7

I'm trying to implement a very simple strategy class in Objective-C that allows for strategies to be defined inline instead of being defined through inheritance. Currently my code looks like this:

@interface SSTaskStrategy : NSObject {
    (NSArray *)(^strategy)(void);
}

@end

I thought this would work, but I'm getting the error

Expected specifier-qualifier-list before '(' token

Any ideas how to make this work?

iand675
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2 Answers2

17

You should drop the parentheses around NSArray * in your ivar definition:

@interface SSTaskStrategy : NSObject {
    NSArray * (^strategy)(void);
}

@end

Also, I highly recommend that you use a typedef for more clarity:

typedef NSArray * (^Strategy)(void);

@interface SSTaskStrategy : NSObject {
   Strategy block;
}

@end

This allows you to reference this block with the name Strategy instead of having to use the funky syntax every single time you wish to reference it.

Jacob Relkin
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2
@interface SSTaskStrategy : NSObject {
    NSArray* (^strategy)(void);
}

You don't need to put the ( ) around the return type.

kennytm
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