gf-3.3: examples/nqueens/NQueensAscii.gf
concrete NQueensAscii of NQueens = NatAscii ** open Prelude in {
lincat S, Matrix = Str ;
Vec = {s : Str; empty : Bool} ;
ListNat, Sat = {} ;
lin nqueens _ m = m ;
lin nilV _ _ = {s=""; empty=True} ;
consV _ j k _ _ v = {s=j ++ "X" ++ k ++
case v.empty of {True=>"";False=>";"} ++
v.s;
empty=False} ;
matrix _ v = v.s ;
}