+ if (Math.abs(m.end.x-m.start.x)==2 && !this.pawnFlags[this.turn][m.start.y])
+ return; //skip forbidden 2-squares jumps
+ if (this.board[m.end.x][m.end.y] == VariantRules.EMPTY
+ && m.vanish.length==2 && this.getColor(m.start.x,m.start.y) == 'c')
+ {
+ return; //checkered pawns cannot take en-passant
+ }