Initial data commit

Task/Filter/Sather/filter.sa

@@ -0,0 +1,23 @@
+class MARRAY{T} < $ARR{T} is
+  include ARRAY{T};
+
+  filter_by(r:ROUT{T}:BOOL):SAME is
+    o:MARRAY{T} := #;
+    loop e ::= elt!;
+      if r.call(e) then
+        o := o.append(#MARRAY{T}(|e|));
+      end;
+    end;
+    return o;
+  end;
+
+end;
+
+class MAIN is
+  main is
+    a ::= #MARRAY{INT}(|5, 6, 7, 8, 9, 10, 11|);
+    sel ::= a.filter_by( bind(_.is_even) );
+    loop #OUT + sel.elt! + " "; end;
+    #OUT + "\n";
+  end;
+end;