#owning #reference #sibling #field #siblings

ccl_owning_ref

A library for creating references that carry their owner with them

3 releases

Uses old Rust 2015

0.4.2 Jul 16, 2019
0.4.1 Jun 22, 2019
0.4.0 Jun 19, 2019

#2117 in Rust patterns

26 downloads per month

MIT license

78KB
1K SLoC

This is a fork of the original crate to enable some specific functionality. Contact me for questions or requests.

owning-ref-rs

A library for creating references that carry their owner with them.

This can sometimes be useful because Rust borrowing rules normally prevent moving a type that has been borrowed from. For example, this kind of code gets rejected:

fn return_owned_and_referenced<'a>() -> (Vec<u8>, &'a [u8]) {
    let v = vec![1, 2, 3, 4];
    let s = &v[1..3];
    (v, s)
}

This library enables this safe usage by keeping the owner and the reference bundled together in a wrapper type that ensure that lifetime constraint:

fn return_owned_and_referenced() -> OwningRef<Vec<u8>, [u8]> {
    let v = vec![1, 2, 3, 4];
    let or = OwningRef::new(v);
    let or = or.map(|v| &v[1..3]);
    or
}

Travis-CI Status

Getting Started

owning-ref-rs is available on crates.io. It is recommended to look there for the newest released version, as well as links to the newest builds of the docs.

At the point of the last update of this README, the latest published version could be used like this:

Add the following dependency to your Cargo manifest...

[dependencies]
owning_ref = "0.3"

...and see the docs for how to use it.

Example

extern crate owning_ref;
use owning_ref::BoxRef;

fn main() {
    // Create an array owned by a Box.
    let arr = Box::new([1, 2, 3, 4]) as Box<[i32]>;

    // Transfer into a BoxRef.
    let arr: BoxRef<[i32]> = BoxRef::new(arr);
    assert_eq!(&*arr, &[1, 2, 3, 4]);

    // We can slice the array without losing ownership or changing type.
    let arr: BoxRef<[i32]> = arr.map(|arr| &arr[1..3]);
    assert_eq!(&*arr, &[2, 3]);

    // Also works for Arc, Rc, String and Vec!
}

Dependencies

~0.6–0.9MB
~14K SLoC