Tracking Issue for lazy_get

[ChayimFriedman2]

Feature gate: #![feature(lazy_get)]

This is a tracking issue for LazyCell/Lock::get[_mut](), allowing you to extract a reference from a Lazy only if it is initialized, approved in ACP rust-lang/libs-team#429.

Public API

impl<T, F> core::cell::LazyCell<T, F> {
    pub fn get(this: &Self) -> Option<&T>;
    pub fn get_mut(this: &mut Self) -> Option<&mut T>;
    pub fn force_mut(this: &mut Self) -> &mut T;
}
impl<T, F> std::sync::LazyLock<T, F> {
    pub fn get(this: &Self) -> Option<&T>;
    pub fn get_mut(this: &mut Self) -> Option<&mut T>;
    pub fn force_mut(this: &mut Self) -> &mut T;
}

Steps / History

• ACP: LazyLock/Cell get_mut() and DerefMut libs-team#429
• Implementation:
  • Implement ACP 429: add LazyCell/Lock::get[_mut](), DerefMut and force_mut() #129334
  • Implement ACP 429: add Lazy{Cell,Lock}::get[_mut] and force_mut #130476
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• None yet.

Footnotes

1. https://std-dev-guide.rust-lang.org/feature-lifecycle/stabilization.html ↩