This doesn't seem that unreasonable.

enum FooBar {
    Foo,
    Bar
}

impl Default for FooBar {
    fn default() -> Self {
        Self::Foo
    }
}

However, it doesn't work. That's not so bad, but the error message is very unintuitive.

error: no associated item named `Foo` found for type 'hallo::salut::sunt_eu::un_haiduc::FooBar` in the current scope

I can see FooBar::Foo, it's right there. Telling me I can't use Self like this would be fine, but as it stands it's ludicrous.