I've recently come across an Apple document that shows the following property declaration for a block:
@interface XYZObject : NSObject
@property (copy) void (^blockProperty)(void);
@end
Also, this article states:
Note: You should specify copy as the property attribute, because a block needs to be copied to keep track of its captured state outside of the original scope. This isn’t something you need to worry about when using Automatic Reference Counting, as it will happen automatically, but it’s best practice for the property attribute to show the resultant behavior. For more information, see Blocks Programming Topics.
I also read the suggested Blocks Programming Topics but haven't found anything relevant there.
I'm still curious as to why defining a block property as "copy" is best practice. If you have a good answer, please try to distinguish between ARC and MRC differences if there are any.
Thank you
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