Design meeting: Deref Patterns

[Nadrieril]

Summary

We would like to be able to match through the smart pointers of the standard library ergonomically:

let x: Option<Rc<bool>> = ...;
match x {
    Some(deref true) => ...,
    Some(x) => ...,
    None => ...,
}

There are a few design questions around this, most importantly syntax-wise. I prepared a design document with two specific proposals; I would like to discuss them.

Concrete questions I would like answered:

• Is one of these proposals something we would like to do? Any objections or unexplored possibilities?
• Should we reserve the deref keyword for edition 2024?

Background reading

• Design document (includes some links to previous discussions)
• Tracking issue for the experimental feature gate

About this issue

This issue corresponds to a lang-team design meeting proposal. It corresponds to a possible topic of discussion that may be scheduled for deeper discussion during one of our design meetings.