From 95275658f26e0e83fb26f946e716fa5de28fe43a Mon Sep 17 00:00:00 2001 From: Taylor Cramer Date: Thu, 27 Jun 2019 16:11:46 -0700 Subject: [PATCH] Add Vec::leak --- src/liballoc/vec.rs | 34 ++++++++++++++++++++++++++++++++++ 1 file changed, 34 insertions(+) diff --git a/src/liballoc/vec.rs b/src/liballoc/vec.rs index 92fe0834dd0..c0544d7469c 100644 --- a/src/liballoc/vec.rs +++ b/src/liballoc/vec.rs @@ -1367,6 +1367,40 @@ impl Vec { self.truncate(new_len); } } + + /// Consumes and leaks the `Vec`, returning a mutable reference to the contents, + /// `&'a mut [T]`. Note that the type `T` must outlive the chosen lifetime + /// `'a`. If the type has only static references, or none at all, then this + /// may be chosen to be `'static`. + /// + /// This function is similar to the `leak` function on `Box`. + /// + /// This function is mainly useful for data that lives for the remainder of + /// the program's life. Dropping the returned reference will cause a memory + /// leak. + /// + /// # Examples + /// + /// Simple usage: + /// + /// ``` + /// #![feature(vec_leak)] + /// + /// fn main() { + /// let x = vec![1, 2, 3]; + /// let static_ref: &'static mut [usize] = Vec::leak(x); + /// static_ref[0] += 1; + /// assert_eq!(static_ref, &[2, 2, 3]); + /// } + /// ``` + #[unstable(feature = "vec_leak", issue = "62195")] + #[inline] + pub fn leak<'a>(vec: Vec) -> &'a mut [T] + where + T: 'a // Technically not needed, but kept to be explicit. + { + Box::leak(vec.into_boxed_slice()) + } } impl Vec {