Tracking Issue for const bool::then{,_some} functions

[fee1-dead]

Feature gate: #![feature(const_bool_to_option)]

This is a tracking issue for const bool::then{,_some} functions.

See also #80967

Public API

// core::bool

impl bool {
    pub const fn then_some<T>(self, t: T) -> Option<T>
    where
        T: ~const Drop;

    pub const fn then<T, F>(self, f: F) -> Option<T>
    where
        F: ~const FnOnce() -> T,
        F: ~const Drop;
}

Steps / History

• Implementation: Constify bool::then{,_some} #91918
• Final comment period (FCP)
• Stabilization PR

Unresolved Questions

• None yet.

[gimbling-away]

Should this be stabilized? It doesn't seem to have had any issues since the start (Dec 2021).

[jplatte]

I don't think APIs that use ~const bounds can be stabilized yet.

[RalfJung]

This got removed by #110393.