public IEnumerable <string> YieldValidMoves()
{
foreach (FigureOnSquare fs in board.YieldMyFiguresOnSquares())
{
foreach (Square to in Square.YieldBoardSquares())
{
foreach (Figure promotion in fs.figure.YieldPromotions(to))
{
FigureMoving fm = new FigureMoving(fs, to, promotion);
if (moves.CanMove(fm))
{
if (!board.IsCheckAfter(fm))
{
yield return(fm.ToString());
}
}
}
}
}
}