#macros #attribute #pin

macro pin-project

An attribute that creates a projection struct covering all the fields

14 releases

✓ Uses Rust 2018 edition

0.3.1 Mar 2, 2019
0.3.0 Feb 20, 2019
0.2.2 Feb 20, 2019
0.1.8 Feb 2, 2019
0.1.7 Jan 19, 2019

#153 in Rust patterns

Download history 26/week @ 2019-01-05 48/week @ 2019-01-12 27/week @ 2019-01-19 2/week @ 2019-01-26 13/week @ 2019-02-02 10/week @ 2019-02-09 95/week @ 2019-02-16 20/week @ 2019-02-23

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Apache-2.0/MIT

38KB
595 lines

pin-project

Build Status version documentation license Rustc Version

An attribute that creates a projection struct covering all the fields.

Documentation

Usage

Add this to your Cargo.toml:

[dependencies]
pin-project = "0.3"

The current version of pin-project requires Rust 1.33 or later.

Examples

unsafe_project attribute creates a projection struct covering all the fields.

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

#[unsafe_project(Unpin)] // `(Unpin)` is optional (create the appropriate conditional Unpin implementation)
struct Foo<T, U> {
    #[pin]
    future: T,
    field: U,
}

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

// Automatically create the appropriate conditional Unpin implementation (optional).
// impl<T, U> Unpin for Foo<T, U> where T: Unpin {}

Code like this will be generated

License

Licensed under either of

at your option.

Contribution

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.

Dependencies

~797KB
~18K SLoC