static Dictionary <TKey, TSource> ToDictionaryAt <TEnumerable, TEnumerator, TSource, TKey, TKeySelector, TPredicate>(this TEnumerable source, TKeySelector keySelector, IEqualityComparer <TKey>?comparer, TPredicate predicate)
where TEnumerable : IValueReadOnlyCollection <TSource, TEnumerator>
where TEnumerator : struct, IEnumerator <TSource>
where TKey : notnull
where TKeySelector : struct, IFunction <TSource, TKey>
where TPredicate : struct, IFunction <TSource, int, bool>
=> source.Count is 0
// ReSharper disable once HeapView.ObjectAllocation.Evident
? new Dictionary <TKey, TSource>()
: ValueEnumerableExtensions.ToDictionaryAt <TEnumerable, TEnumerator, TSource, TKey, TKeySelector, TPredicate>(source, keySelector, comparer, predicate);
