diff options
| -rw-r--r-- | src/doc/rustdoc/src/unstable-features.md | 82 |
1 files changed, 0 insertions, 82 deletions
diff --git a/src/doc/rustdoc/src/unstable-features.md b/src/doc/rustdoc/src/unstable-features.md index 4327a80cd08..a8856c2ecc7 100644 --- a/src/doc/rustdoc/src/unstable-features.md +++ b/src/doc/rustdoc/src/unstable-features.md @@ -56,88 +56,6 @@ It is also not emitted for foreign items, aliases, extern crates and imports. These features operate by extending the `#[doc]` attribute, and thus can be caught by the compiler and enabled with a `#![feature(...)]` attribute in your crate. -### `#[doc(cfg)]`: Recording what platforms or features are required for code to be present - - * Tracking issue: [#43781](https://github.com/rust-lang/rust/issues/43781) - -You can use `#[doc(cfg(...))]` to tell Rustdoc exactly which platform items appear on. -This has two effects: - -1. doctests will only run on the appropriate platforms, and -2. When Rustdoc renders documentation for that item, it will be accompanied by a banner explaining - that the item is only available on certain platforms. - -`#[doc(cfg)]` is intended to be used alongside [`#[cfg(doc)]`][cfg-doc]. -For example, `#[cfg(any(windows, doc))]` will preserve the item either on Windows or during the -documentation process. Then, adding a new attribute `#[doc(cfg(windows))]` will tell Rustdoc that -the item is supposed to be used on Windows. For example: - -```rust -#![feature(doc_cfg)] - -/// Token struct that can only be used on Windows. -#[cfg(any(windows, doc))] -#[doc(cfg(windows))] -pub struct WindowsToken; - -/// Token struct that can only be used on Unix. -#[cfg(any(unix, doc))] -#[doc(cfg(unix))] -pub struct UnixToken; - -/// Token struct that is only available with the `serde` feature -#[cfg(feature = "serde")] -#[doc(cfg(feature = "serde"))] -#[derive(serde::Deserialize)] -pub struct SerdeToken; -``` - -In this sample, the tokens will only appear on their respective platforms, but they will both appear -in documentation. - -`#[doc(cfg(...))]` was introduced to be used by the standard library and currently requires the -`#![feature(doc_cfg)]` feature gate. For more information, see [its chapter in the Unstable -Book][unstable-doc-cfg] and [its tracking issue][issue-doc-cfg]. - -### `doc_auto_cfg`: Automatically generate `#[doc(cfg)]` - - * Tracking issue: [#43781](https://github.com/rust-lang/rust/issues/43781) - -`doc_auto_cfg` is an extension to the `#[doc(cfg)]` feature. With it, you don't need to add -`#[doc(cfg(...)]` anymore unless you want to override the default behaviour. So if we take the -previous source code: - -```rust -#![feature(doc_auto_cfg)] - -/// Token struct that can only be used on Windows. -#[cfg(any(windows, doc))] -pub struct WindowsToken; - -/// Token struct that can only be used on Unix. -#[cfg(any(unix, doc))] -pub struct UnixToken; - -/// Token struct that is only available with the `serde` feature -#[cfg(feature = "serde")] -#[derive(serde::Deserialize)] -pub struct SerdeToken; -``` - -It'll render almost the same, the difference being that `doc` will also be displayed. To fix this, -you can use `doc_cfg_hide`: - -```rust -#![feature(doc_cfg_hide)] -#![doc(cfg_hide(doc))] -``` - -And `doc` won't show up anymore! - -[cfg-doc]: ./advanced-features.md -[unstable-doc-cfg]: ../unstable-book/language-features/doc-cfg.html -[issue-doc-cfg]: https://github.com/rust-lang/rust/issues/43781 - ### Adding your trait to the "Notable traits" dialog * Tracking issue: [#45040](https://github.com/rust-lang/rust/issues/45040) |