Feature gate: #![feature(once_cell_get_mut)]

This is a tracking issue for

• OnceCell::get_mut_or_init()
• OnceCell::get_mut_or_try_init()
• OnceLock::get_mut_or_init()
• OnceLock::get_mut_or_try_init()

Public API

    pub fn get_mut_or_try_init<F, E>(&mut self, f: F) -> Result<&mut T, E>
    where
        F: FnOnce() -> Result<T, E> { ... }

    pub fn get_mut_or_init<F>(&mut self, f: F) -> &mut T
    where
        F: FnOnce() -> T { ... }

Steps / History

• ACP: Add get_mut_or_init and get_mut_or_try_init for OnceCell libs-team#294
• Implementation: impl get_mut_or_init and get_mut_or_try_init for OnceCell and OnceLock #114788
• Final comment period (FCP)
• Stabilization PR

Unresolved Questions

None yet.

Footnotes

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