Easyway to use inherit pattern

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10

FWIW, the ambassador crate is my current favorite for this specific use case, if you want some macro-driven sugar. Any macro solution will necessarily require annotating the trait as well. ambassador emits a macro_rules! macro alongside your trait which is used to implement the actual delegation.

With ambassador, the OP example would look like

use ambassador::{delegatable_trait, Delegate};

#[delegatable_trait]
trait Interface {
    fn f1(&self);
    fn f2(&self);
}

struct Super {}
impl Interface for Super {
    fn f1(&self) {}
    fn f2(&self) {}
}

#[derive(Delegate)]
#[delegate(Interface)]
struct Sub1(Super);

(A derive macro is used because it's nicer to IDEs, since it cannot change the struct definition like a non-derive attribute macro could.)

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