Hash value of NSDictionary

Question

I ran into an issue, where I got the same hash value for different dictionaries. Maybe I\'m doing something obvious wrong, but I thought, objects with different content (a.k

Answer 1

A solution based on igor-kulagin's answer which is not order dependent:

@implementation NSDictionary (Extensions)

- (NSUInteger) hash
{
    NSUInteger prime = 31;
    NSUInteger result = 1;
    for (NSObject *key in [[self allKeys] sortedArrayUsingSelector:@selector(compare:)]) {
        result = prime * result + [key hash];
        result = prime * result + [self[key] hash];
    }
    return result;
}
@end

However, there is still a possibility of collision if the dictionary contains other dictionaries as values.