Mirrors/rust
1
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2026-05-28 20:16:58 +03:00
Code Issues Packages Projects Releases Wiki Activity

remove unstable book entry for feature(trait_upcasting)

Browse Source
This commit is contained in:
Waffle Lapkin
2024-12-16 03:51:01 +01:00
parent e9d5d1113f
commit 9e6d0b3700
1 changed files with 0 additions and 26 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/doc/unstable-book/src/language-features/trait-upcasting.md
-26
View File
@@ -1,26 +0,0 @@
# `trait_upcasting`
The tracking issue for this feature is: [#65991]
[#65991]: https://github.com/rust-lang/rust/issues/65991
------------------------
The `trait_upcasting` feature adds support for trait upcasting coercion. This allows a
trait object of type `dyn Bar` to be cast to a trait object of type `dyn Foo`
so long as `Bar: Foo`.
```rust,edition2018
#![feature(trait_upcasting)]
trait Foo {}
trait Bar: Foo {}
impl Foo for i32 {}
impl<T: Foo + ?Sized> Bar for T {}
let bar: &dyn Bar = &123;
let foo: &dyn Foo = bar;
```