System\Linq\Distinct.cs (2)
39public static IEnumerable<TSource> DistinctBy<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector) => DistinctBy(source, keySelector, null);
51/// <para>The <see cref="DistinctBy{TSource, TKey}(IEnumerable{TSource}, Func{TSource, TKey}, IEqualityComparer{TKey}?)" /> method returns an unordered sequence that contains no duplicate values. If <paramref name="comparer" /> is <see langword="null" />, the default equality comparer, <see cref="EqualityComparer{T}.Default" />, is used to compare values.</para>