nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2024-11-25 16:24:46 +00:00
Code Issues Packages Projects Releases Wiki Activity

Explicitly document how Send and Sync relate to references

Browse Source 
Some of these relations were already mentioned in the text, but that
Send is implemented for &mut impl Send was not mentioned,
neither did the docs list when &T is Sync.
This commit is contained in:
est31 2023-05-01 16:39:54 +02:00
parent f2eb9f85b9
commit 09c50a0ae3
1 changed files with 6 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
library/core/src/marker.rs
View File

@ -24,7 +24,7 @@ use crate::hash::Hasher;
/// operations. Its cousin [`sync::Arc`][arc] does use atomic operations (incurring /// operations. Its cousin [`sync::Arc`][arc] does use atomic operations (incurring
/// some overhead) and thus is `Send`. /// some overhead) and thus is `Send`.
/// ///
/// See [the Nomicon](../../nomicon/send-and-sync.html) for more details. /// See [the Nomicon](../../nomicon/send-and-sync.html) and the [`Sync`] trait for more details.
/// ///
/// [`Rc`]: ../../std/rc/struct.Rc.html /// [`Rc`]: ../../std/rc/struct.Rc.html
/// [arc]: ../../std/sync/struct.Arc.html /// [arc]: ../../std/sync/struct.Arc.html
@ -426,6 +426,11 @@ pub macro Copy($item:item) {
/// becomes read-only, as if it were a `& &T`. Hence there is no risk /// becomes read-only, as if it were a `& &T`. Hence there is no risk
/// of a data race. /// of a data race.
/// ///
/// A shorter overview of how [`Sync`] and [`Send`] relate to referencing:
/// * `&T` is [`Send`] if and only if `T` is [`Sync`]
/// * `&mut T` is [`Send`] if and only if `T` is [`Send`]
/// * `&T` and `&mut T` are [`Sync`] if and only if `T` is [`Sync`]
///
/// Types that are not `Sync` are those that have "interior /// Types that are not `Sync` are those that have "interior
/// mutability" in a non-thread-safe form, such as [`Cell`][cell] /// mutability" in a non-thread-safe form, such as [`Cell`][cell]
/// and [`RefCell`][refcell]. These types allow for mutation of /// and [`RefCell`][refcell]. These types allow for mutation of