namespace Foundation
{
    [Register("NSMutableSet", SkipRegistration = true)]
    public sealed class NSMutableSet<TKey> : NSMutableSet, IEnumerable, IEnumerable<TKey>
        where TKey, class, INativeObject
    {
        public static NSMutableSet<TKey> operator -(NSMutableSet<TKey> first, NSMutableSet<TKey> second);
    }
}