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diff --git a/third_party/rust/inherent/README.md b/third_party/rust/inherent/README.md new file mode 100644 index 0000000000..102abab63e --- /dev/null +++ b/third_party/rust/inherent/README.md @@ -0,0 +1,104 @@ +\#\[inherent\] +============== + +[<img alt="github" src="https://img.shields.io/badge/github-dtolnay/inherent-8da0cb?style=for-the-badge&labelColor=555555&logo=github" height="20">](https://github.com/dtolnay/inherent) +[<img alt="crates.io" src="https://img.shields.io/crates/v/inherent.svg?style=for-the-badge&color=fc8d62&logo=rust" height="20">](https://crates.io/crates/inherent) +[<img alt="docs.rs" src="https://img.shields.io/badge/docs.rs-inherent-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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" height="20">](https://docs.rs/inherent) +[<img alt="build status" src="https://img.shields.io/github/workflow/status/dtolnay/inherent/CI/master?style=for-the-badge" height="20">](https://github.com/dtolnay/inherent/actions?query=branch%3Amaster) + +This crate provides an attribute macro to make trait methods callable without +the trait in scope. + +```toml +[dependencies] +inherent = "0.1" +``` + +## Example + +```rust +mod types { + use inherent::inherent; + + trait Trait { + fn f(self); + } + + pub struct Struct; + + #[inherent(pub)] + impl Trait for Struct { + fn f(self) {} + } +} + +fn main() { + // types::Trait is not in scope, but method can be called. + types::Struct.f(); +} +``` + +Without the `inherent` macro on the trait impl, this would have failed with the +following error: + +```console +error[E0599]: no method named `f` found for type `types::Struct` in the current scope + --> src/main.rs:18:19 + | +8 | pub struct Struct; + | ------------------ method `f` not found for this +... +18 | types::Struct.f(); + | ^ + | + = help: items from traits can only be used if the trait is implemented and in scope + = note: the following trait defines an item `f`, perhaps you need to implement it: + candidate #1: `types::Trait` +``` + +The `inherent` macro expands to inherent methods on the `Self` type of the trait +impl that forward to the trait methods. In the case above, the generated code +would be: + +```rust +impl Struct { + pub fn f(self) { + <Self as Trait>::f(self) + } +} +``` + +## Visibility + +Ordinary trait methods have the same visibility as the trait or the `Self` type, +whichever's is smaller. Neither of these visibilities is knowable to the +`inherent` macro, so we simply emit all inherent methods as private by default. +A different visibility may be specified explicitly in the `inherent` macro +invocation. + +```rust +#[inherent] // private inherent methods are the default + +#[inherent(pub)] // all methods pub + +#[inherent(crate)] // all methods pub(crate) + +#[inherent(in path::to)] // all methods pub(in path::to) +``` + +<br> + +#### License + +<sup> +Licensed under either of <a href="LICENSE-APACHE">Apache License, Version +2.0</a> or <a href="LICENSE-MIT">MIT license</a> at your option. +</sup> + +<br> + +<sub> +Unless you explicitly state otherwise, any contribution intentionally submitted +for inclusion in this crate by you, as defined in the Apache-2.0 license, shall +be dual licensed as above, without any additional terms or conditions. +</sub> |