/// <summary> /// Get one of each repeated element. /// </summary> public static IDistinctEnumerable <T> GetDistinctRepeatedElements <T>(this IEnumerable <T> enumerable, IEqualityComparer <T> equalityComparer) { return(enumerable .GetRepeatedElements(equalityComparer) .ToDistinct(equalityComparer)); // No repeats among the non-distinct elements. }