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by peeters 3891 days ago
> If you use unwrap/expect/fromJust you are explicitly acknowledging that you want it to panic if it fails.

If you use Optional.get() without Optional.isPresent(), how is that any different? It's not as nice as pattern decomposition, but it's still fundamentally the same, and on top of that, transform functions are provided so that most of the time you can do null-safe operations.

1 comments

The difference is that Optional itself can be null, and in Java everything can be null.
It can be, and it's annoying, but that's still a step forward. It's trivial for a good static checker to treat all Optional references as if they were annotated with your favorite @Nonnull annotation.
But in Java you'd never use a library that calls System.exit when it reaches an unexpected null
See my other comment: https://news.ycombinator.com/item?id=10452408

In Rust you'd rarely write a library that panics on unexpected nulls.

(Also, panic != abort, yada yada)