Tracking Issue for Unlockable Guards

Feature gate: #![feature(unlockable_guards)]

This is a tracking issue for unlocking nonpoison guards temporary while only holding a mutable reference to them.

Public API

// std::sync::nonpoison::mutex

#[unstable(feature = "unlockable_guards", issue = "148568")]
#[unstable(feature = "nonpoison_mutex", issue = "134645")]
impl<T: ?Sized> MutexGuard<'_, T> {
    pub fn unlocked<F>(self: &mut Self, func: F) where F: FnOnce() -> ();
}

// std::sync::nonpoison::rwlock

#[unstable(feature = "unlockable_guards", issue = "148568")]
#[unstable(feature = "nonpoison_mutex", issue = "134645")]
impl<T: ?Sized> RwLockWriteGuard<'_, T> {
    pub fn unlocked<F>(self: &mut Self, func: F) where F: FnOnce() -> ();
}

#[unstable(feature = "unlockable_guards", issue = "148568")]
#[unstable(feature = "nonpoison_mutex", issue = "134645")]
impl<T: ?Sized> RwLockReadGuard<'_, T> {
    pub fn unlocked<F>(self: &mut Self, func: F) where F: FnOnce() -> ();
}

Steps / History

• ACP: rust-lang/libs-team#679
• Implementation: #...
• Final comment period (FCP)^1
• Stabilization PR

Unresolved Questions

• None yet.

Start with the proposed APIs under std::sync::nonpoison::mutex and std::sync::nonpoison::rwlock, then read ACP rust-lang/libs-team#679. The implementation, final comment period, and stabilization steps are still unchecked; completion requires progressing those tracked stages.