mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rollup merge of #81562 - the8472:improve-inplaceiterable-docs, r=sfackler

Browse Source 
Clarify that InPlaceIterable guarantees extend to all advancing iterator methods.

A documentation update that should answer a question that came up in [this zulip discussion](https://rust-lang.zulipchat.com/#narrow/stream/219381-t-libs/topic/Safety.20guarantees.20of.20InPlaceIterable/near/223743336)

CC `@SkiFire13`
This commit is contained in:
Jonas Schievink 2021-01-31 01:47:46 +01:00 committed by GitHub
commit 709710564a
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
1 changed files with 5 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
library/core/src/iter/traits/marker.rs
View File

@ -43,12 +43,14 @@ unsafe impl<I: TrustedLen + ?Sized> TrustedLen for &mut I {}
/// An iterator that when yielding an item will have taken at least one element
/// from its underlying [`SourceIter`].
///
/// Calling [`next()`] guarantees that at least one value of the iterator's underlying source
/// has been moved out and the result of the iterator chain could be inserted in its place,
/// assuming structural constraints of the source allow such an insertion.
/// Calling any method that advances the iterator, e.g. [`next()`] or [`try_fold()`],
/// guarantees that for each step at least one value of the iterator's underlying source
/// has been moved out and the result of the iterator chain could be inserted
/// in its place, assuming structural constraints of the source allow such an insertion.
/// In other words this trait indicates that an iterator pipeline can be collected in place.
///
/// [`SourceIter`]: crate::iter::SourceIter
/// [`next()`]: Iterator::next
/// [`try_fold()`]: Iterator::try_fold
#[unstable(issue = "none", feature = "inplace_iteration")]
pub unsafe trait InPlaceIterable: Iterator {}