public static class EnumerableExtensions
{
	public static IPartitionedEnumerable<T> Partition<T>(this IEnumerable<T> source, Func<T, bool> selector)
		=> new IPartitionedEnumerable<T>(source, selector);
}

public class IPartitionedEnumerable<T> : IEnumerable<T>
{
	private Func<T, bool> _selector;
	private IEnumerable<T> _source;

	public IEnumerable<T> TrueValues { get; private set; }
	public IEnumerable<T> FalseValues { get; private set; }

	public IPartitionedEnumerable(IEnumerable<T> source, Func<T, bool> selector)
	{
		_source = source;
		_selector = selector;

		TrueValues = source.Where(selector);
		FalseValues = source.Where(d => !selector(d));
	}

	public void Deconstruct(out IEnumerable<T> trueValues, out IEnumerable<T> falseValues)
	{
		trueValues = TrueValues;
		falseValues = FalseValues;
	}

	public IEnumerator<T> GetEnumerator() => _source.GetEnumerator();
	IEnumerator IEnumerable.GetEnumerator() => _source.GetEnumerator();
}