/// <summary>
/// Return a reference to this <see cref="CellSink{T}" /> as a <see cref="Cell{T}" />.
/// </summary>
/// <typeparam name="T">The type of the cell sink.</typeparam>
/// <param name="c">The cell sink.</param>
/// <returns>A reference to this <see cref="CellSink{T}" /> as a <see cref="Cell{T}" />.</returns>
public static Cell <T> AsCell <T>(this CellSink <T> c) => c;
public static void Send <T>(this CellSink <T> c, T a) => c.SendImpl(a);