Feature gate: #![feature(option_reduce)]

This is a tracking issue for Option::reduce, which combines two Options into one if both are Some, otherwise choosing the one that's Some or returning None.

ACP: rust-lang/libs-team#609

Public API

impl<T> Option<T> { fn reduce<U, R, F>(self, other: Option<U>, f: F) -> Option<R> where T: Into<R>, U: Into<R>, F: FnOnce(T, U) -> R, { match (self, other) { (Some(a), Some(b)) => Some(f(a, b)), (Some(a), _) => Some(a.into()), (_, Some(b)) => Some(b.into()), _ => None, } } }

Steps / History

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

• Implementation: add Option::reduce #144274
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• Will this cause inference problems? ACP: Add Option::reduce libs-team#609 (comment)