Are predicates the most efficient way to lookup an object in NSSet?
Reading up the documentation about NSSet it says:
You can use sets as an alternative to arrays when the order of elements isn't important and performance in testing whether an object is contained in the set is a consideration.
Thats exactly what I need, as performance is very important to me.
So I have overriden the hash in the class that will eventually be populated in the NSSet.
- (NSUInteger)hash
{
return [[self recordDate] hash];
}
In other words recordDate is always unique in my case and I expect to have unique hashes here.
According to the documentation it seems the only way I could lookup an object in the NSSet/NSMutableSet would be through predicates.
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"recordDate == %@", recordDate];
NSSet *objectsWithDesiredWeek = [mySet filteredSetUsingPredicate:predicate];
I am not sure, if I am not overlooking something. Is this the most efficient way to lookup an object in the NSSet? Is there not something like Key/Value?
I guess I don't understand the question. NSSet has the built-in method containsObject. Why does that not meet your need?
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