How to set CMutablePointer to false in Swift?

Question

Basically I'm using the AssetsLibrary frameworks in Swift, how could I modify the value of the stop pointer to NO/False/0 (I don't even know what value it should except) ?

self.library.enumerateGroupsWithTypes(ALAssetsGroupType(ALAssetsGroupSavedPhotos), usingBlock: {(group: ALAssetsGroup!, stop: CMutablePointer<ObjCBool>) in

},
failureBlock: {(error: NSError!) in

})

I should be able to access the value and modify it with unsafePointer but I can't seems to be able to write the closure correctly.

BTW, you set this to `true` when you want to stop, not `false`. If you want it to continue, you simply leave it alone. — Rob, Aug 01 '14 at 22:37

Jean-Philippe Pellet · Accepted Answer · 2014-06-11T14:21:45.943

17

This is the equivalent of *stop = YES;:

stop.withUnsafePointer { $0.memory = true }

To make it more succinct, you could do things like:

operator infix <- {}

@infix func <- <T>(ptr: CMutablePointer<T>, value: T) {
    ptr.withUnsafePointer { $0.memory = value }
}

and then the line above becomes simply this:

stop <- true

Not sure if that's recommended style, though...

(You can choose characters from / = - + * % < > ! & | ^ . ~ to create custom operators.)

edited Jun 11 '14 at 14:21

answered Jun 10 '14 at 14:00

Jean-Philippe Pellet

59,296
21
173
234

2

Haha, I love seeing what people come up with operator overloading...this is a great one! – Jack Jun 10 '14 at 14:16
Don't worry about the downvoter, he must be an ass. Yours is the most enlightening answer I've read about Swift since it was announced. +1 from me, anyways. – original_username Jul 10 '14 at 11:35

score 9 · Answer 2 · edited May 23 '17 at 10:30

9

As of Xcode 6 beta 4, you can now do:

stop.memory = true

Or, as holex noted, you can:

stop.initialize(true)

edited May 23 '17 at 10:30

Community

1
1

answered Aug 01 '14 at 16:03

Rob

415,655
72
787
1,044

If you want to post your own answer here, I'm happy to remove mine. I'd rather see you get the reputation points! – Rob Aug 01 '14 at 16:09
1

thank you, that is very generous from you! I'm not chasing credits, I'm glad to help only. :) just for fun, you know... :) – holex Aug 01 '14 at 16:12

score 1 · Answer 3 · answered Sep 28 '20 at 00:59

1

in Swift 5:

stop.pointee = true

answered Sep 28 '20 at 00:59

nathanwhy

5,884
1
12
13

How to set CMutablePointer to false in Swift?

3 Answers3

Linked