do bounds

TL;DR

Design axioms

• Twiddle const is where Rust jumps the shark
  • Therefore we use do

Default trait and impl

Equivalent of default trait and impl:

#![allow(unused)]
fn main() {
const trait Default {
    fn default() -> Self;
}

struct Wrapper<T> {
    value: T
}

impl<T> const Default for Wrapper<T>
where
    T: const Default,
{
    const fn default() -> Self {
        Wrapper {
            value: T::default()
        }
    }
}

const fn get_me<T>(x: Option<Wrapper<T>>) -> Wrapper<T>
where
    T: do Default,
{
    match x {
        None => <Wrapper<T>>::default(), // <-- do we need something here?
        Some(v) => v,
    }
}
}