Feature gate: #![feature(option_get_or_try_insert_with)]

This is a tracking issue for the Option::get_or_try_insert_with method

This method offers a convenient way of caching fallible operations, similar to OnceLock::get_or_try_init.

Public API

// core::option

impl Option {

use std::ops::{Residual, Try};
pub fn try_get_or_insert_with<'a, R, F>(
    &'a mut self,
    f: F,
) -> <R::Residual as Residual<&'a mut T>>::TryType
where
    F: FnOnce() -> R,
    R: Try<Output = T, Residual: Residual<&'a mut T>>;
}

Steps / History

(Remember to update the S-tracking-* label when checking boxes.)

• ACP Accepted Option::try_get_or_insert_with libs-team#577
• Implementation: core: add Option::get_or_try_insert_with #143650
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• None yet.