public void Move(char dir)
{
switch (dir)
{
case 'U':
if (pos.y > 0)
{
pos = pos.Up();
if (Current() == null)
{
pos = pos.Down();
}
}
break;
case 'D':
if (pos.y < _nRows - 1)
{
pos = pos.Down();
if (Current() == null)
{
pos = pos.Up();
}
}
break;
case 'L':
if (pos.x > 0)
{
pos = pos.Left();
if (Current() == null)
{
pos = pos.Right();
}
}
break;
case 'R':
if (pos.x < _nCols - 1)
{
pos = pos.Right();
if (Current() == null)
{
pos = pos.Left();
}
}
break;
default:
throw new NotImplementedException();
}
}
public static Pos Next(this Movement move, Pos from)
{
switch (move)
{
case Movement.UP: return(from.Up());
case Movement.DOWN: return(from.Down());
case Movement.RIGHT: return(from.Right());
case Movement.LEFT: return(from.Left());
default: return(from);
}
}