diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/doc/rustc-dev-guide/src/stability.md | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/src/doc/rustc-dev-guide/src/stability.md b/src/doc/rustc-dev-guide/src/stability.md index c26d34273d7..3c4c65fdd5a 100644 --- a/src/doc/rustc-dev-guide/src/stability.md +++ b/src/doc/rustc-dev-guide/src/stability.md @@ -182,6 +182,11 @@ of the standard library raises it to a warning with `#![warn(deprecated_in_future)]`. ## unstable_feature_bound -The `#[unstable_feature_bound(foo)]` attribute can be used together with `#[unstable]` attribute to mark an `impl` of stable type and stable trait as unstable. In std/core, an item annotated with `#[unstable_feature_bound(foo)]` can only be used by another item that is also annotated with `#[unstable_feature_bound(foo)]`. Outside of std/core, using an item with `#[unstable_feature_bound(foo)]` requires the feature to be enabled with `#![feature(foo)]` attribute on the crate. Currently, only `impl`s and free functions can be annotated with `#[unstable_feature_bound]`. +The `#[unstable_feature_bound(foo)]` attribute can be used together with `#[unstable]` attribute to mark an `impl` of stable type and stable trait as unstable. In std/core, an item annotated with `#[unstable_feature_bound(foo)]` can only be used by another item that is also annotated with `#[unstable_feature_bound(foo)]`. Outside of std/core, using an item with `#[unstable_feature_bound(foo)]` requires the feature to be enabled with `#![feature(foo)]` attribute on the crate. + +Currently, the items that can be annotated with `#[unstable_feature_bound]` are: +- `impl` +- free function +- trait [blog]: https://www.ralfj.de/blog/2018/07/19/const.html |