How to assign a value to an pointer-pointer passed in call by reference?

Posted by mystify on Stack Overflow See other posts from Stack Overflow or by mystify
Published on 2010-04-22T09:48:19Z Indexed on 2010/04/22 9:53 UTC
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objective-c

I want to achieve something similar to what these guys do here:

- (NSUInteger)countForFetchRequest:(NSFetchRequest *)request error:(NSError **)error

like you can see, you pass an NSError pointer and that nice method will assign a real NSError object to your pointer in case there is an error. So the cool thing about this is, that the method returns an NSUInteger but can ALSO return an NSError, without having to mess around with ugly and fat arrays or dictionaries.

So how could I assign an object to the passed-in error pointer?

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Developer IT

How to assign a value to an pointer-pointer passed in call by reference? - Developer IT

How to assign a value to an pointer-pointer passed in call by reference?

objective-c

Related posts about objective-c

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ObjectiveC Syntax for Specifying Protocol Name in Method Argument

ObjectiveC builtin template system ?

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