Unwrap means it forces to evaluate the result as an ”ok value”. If it’s an ”error value”, it will crash. It’s a bad practice to rely on it, as it’s one of the most common ways a Rust programs can crash.

Rust offers many options to handle errors that don’t risk crashing. For example, unwrap_or_default, which means ”if it’s an error value, use the default value for this type, such as 0 for integers”

[–] Korne127@lemmy.world 16 points 1 week ago (5 children)

I mean using unwrap is not bad practice if the value is guaranteed to not be none, which can happen frequently in some applications.

[–] mobotsar@sh.itjust.works 4 points 1 week ago* (last edited 1 week ago) (3 children)

If it's guaranteed to not be None, why is it an Option?

[–] emilgardis@lemmy.ml 3 points 1 week ago

Here's a bad example but hopefully captures the why. https://play.rust-lang.org/?version=stable&mode=debug&edition=2024&gist=43d055381e7bb52569c339d4526818f4

We have a condition we know must be satisfied (the option will always be Some), but cant prove in code.

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