#objective-c #osx #ios

objc_id

Rust smart pointers for Objective-C reference counting

4 releases

0.1.1 Jul 22, 2018
0.1.0 Mar 20, 2016
0.0.2 Sep 3, 2015
0.0.1 May 2, 2015

#5 in macOS APIs

Download history 546/week @ 2018-05-27 501/week @ 2018-06-03 582/week @ 2018-06-10 484/week @ 2018-06-17 386/week @ 2018-06-24 410/week @ 2018-07-01 475/week @ 2018-07-08 459/week @ 2018-07-15 660/week @ 2018-07-22 879/week @ 2018-07-29 1044/week @ 2018-08-05 1143/week @ 2018-08-12 931/week @ 2018-08-19

2,180 downloads per month
Used in 64 crates (11 directly)

MIT license

10KB
151 lines

Rust smart pointers for Objective-C reference counting.

To ensure that Objective-C objects are retained and released at the proper times, we can use the Id struct.

To enforce aliasing rules, an Id can be either owned or shared; if it is owned, meaning the Id is the only reference to the object, it can be mutably dereferenced. An owned Id can be downgraded to a ShareId which can be cloned to allow multiple references.

Weak references may be created using the WeakId struct.

use objc::runtime::{Class, Object};
use objc_id::{Id, WeakId};

let cls = Class::get("NSObject").unwrap();
let obj: Id<Object> = unsafe {
    Id::from_retained_ptr(msg_send![cls, new])
};
// obj will be released when it goes out of scope

// share the object so we can clone it
let obj = obj.share();
let another_ref = obj.clone();
// dropping our other reference will decrement the retain count
drop(another_ref);

let weak = WeakId::new(&obj);
assert!(weak.load().is_some());
// After the object is deallocated, our weak pointer returns none
drop(obj);
assert!(weak.load().is_none());

Dependencies

~250KB