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A comment on Java 8’s new Optional type doesn't solve anything. Parent comment

Re:Java 8’s new Optional type doesn't solve anything by codygman on Monday October 26, 2015 @08:49PM (#10455496)
The definition in Rust's documentation[0] was this:

    let x: Option<&str> = None;
    assert_eq!(x.unwrap(), "air"); // fails
The equivalent Haskell if unwrap throws a panic as the docs[0] seem to imply:

    λ> fromMaybe (error "panic!") Nothing
    *** Exception: panic!
You could also do something like this if you don't mind dealing with the wrapped boolean value:

    λ> fmap (== "air") (Just "air")
    Just True
and the failure case:

    λ> fmap (== "air") (Nothing)
    Nothing
0: https://doc.rust-lang.org/std/option/enum.Option.html#method...
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Re:Java 8’s new Optional type doesn't solve anything by steveklabnik on Tuesday October 27, 2015 @08:43AM (#10457591)
Right, but it's still not unsafe. The stack unwinds, destructors get called.

And I meant some notion of 'safety', not fromMaybe/fromJust.

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