Snap for 7127838 from 58d8acdf2aee3296207b990546f9af01d1ab0071 to s-keystone-qcom-release

Change-Id: Ie530f55a4c4834730c26c2eb02f9034991a451e9
tree: b4a59a0bf295d7cc3837dd372b5068cb95023fc6
  1. examples/
  2. patches/
  3. src/
  4. tests/
  5. .cargo_vcs_info.json
  6. .clippy.toml
  7. .editorconfig
  8. .gitattributes
  9. .gitignore
  10. .rustfmt.toml
  11. Android.bp
  12. Cargo.toml
  13. Cargo.toml.orig
  14. CHANGELOG.md
  15. LICENSE-APACHE
  16. LICENSE-MIT
  17. METADATA
  18. MODULE_LICENSE_APACHE2
  19. OWNERS
  20. README.md
  21. TEST_MAPPING
README.md

pin-project

crates.io docs.rs license rustc build status

A crate for safe and ergonomic pin-projection.

Usage

Add this to your Cargo.toml:

[dependencies]
pin-project = "1"

Compiler support: requires rustc 1.37+

Examples

#[pin_project] attribute creates projection types covering all the fields of struct or enum.

use pin_project::pin_project;
use std::pin::Pin;

#[pin_project]
struct Struct<T, U> {
    #[pin]
    pinned: T,
    unpinned: U,
}

impl<T, U> Struct<T, U> {
    fn method(self: Pin<&mut Self>) {
        let this = self.project();
        let _: Pin<&mut T> = this.pinned; // Pinned reference to the field
        let _: &mut U = this.unpinned; // Normal reference to the field
    }
}

code like this will be generated

To use #[pin_project] on enums, you need to name the projection type returned from the method.

use pin_project::pin_project;
use std::pin::Pin;

#[pin_project(project = EnumProj)]
enum Enum<T, U> {
    Pinned(#[pin] T),
    Unpinned(U),
}

impl<T, U> Enum<T, U> {
    fn method(self: Pin<&mut Self>) {
        match self.project() {
            EnumProj::Pinned(x) => {
                let _: Pin<&mut T> = x;
            }
            EnumProj::Unpinned(y) => {
                let _: &mut U = y;
            }
        }
    }
}

code like this will be generated

See documentation for more details, and see examples directory for more examples and generated code.

Related Projects

  • pin-project-lite: A lightweight version of pin-project written with declarative macros.

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.