Tracking Issue for Vec::pop_if

[avandesa]

Feature gate: #![feature(vec_pop_if)]

This feature adds the Vec::pop_if method, which takes a predicate, evaluates it with the last element in the Vec if present, and returns the item if the predicate returns true. This makes it possible to conditionally remove the last element without the use of unwrap.

Public API

// core::magic

impl<T> Vec<T> {
    pub fn pop_if<F>(&mut self, f: F) -> Option<T>
        where F: FnOnce(&mut T) -> bool;
}

Steps / History

• ACP: pop_if or Entry/Peek-like API for Vec and VecDeque libs-team#208
• Implementation: Implement Vec::pop_if #123107
• Final comment period (FCP)¹
• Stabilization PR

Unresolved Questions

• Do we want a VecDeque::pop_front_if and VecDeque::pop_back_if API under this as well?

Footnotes

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