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emreberge/KeyPath.h

Last active September 3, 2015 12:15
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Compiler help for keyPaths!
Raw
KeyPath.h
#define KeyPath(keyPath)\
^NSString *(void) {\
__unused __typeof__(keyPath) x;\
return [@#keyPath substringFromIndex:([@#keyPath rangeOfString:@"."].location + 1)];\
}()
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screen shot 2015-07-27 at 21 58 08

@akull
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akull commented Aug 19, 2015

I often find that you want to observe an object that is already a property of another object, and then this kind of breaks down. For example, this snippet does not work:

[self.object addObserver:self forKeyPath:KeyPath(self.object.myCoolKeyPath) options:kNilOptions context:NULL]

To support this case as well, we can add the NSBackwardsSearch option to the rangeOfString call.

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