# pin-project
[](https://travis-ci.org/taiki-e/pin-project)
[](https://crates.io/crates/pin-project/)
[](https://docs.rs/pin-project/)
[](https://crates.io/crates/pin-project/)
[](https://blog.rust-lang.org/2019/02/28/Rust-1.33.0.html)
An attribute that creates a projection struct covering all the fields.
[Documentation](https://docs.rs/pin-project/)
## Usage
Add this to your `Cargo.toml`:
```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.
```rust
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](doc/struct-example-1.md)
[`unsafe_project`]: https://docs.rs/pin-project/0.3/pin_project/attr.unsafe_project.html
## License
Licensed under either of
* Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or <http://www.apache.org/licenses/LICENSE-2.0>)
* MIT license ([LICENSE-MIT](LICENSE-MIT) or <http://opensource.org/licenses/MIT>)
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.