-10-02 16:23:09
Right. My personal opinion is that exceptions provide a better trade-off between catching bugs and still allowing the chance of graceful shutdown or recovery.
replies(2): >>Velila+s2 >>stjohn+4u
2. Velila+s2[view] [source] 2022-10-02 16:33:37
>>layer8+(OP)
In my case it wouldn't have raised an exception though, it would have just been UB.

It's not like there's not exceptions in Rust though. The error handling is thorough to a fault when it's used. Unwrap is just a shortcut to say "I know there might be bad input, I don't want to handle it right now, just let me do it and I'll accept the panic."

replies(1): >>layer8+L4
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3. layer8+L4[view] [source] [discussion] 2022-10-02 16:45:39
>>Velila+s2
By exceptions, I’m referring to languages with exceptions as a dedicated language construct with automatic stack unwinding, and preferably without UB (e.g. Java or C#). Rust doesn’t have exceptions in that sense.
replies(1): >>dureui+5i
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4. dureui+5i[view] [source] [discussion] 2022-10-02 17:58:15
>>layer8+L4
But panics in rust are pretty much exceptions though?

The differences are they are actually meant to be used for exceptional situations ("assert violated => there's a bug in this program" or "out of memory, catastrophic runtime situation") and they are not typed (rather, the panic holds a type erased payload).

Other than that, it performs unwinding without UB, and is catchable[0]. I'm not seeing the technical difference?

[0]: https://doc.rust-lang.org/std/panic/fn.catch_unwind.html

replies(1): >>layer8+yk
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5. layer8+yk[view] [source] [discussion] 2022-10-02 18:13:46
>>dureui+5i
You’re probably right now that I’ve read up on it, I wasn’t previously aware of catch_unwind.
replies(1): >>dureui+rl
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6. dureui+rl[view] [source] [discussion] 2022-10-02 18:18:57
>>layer8+yk
Glad to be of service. Note that the idiomatic error handling in rust is still Result based rather than panic/catch_unwind based.

Nevertheless a long living application like, e.g., a webserver will catch panics coming from its subtasks (e.g., its request handlers) via catch_unwind

7. stjohn+4u[view] [source] 2022-10-02 19:14:47
>>layer8+(OP)
exceptions would be awful in the kernel. I would be highly surprised if kernels like fuscia allow c++ exceptions.
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