Stashbox by Peter Csajtai

<PackageReference Include="Stashbox" Version="4.1.0-preview-677" />

.NET API 180,224 bytes

 EnumerableExtensions

static class EnumerableExtensions
public static ExpandableArray<TItem> AsExpandableArray<TItem>(this IEnumerable<TItem> enumerable)

public static Pair<bool, ParameterExpression>[] AsParameterPairs(this ParameterExpression[] source)

public static ParameterExpression[] AsParameters(this Type[] source)

public static Stack<TItem> AsStack<TItem>(this IEnumerable<TItem> enumerable)

public static TEnumerable[] CastToArray<TEnumerable>(this IEnumerable<TEnumerable> enumerable)

public static bool ContainsReference<TElement>(this TElement[] array, TElement element)

public static int GetReferenceIndex<TElement>(this TElement[] array, TElement element)

public static TResult LastElement<TResult>(this TResult[] source)

public static TResult[] SelectButLast<TSource, TResult>(this TSource[] source, Func<TSource, TResult> selector)

public static TEnumerable[] WhereOrDefault<TEnumerable>(this IEnumerable<TEnumerable> enumerable, Func<TEnumerable, bool> predicate)