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@brentsimmons
Created July 28, 2012 19:06
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Checking if an object is empty
BOOL RSIsEmpty(id obj) {
return obj == nil || obj == [NSNull null] || ([obj respondsToSelector:@selector(length)] && [(NSData *)obj length] == 0) || ([obj respondsToSelector:@selector(count)] && [obj count] == 0);
}
BOOL RSStringIsEmpty(NSString *s) {
/*22 Feb. 2011: added NSNull check. JSON parser can put a null where we expect a string, and NSNull throws an exception when checking length. Since [NSNull null] is, arguably, emptiness, it makes sense to include it.*/
return s == nil || (id)s == (id)[NSNull null] || [s length] == 0;
}
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In general I agree with you completely -- the object-oriented approach is best. But I will consider that there are occasional special cases, and I think this is one.

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