Bring enum variants in scope for patterns

19

Would this only apply to the top-level scrutinee? I see matching on Options of enums relatively commonly, so would you also be able to write

match Some(Foo::Bar) {
    Some(Bar) => {}
    Some(Baz) => {}
    Some(Quux) => {}
    None => {}
}

It would also be useful to be able to do the same thing for manual struct+associated const enums as well, you can't even currently use them to bring the consts into scope :frowning: (though that is likely much more controversial)

#[derive(PartialEq, Eq)]
struct Foo(u8);

impl Foo {
    const BAR: Self = Self(0);
    const BAZ: Self = Self(1);
    const QUUX: Self = Self(2);
}

match Foo::BAR {
    BAR => {}
    BAZ => {}
    QUUX => {}
    _ => {}
}
2 Likes