System\Linq\Enumerable.cs (6)
974return Lookup<TKey, TSource>.Create(source, keySelector, IdentityFunction<TSource>.Instance, null);
978return Lookup<TKey, TSource>.Create(source, keySelector, IdentityFunction<TSource>.Instance, comparer);
982return Lookup<TKey, TElement>.Create(source, keySelector, elementSelector, null);
986return Lookup<TKey, TElement>.Create(source, keySelector, elementSelector, comparer);
2504Lookup<TKey, TElement> lookup = Lookup<TKey, TElement>.Create<TSource>(source, keySelector, elementSelector, comparer);
2531return Lookup<TKey, TElement>.Create<TSource>(source, keySelector, elementSelector, comparer).GetEnumerator();