public static IPosition Neighbour(this IPosition position, IDirection direction)
{
var index = position.Along(direction.Alignment) + direction.Delta.Quantity();
if (index < -1 || 1 < index)
{
return null;
}
switch (direction.Alignment)
{
case Alignment.Columns:
return new Position((Columns) index, position.Row);
case Alignment.Rows:
return new Position(position.Column, (Rows) index);
default:
throw new ArgumentException();
}
}
