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https://github.com/bbqsrc/arc-ext

Extensions for Arc<T> such as field projection.
https://github.com/bbqsrc/arc-ext

arc projection rust

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Extensions for Arc<T> such as field projection.

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# arc-ext

Extensions for `Arc` such as field projection.

## Usage

The `ArcExt` trait implementation extends `Arc` with `.project` and `.project_option` methods.

The projection enforces lifetimes, so that no reference to it can outlive the projection (and therefore is not unsound).

See the following example:

```rust
use arc_ext::ArcExt;

#[derive(Debug, PartialEq, Eq)]
struct Top {
nested: Nested,
string: String,
}

#[derive(Debug, PartialEq, Eq)]
struct Nested {
a: u32,
b: Box<[u8]>,
c: Option>,
}

fn test() {
let top = Arc::new(Top {
nested: Nested {
a: 32,
b: vec![1, 2, 3, 4].into_boxed_slice(),
c: Some(Arc::new(Top {
nested: Nested {
a: 12,
b: vec![99].into_boxed_slice(),
c: None,
},
string: "nested".to_string(),
})),
},
string: "owned str".to_string(),
});

let project = top.clone().project(|x| &x.nested.b);
assert_eq!(&[1, 2, 3, 4], &**project);
drop(project);

let project = top.clone().project_option(|x| x.nested.c.as_ref());
let opt = project.as_option().unwrap();
assert_eq!(top.nested.c.as_ref().unwrap(), opt);
}

```

## License

This project is licensed under either of

* Apache License, Version 2.0 ([LICENSE-APACHE](LICENSE-APACHE) or )
* MIT license ([LICENSE-MIT](LICENSE-MIT) or )

at your option.