/// <summary>
/// Unwrap a stream inside a cell to give a time-varying stream implementation.
/// When the cell changes value, the output stream will fire the simultaneous firing (if one exists) from the stream which the cell held at the beginning of the transaction.
/// </summary>
/// <typeparam name="T">The type of the stream.</typeparam>
/// <param name="csa">The cell containing the stream.</param>
/// <returns>The unwrapped stream.</returns>
public static Stream <T> SwitchS <T>(this Cell <Stream <T> > csa)
{
return(Transaction.Apply(trans1 =>
{
Stream <T> @out = new Stream <T>();
IListener currentListener = null;
Action <Transaction, Stream <T> > hInitial = (trans2, sa) =>
{
currentListener?.Unlisten();
currentListener = sa.Listen(@out.Node, trans2, @out.Send, false);
};
Action <Transaction, Stream <T> > h = (trans2, sa) =>
{
trans2.Last(() =>
{
currentListener?.Unlisten();
currentListener = sa.Listen(@out.Node, trans2, @out.Send, true);
});
};
trans1.Prioritized(new Node <T>(), trans2 => hInitial(trans2, csa.SampleNoTransaction()));
IListener l1 = csa.Updates(trans1).Listen(@out.Node, trans1, h, false);
return @out.UnsafeAttachListener(l1);
}, false));
}
/// <summary>
/// Unwrap a stream inside a cell to give a time-varying stream implementation.
/// When the cell changes value, the output stream will fire the simultaneous firing (if one exists) from the stream
/// which the cell held at the beginning of the transaction.
/// </summary>
/// <typeparam name="T">The type of the stream.</typeparam>
/// <param name="csa">The cell containing the stream.</param>
/// <returns>The unwrapped stream.</returns>
public static Stream <T> SwitchS <T>(this Cell <Stream <T> > csa)
{
return(Transaction.Apply(
trans1 =>
{
Stream <T> @out = new Stream <T>(csa.KeepListenersAlive);
MutableListener currentListener = new MutableListener();
void HInitial(Transaction trans2, Stream <T> sa)
{
currentListener.Unlisten();
currentListener.SetListener(sa.Listen(@out.Node, trans2, @out.Send, false));
}
void H(Transaction trans2, Stream <T> sa)
{
trans2.Last(
() =>
{
currentListener.Unlisten();
currentListener.SetListener(sa.Listen(@out.Node, trans2, @out.Send, true));
});
}
trans1.Prioritized(new Node <T>(), trans2 => HInitial(trans2, csa.SampleNoTransaction()));
IListener l1 = csa.Updates(trans1).Listen(new Node <T>(), trans1, H, false);
return @out.UnsafeAttachListener(l1).UnsafeAttachListener(currentListener);
},
false));
}
/// <summary>
/// Unwrap a stream inside a cell to give a time-varying stream implementation.
/// </summary>
/// <typeparam name="T">The type of the stream.</typeparam>
/// <param name="csa">The cell containing the stream.</param>
/// <returns>The unwrapped stream.</returns>
public static Stream <T> SwitchS <T>(this Cell <Stream <T> > csa)
{
return(Transaction.Apply(trans1 =>
{
Stream <T> @out = new Stream <T>();
IListener currentListener = csa.SampleNoTransaction().Listen(@out.Node, trans1, @out.Send, false);
Action <Transaction, Stream <T> > h = (trans2, sa) =>
{
trans2.Last(() =>
{
using (currentListener)
{
}
currentListener = sa.Listen(@out.Node, trans2, @out.Send, true);
});
};
IListener l1 = csa.Updates(trans1).Listen(@out.Node, trans1, h, false);
return @out.UnsafeAddCleanup(l1);
}));
}