static Turtle MoveTurtleCopy(Turtle t, int deltaX, int deltaY) { return t.Copy(position: t.Position.Copy(x: t.Position.X + deltaX, y: t.Position.Y + deltaY)); }
static Turtle MoveTurtle(Turtle t, int deltaX, int deltaY) { return (from x in TurtleX.ModS(x => x + deltaX) from y in TurtleY.ModS(y => y + deltaY) select Tuple.Create(x, y)).Run(t).Item1; }