Swift vs. +[NSValue valueWithNonretainedObject:]

Question

In Objective-C, I might use +[NSValue valueWithNonretainedObject:] to keep a unique ID of an object, where I don't wish to retain the object itself. Seems like that's deprecated for Swift.

How to do in Swift?

score 7 · Accepted Answer · edited Jun 27 '14 at 14:24

7

It's still there. It's just been adjusted to be one of NSValue's initializers:

let anObject = "Hello!"
let value = NSValue(nonretainedObject: anObject)

edited Jun 27 '14 at 14:24

Clay Bridges

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answered Jun 27 '14 at 14:17

Mick MacCallum

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Doh. Gotta think more Swifty. – Clay Bridges Jun 27 '14 at 14:24

score 3 · Answer 2 · answered Jun 27 '14 at 14:17

3

This works:

let foo: NSString = "hello"
let fooval: NSValue = NSValue(nonretainedObject: foo)

fooval.description // evaluates to "<5040d191 b87f0000>", address of `foo`

answered Jun 27 '14 at 14:17

hamstergene

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Swift vs. +[NSValue valueWithNonretainedObject:]

2 Answers2