[eeZah7Ux]

> Panicking is, in many ways, the best-case scenario for code that contains a bug.

The very opposite: it's among the worst behaviors, short of creating a vulnerability.

From any modern languages we should expect an exception to be raised.

[mbrubeck]

"Panic" is essentially the Rust name for exceptions. They are even implemented the same as C++ exceptions in terms of codegen. The real differences are cultural rather than technical, as I touch on in this thread:

https://users.rust-lang.org/t/c-pitfalls-hard-to-avoid-that-...

[eeZah7Ux]

No, it does not have the same semantics of exceptions.

[MaulingMonkey]

Care to give an example or two?

Rust panics, like C++ exceptions, can unwind the stack and invoke Drop/destructors.

Rust panics, like C++ exceptions, can be caught, inspected, and recovered from - using std::panic::catch_unwind instead of try/catch statements.

Rust panics can be rethrown with std::panic::resume_unwind, just as you can rethrow C++ exceptions with "throw;".

Rust panic payloads can be a wide variety of types - anything that conforms to "dyn Any + Send + 'static" - just as you can throw a wide variety of exception types in C++. While Rust panic payloads are typically a &str or String, they're not limited to that, and C++ lets you throw C-strings or std::string too.

Unhandled Rust panics terminate the application, unhandled C++ exceptions std::terminate (which by default invokes abort) the application.

It's discouraged to use Rust panics for general control flow, but that's cultural rather than semantic - you can totally use them for control flow. Nothing is stopping you, except hopefully your code reviewer.

Rust panics can be configured to abort instead of unwinding, but that's just a cleaner alternative to C++ compilers typically giving you the option to disable exceptions entirely - and it's not unheard of for a C++ library to wrap exception throwing with macros, such that these can abort instead when built without exception handling support.