Too Many Questions

lib.rs

#![feature(try_trait_v2)]

use core::ops::{ControlFlow, FromResidual, Try};

#[allow(dead_code)]
fn questions(x: Undemystifiable) -> Undemystifiable {
    x????????????????????????????????????????????????????????????????
}

struct Undemystifiable;

impl Try for Undemystifiable {
    type Output = Self;
    type Residual = Self;

    fn from_output(output: Self::Output) -> Self {
        output
    }

    fn branch(self) -> ControlFlow<Self::Residual, Self::Output> {
        ControlFlow::Continue(Self)
    }
}

impl FromResidual<Undemystifiable> for Undemystifiable {
    fn from_residual(residual: Undemystifiable) -> Self {
        residual
    }
}