non-primes

non-primes.oz

@@ -0,0 +1,51 @@
+% non primes
+declare
+fun {Prod X Stop}
+   if X>Stop then nil
+   else X|{Prod X+1 Stop}
+   end
+end
+
+declare
+fun {Filter Xs C}
+   case Xs of nil then nil
+   [] X|Xr then
+      if (X mod C)==0 then
+	 {Filter Xr C}
+      else
+	 X|{Filter Xr C}
+      end
+   end
+end
+
+declare
+fun {Sieve Xs}
+   case Xs of nil then nil
+   [] X|Xr then
+      X|{Sieve thread {Delay 1000} {Filter Xr X} end}
+   end
+end
+
+declare
+fun {NotPrime S1 S2}
+   case S2
+   of nil then S1
+   [] X2|X2r then
+      case S1
+      of nil then nil
+      [] X1|X1r then
+	 if X1==X2 then
+	    {NotPrime X1r X2r}
+	 else
+	    X1|{NotPrime X1r S2}
+	 end
+      end
+   end      
+end
+
+local P S NP in
+   P=thread {Prod 2 100} end
+   S=thread {Sieve P} end
+   NP=thread {NotPrime P S} end
+   {Browse NP}
+end