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Re: dispatch queue as property
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Re: dispatch queue as property


  • Subject: Re: dispatch queue as property
  • From: Andreas Grosam <email@hidden>
  • Date: Wed, 02 Nov 2011 15:30:22 +0100

On Nov 2, 2011, at 1:33 PM, Jamie Pinkham wrote:

> Automatic property generation doesn't support the semantics you need.
>
> You are correct that you have to use the dispatch_retain() and dispatch_release() functions; you just have write your setter and getter manually, using those functions.

Sure, the property can't  be synthesized. But even when I define setter and getter in the @implementation, I can't declare the property like:

@proprty (retain) dispatch_queue_t dispatchQueue;

in order to indicate the semantics,

since the compiler (clang) will refuse it with
"error: property with 'retain (or strong)' attribute must be of object type [3]"


So, according the compiler, the property attribute "retain" does not indicate a certain (and general) semantic, but assumes a specific implementation applicable only for ObjC objects. Or, in other words, when I state "retain", then I shall use objects and if I implement setter and getter, they shall invoke retain and release.

I would understand if the compiler would only complain about the "retain" attribute if it must synthesize it for "unknown" types.

Andreas


>
> -Jamie
>
> Sent from my iPhone
>
> On Nov 2, 2011, at 7:52 AM, Andreas Grosam <email@hidden> wrote:
>
>> I want to set a dispatch queue via a property. How should I set the property's attributes when the queue is retained/released via functions dispatch_retain() and dispatch_release()?
>>
>> Currently, since using "retain" is only possible for objects, I just declare it like follows:
>>
>> @property (nonatomic) dispatch_queue_t dispatchQueue;
>>
>>
>> But here, the retain/release semantic isn't exposed. Any better ideas?
>>
>>
>>
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  • Follow-Ups:
    • Re: dispatch queue as property
      • From: Jean-Daniel Dupas <email@hidden>
    • Re: dispatch queue as property
      • From: Jamie Pinkham <email@hidden>
References: 
 >dispatch queue as property (From: Andreas Grosam <email@hidden>)
 >Re: dispatch queue as property (From: Jamie Pinkham <email@hidden>)

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