: board@block ( board block -- n row )
[ second swap rows>> nth ] keep first swap ;
-: set-block ( board block colour -- ) -rot board@block set-nth ;
+: set-block ( board block color -- ) -rot board@block set-nth ;
-: block ( board block -- colour ) board@block nth ;
+: block ( board block -- color ) board@block nth ;
: block-free? ( board block -- ? ) block not ;